Sample records for continuous process vents

  1. 40 CFR 65.62 - Process vent group determination.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., or Group 2B) for each process vent. Group 1 process vents require control, and Group 2A and 2B... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Process vent group determination. 65... (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Process Vents § 65.62 Process vent group determination. (a) Group...

  2. 40 CFR 65.62 - Process vent group determination.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 16 2012-07-01 2012-07-01 false Process vent group determination. 65... (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Process Vents § 65.62 Process vent group determination. (a) Group status. The owner or operator of a process vent shall determine the group status (i.e., Group 1, Group 2A...

  3. 40 CFR 65.62 - Process vent group determination.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 16 2014-07-01 2014-07-01 false Process vent group determination. 65... (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Process Vents § 65.62 Process vent group determination. (a) Group status. The owner or operator of a process vent shall determine the group status (i.e., Group 1, Group 2A...

  4. 40 CFR 65.62 - Process vent group determination.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 15 2011-07-01 2011-07-01 false Process vent group determination. 65... (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Process Vents § 65.62 Process vent group determination. (a) Group status. The owner or operator of a process vent shall determine the group status (i.e., Group 1, Group 2A...

  5. 40 CFR 63.2455 - What requirements must I meet for continuous process vents?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CATEGORIES National Emission Standards for Hazardous Air Pollutants: Miscellaneous Organic Chemical... any continuous process vent that is combined with Group 1 batch process vents before a control device or recovery device because the requirements of § 63.2450(c)(2)(i) apply to the combined stream. (2...

  6. 40 CFR 63.1104 - Process vents from continuous unit operations: applicability assessment procedures and methods.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... permit limit applicable to the process vent. (iv) Design analysis based on accepted chemical engineering... rates, halogenated process vent determinations, process vent TRE index values, and engineering... corrected to 2.3 percent moisture; or (2) The engineering assessment procedures in paragraph (k) of this...

  7. 40 CFR 63.1104 - Process vents from continuous unit operations: applicability assessment procedures and methods.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... permit limit applicable to the process vent. (iv) Design analysis based on accepted chemical engineering... rates, halogenated process vent determinations, process vent TRE index values, and engineering... corrected to 2.3 percent moisture; or (2) The engineering assessment procedures in paragraph (k) of this...

  8. 40 CFR 63.1104 - Process vents from continuous unit operations: applicability assessment procedures and methods.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... permit limit applicable to the process vent. (iv) Design analysis based on accepted chemical engineering... rates, halogenated process vent determinations, process vent TRE index values, and engineering... corrected to 2.3 percent moisture; or (2) The engineering assessment procedures in paragraph (k) of this...

  9. 40 CFR 63.1104 - Process vents from continuous unit operations: applicability assessment procedures and methods.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... permit limit applicable to the process vent. (iv) Design analysis based on accepted chemical engineering... rates, halogenated process vent determinations, process vent TRE index values, and engineering... corrected to 2.3 percent moisture; or (2) The engineering assessment procedures in paragraph (k) of this...

  10. 40 CFR Table 1 to Subpart Ffff of... - Emission Limits and Work Practice Standards for Continuous Process Vents

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Pollutants: Miscellaneous Organic Chemical Manufacturing Pt. 63, Subpt. FFFF, Table 1 Table 1 to Subpart FFFF... continuous process vent a. Not applicable i. Reduce emissions of total organic HAP by ≥98 percent by weight or to an outlet process concentration ≤20 ppmv as organic HAP or TOC by venting emissions through a...

  11. 40 CFR 63.1322 - Batch process vents-reference control technology.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 12 2013-07-01 2013-07-01 false Batch process vents-reference control... (CONTINUED) National Emission Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins § 63.1322 Batch process vents—reference control technology. (a) Batch process vents. The owner or...

  12. 40 CFR 63.1322 - Batch process vents-reference control technology.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 12 2012-07-01 2011-07-01 true Batch process vents-reference control technology. 63.1322 Section 63.1322 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Batch process vents—reference control technology. (a) Batch process vents. The owner or operator of a...

  13. 40 CFR 63.1322 - Batch process vents-reference control technology.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 12 2014-07-01 2014-07-01 false Batch process vents-reference control technology. 63.1322 Section 63.1322 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... § 63.1322 Batch process vents—reference control technology. (a) Batch process vents. The owner or...

  14. 40 CFR 63.1322 - Batch process vents-reference control technology.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 11 2011-07-01 2011-07-01 false Batch process vents-reference control technology. 63.1322 Section 63.1322 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Batch process vents—reference control technology. (a) Batch process vents. The owner or operator of a...

  15. 40 CFR 63.1322 - Batch process vents-reference control technology.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Batch process vents-reference control technology. 63.1322 Section 63.1322 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Batch process vents—reference control technology. (a) Batch process vents. The owner or operator of a...

  16. 40 CFR 63.7890 - What emissions limitations and work practice standards must I meet for process vents?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS... Pollutants: Site Remediation Process Vents § 63.7890 What emissions limitations and work practice standards...

  17. 40 CFR 63.7890 - What emissions limitations and work practice standards must I meet for process vents?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS... Pollutants: Site Remediation Process Vents § 63.7890 What emissions limitations and work practice standards...

  18. 40 CFR 63.7890 - What emissions limitations and work practice standards must I meet for process vents?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS... Pollutants: Site Remediation Process Vents § 63.7890 What emissions limitations and work practice standards...

  19. 40 CFR 63.7890 - What emissions limitations and work practice standards must I meet for process vents?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS... Pollutants: Site Remediation Process Vents § 63.7890 What emissions limitations and work practice standards...

  20. 40 CFR 63.1326 - Batch process vents-recordkeeping provisions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins... requirements for Group 2 batch process vents that are exempt from the batch mass input limitation provisions...

  1. 40 CFR 65.65 - Monitoring.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Monitoring. 65.65 Section 65.65 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Process Vents § 65.65 Monitoring. (a) An owner or operator of a Group 2A process vent...

  2. 40 CFR Table 1 to Subpart Ffff of... - Emission Limits and Work Practice Standards for Continuous Process Vents

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...: Miscellaneous Organic Chemical Manufacturing Pt. 63, Subpt. FFFF, Table 1 Table 1 to Subpart FFFF of Part 63... vent a. Not applicable i. Reduce emissions of total organic HAP by ≥98 percent by weight or to an outlet process concentration ≤20 ppmv as organic HAP or TOC by venting emissions through a closed-vent...

  3. 40 CFR Table 1 to Subpart Ffff of... - Emission Limits and Work Practice Standards for Continuous Process Vents

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...: Miscellaneous Organic Chemical Manufacturing Pt. 63, Subpt. FFFF, Table 1 Table 1 to Subpart FFFF of Part 63... vent a. Not applicable i. Reduce emissions of total organic HAP by ≥98 percent by weight or to an outlet process concentration ≤20 ppmv as organic HAP or TOC by venting emissions through a closed-vent...

  4. 40 CFR 63.11935 - What CEMS and CPMS requirements must I meet to demonstrate initial and continuous compliance with...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... process vents in Table 1 or 2 to this subpart. You must meet the CPMS requirements in paragraph (c) of... parameter specified in Table 5 to this subpart for each process vent control device specified in § 63.11925(b) that is used to comply with the emission limits for process vents in Table 1 or 2 to this subpart...

  5. 40 CFR 63.11935 - What CEMS and CPMS requirements must I meet to demonstrate initial and continuous compliance with...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... process vents in Table 1 or 2 to this subpart. You must meet the CPMS requirements in paragraph (c) of... parameter specified in Table 5 to this subpart for each process vent control device specified in § 63.11925(b) that is used to comply with the emission limits for process vents in Table 1 or 2 to this subpart...

  6. 40 CFR 63.11935 - What CEMS and CPMS requirements must I meet to demonstrate initial and continuous compliance with...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... process vents in Table 1 or 2 to this subpart. You must meet the CPMS requirements in paragraph (c) of... parameter specified in Table 5 to this subpart for each process vent control device specified in § 63.11925(b) that is used to comply with the emission limits for process vents in Table 1 or 2 to this subpart...

  7. 40 CFR 63.2480 - What requirements must I meet for equipment leaks?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... affected source. (5) For pumps in light liquid service in an MCPU that has no continuous process vents and.../vapor and light liquid service at an existing source, you may elect to comply with the requirements in... light liquid service in an MCPU that has no continuous process vents and is part of an existing source...

  8. 40 CFR 63.1326 - Batch process vents-recordkeeping provisions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) National Emission Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins § 63.1326 Batch process vents—recordkeeping provisions. (a) Group determination records for batch... this section for each batch process vent subject to the group determination procedures of § 63.1323...

  9. 40 CFR 63.7893 - How do I demonstrate continuous compliance with the emissions limitations and work practice...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...(b)(2), you maintain emissions of TOC (minus methane and ethane) from all affected process vents at...), you maintain that the emissions of TOC (minus methane and ethane) from all affected process vents are...

  10. Insights into shallow magmatic processes at Kīlauea Volcano, Hawaíi, from a multiyear continuous gravity time series

    NASA Astrophysics Data System (ADS)

    Poland, Michael P.; Carbone, Daniele

    2016-07-01

    Continuous gravity data collected near the summit eruptive vent at Kīlauea Volcano, Hawaíi, during 2011-2015 show a strong correlation with summit-area surface deformation and the level of the lava lake within the vent over periods of days to weeks, suggesting that changes in gravity reflect variations in volcanic activity. Joint analysis of gravity and lava level time series data indicates that over the entire time period studied, the average density of the lava within the upper tens to hundreds of meters of the summit eruptive vent remained low—approximately 1000-1500 kg/m3. The ratio of gravity change (adjusted for Earth tides and instrumental drift) to lava level change measured over 15 day windows rose gradually over the course of 2011-2015, probably reflecting either (1) a small increase in the density of lava within the eruptive vent or (2) an increase in the volume of lava within the vent due to gradual vent enlargement. Superimposed on the overall time series were transient spikes of mass change associated with inflation and deflation of Kīlauea's summit and coincident changes in lava level. The unexpectedly strong mass variations during these episodes suggest magma flux to and from the shallow magmatic system without commensurate deformation, perhaps indicating magma accumulation within, and withdrawal from, void space—a process that might not otherwise be apparent from lava level and deformation data alone. Continuous gravity data thus provide unique insights into magmatic processes, arguing for continued application of the method at other frequently active volcanoes.

  11. 40 CFR 63.7892 - What are my inspection and monitoring requirements for process vents?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 14 2014-07-01 2014-07-01 false What are my inspection and monitoring requirements for process vents? 63.7892 Section 63.7892 Protection of Environment ENVIRONMENTAL PROTECTION... SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Site Remediation...

  12. 40 CFR 63.7892 - What are my inspection and monitoring requirements for process vents?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 13 2011-07-01 2011-07-01 false What are my inspection and monitoring requirements for process vents? 63.7892 Section 63.7892 Protection of Environment ENVIRONMENTAL PROTECTION... SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Site Remediation...

  13. 40 CFR 63.7892 - What are my inspection and monitoring requirements for process vents?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 14 2012-07-01 2011-07-01 true What are my inspection and monitoring requirements for process vents? 63.7892 Section 63.7892 Protection of Environment ENVIRONMENTAL PROTECTION... SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Site Remediation...

  14. 40 CFR 63.7892 - What are my inspection and monitoring requirements for process vents?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 13 2010-07-01 2010-07-01 false What are my inspection and monitoring requirements for process vents? 63.7892 Section 63.7892 Protection of Environment ENVIRONMENTAL PROTECTION... SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Site Remediation...

  15. 40 CFR 63.7937 - How do I demonstrate initial compliance with the general standards?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... with the general standards? 63.7937 Section 63.7937 Protection of Environment ENVIRONMENTAL PROTECTION... SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Site Remediation... remediation material treated or managed by the process vented through the affected process vents has an...

  16. 40 CFR 63.7892 - What are my inspection and monitoring requirements for process vents?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 14 2013-07-01 2013-07-01 false What are my inspection and monitoring requirements for process vents? 63.7892 Section 63.7892 Protection of Environment ENVIRONMENTAL PROTECTION... SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Site Remediation...

  17. Insights into shallow magmatic processes at Kīlauea Volcano, Hawaiʻi, from a multiyear continuous gravity time series

    USGS Publications Warehouse

    Poland, Michael P.; Carbone, Daniele

    2016-01-01

    Continuous gravity data collected near the summit eruptive vent at Kīlauea Volcano, Hawaiʻi, during 2011–2015 show a strong correlation with summit-area surface deformation and the level of the lava lake within the vent over periods of days to weeks, suggesting that changes in gravity reflect variations in volcanic activity. Joint analysis of gravity and lava level time series data indicates that over the entire time period studied, the average density of the lava within the upper tens to hundreds of meters of the summit eruptive vent remained low—approximately 1000–1500 kg/m3. The ratio of gravity change (adjusted for Earth tides and instrumental drift) to lava level change measured over 15 day windows rose gradually over the course of 2011–2015, probably reflecting either (1) a small increase in the density of lava within the eruptive vent or (2) an increase in the volume of lava within the vent due to gradual vent enlargement. Superimposed on the overall time series were transient spikes of mass change associated with inflation and deflation of Kīlauea's summit and coincident changes in lava level. The unexpectedly strong mass variations during these episodes suggest magma flux to and from the shallow magmatic system without commensurate deformation, perhaps indicating magma accumulation within, and withdrawal from, void space—a process that might not otherwise be apparent from lava level and deformation data alone. Continuous gravity data thus provide unique insights into magmatic processes, arguing for continued application of the method at other frequently active volcanoes.

  18. 40 CFR 63.2450 - What are my general requirements for complying with this subpart?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... values are available for at least two of the 15-minute periods during an hour when calibration, quality... during periods of startup, shutdown, and malfunction (SSM), and you must meet the requirements specified...., continuous process vents, batch process vents, storage tanks, transfer operations, and waste management units...

  19. 40 CFR 63.2450 - What are my general requirements for complying with this subpart?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... values are available for at least two of the 15-minute periods during an hour when calibration, quality..., except during periods of startup, shutdown, and malfunction (SSM), and you must meet the requirements...., continuous process vents, batch process vents, storage tanks, transfer operations, and waste management units...

  20. 40 CFR 63.11940 - What continuous monitoring requirements must I meet for control devices required to install CPMS...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... consistent with the manufacturer's recommendations within 15 days or by the next time any process vent stream... the manufacturer's recommendations within 15 days or by the next time any process vent stream is...) Determine gas stream flow using the design blower capacity, with appropriate adjustments for pressure drop...

  1. 40 CFR 63.107 - Identification of process vents subject to this subpart.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... process vents associated with an air oxidation reactor, distillation unit, or reactor that is in a source.... (b) Some, or all, of the gas stream originates as a continuous flow from an air oxidation reactor... specified in paragraphs (c)(1) through (3) of this section. (1) Is directly from an air oxidation reactor...

  2. 40 CFR 65.115 - Standards: Closed vent systems and control devices; or emissions routed to a fuel gas system or...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Standards: Closed vent systems and control devices; or emissions routed to a fuel gas system or process. 65.115 Section 65.115 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Equipment Leaks § 65.115 Standards:...

  3. 40 CFR 63.1332 - Emissions averaging provisions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... other controls for a Group 1 storage vessel, batch process vent, aggregate batch vent stream, continuous... in control after November 15, 1990. (2) Group 1 emission points, identified in paragraph (c)(3) of... applicable reference control technology or standard and the emissions allowed for the Group 1 emission point...

  4. 40 CFR 63.1332 - Emissions averaging provisions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... other controls for a Group 1 storage vessel, batch process vent, aggregate batch vent stream, continuous... in control after November 15, 1990. (2) Group 1 emission points, identified in paragraph (c)(3) of... reference control technology or standard and the emissions allowed for the Group 1 emission point. Said...

  5. 40 CFR 65.118 - Alternative means of emission limitation: Enclosed-vented process units.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Equipment Leaks § 65.118... control device. Process units that are enclosed in such a manner that all emissions from equipment leaks...

  6. 40 CFR 65.150 - Absorbers used as control devices.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... control device on a Group 1 process vent or a high-throughput transfer rack with an absorber used as a... 40 Protection of Environment 16 2014-07-01 2014-07-01 false Absorbers used as control devices. 65... (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Closed Vent Systems, Control Devices, and Routing to a Fuel Gas...

  7. 40 CFR 65.150 - Absorbers used as control devices.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... control device on a Group 1 process vent or a high-throughput transfer rack with an absorber used as a... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Absorbers used as control devices. 65... (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Closed Vent Systems, Control Devices, and Routing to a Fuel Gas...

  8. 40 CFR 65.150 - Absorbers used as control devices.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... control device on a Group 1 process vent or a high-throughput transfer rack with an absorber used as a... 40 Protection of Environment 15 2011-07-01 2011-07-01 false Absorbers used as control devices. 65... (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Closed Vent Systems, Control Devices, and Routing to a Fuel Gas...

  9. 40 CFR 65.152 - Carbon adsorbers used as control devices.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... control device. If an owner or operator elects to replace a control device on a Group 1 process vent or... 40 Protection of Environment 15 2011-07-01 2011-07-01 false Carbon adsorbers used as control... PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Closed Vent Systems, Control Devices, and Routing to a...

  10. 40 CFR 63.7893 - How do I demonstrate continuous compliance with the emissions limitations and work practice...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ....7893 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED... Emission Standards for Hazardous Air Pollutants: Site Remediation Process Vents § 63.7893 How do I...

  11. 40 CFR 63.7893 - How do I demonstrate continuous compliance with the emissions limitations and work practice...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ....7893 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED... Emission Standards for Hazardous Air Pollutants: Site Remediation Process Vents § 63.7893 How do I...

  12. 40 CFR 63.7893 - How do I demonstrate continuous compliance with the emissions limitations and work practice...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ....7893 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED... Emission Standards for Hazardous Air Pollutants: Site Remediation Process Vents § 63.7893 How do I...

  13. 40 CFR 63.7893 - How do I demonstrate continuous compliance with the emissions limitations and work practice...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ....7893 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED... Emission Standards for Hazardous Air Pollutants: Site Remediation Process Vents § 63.7893 How do I...

  14. 40 CFR 63.690 - Standards: Process vents.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Section 63.690 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants from Off-Site Waste and Recovery Operations § 63...

  15. 40 CFR 65.164 - Performance test and flare compliance determination notifications and reports.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Closed Vent Systems, Control Devices, and Routing to a Fuel Gas System or a Process § 65.164 Performance test and flare... complete test report shall include a brief process description, sampling site description, description of...

  16. 40 CFR 63.7891 - How do I demonstrate initial compliance with the emissions limitations and work practice...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL... Standards for Hazardous Air Pollutants: Site Remediation Process Vents § 63.7891 How do I demonstrate...

  17. 40 CFR 63.7891 - How do I demonstrate initial compliance with the emissions limitations and work practice...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ....7891 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED... Emission Standards for Hazardous Air Pollutants: Site Remediation Process Vents § 63.7891 How do I...

  18. 40 CFR 63.7891 - How do I demonstrate initial compliance with the emissions limitations and work practice...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ....7891 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED... Emission Standards for Hazardous Air Pollutants: Site Remediation Process Vents § 63.7891 How do I...

  19. 40 CFR 63.7891 - How do I demonstrate initial compliance with the emissions limitations and work practice...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ....7891 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED... Emission Standards for Hazardous Air Pollutants: Site Remediation Process Vents § 63.7891 How do I...

  20. 40 CFR 65.146 - Nonflare control devices used for equipment leaks only.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Closed Vent Systems, Control Devices, and Routing to a Fuel Gas System or a Process § 65.146 Nonflare control devices used for equipment leaks only...

  1. Performance analysis of no-vent fill process for liquid hydrogen tank in terrestrial and on-orbit environments

    NASA Astrophysics Data System (ADS)

    Wang, Lei; Li, Yanzhong; Zhang, Feini; Ma, Yuan

    2015-12-01

    Two finite difference computer models, aiming at the process predictions of no-vent fill in normal gravity and microgravity environments respectively, are developed to investigate the filling performance in a liquid hydrogen (LH2) tank. In the normal gravity case model, the tank/fluid system is divided into five control volume including ullage, bulk liquid, gas-liquid interface, ullage-adjacent wall, and liquid-adjacent wall. In the microgravity case model, vapor-liquid thermal equilibrium state is maintained throughout the process, and only two nodes representing fluid and wall regions are applied. To capture the liquid-wall heat transfer accurately, a series of heat transfer mechanisms are considered and modeled successively, including film boiling, transition boiling, nucleate boiling and liquid natural convection. The two models are validated by comparing their prediction with experimental data, which shows good agreement. Then the two models are used to investigate the performance of no-vent fill in different conditions and several conclusions are obtained. It shows that in the normal gravity environment the no-vent fill experiences a continuous pressure rise during the whole process and the maximum pressure occurs at the end of the operation, while the maximum pressure of the microgravity case occurs at the beginning stage of the process. Moreover, it seems that increasing inlet mass flux has an apparent influence on the pressure evolution of no-vent fill process in normal gravity but a little influence in microgravity. The larger initial wall temperature brings about more significant liquid evaporation during the filling operation, and then causes higher pressure evolution, no matter the filling process occurs under normal gravity or microgravity conditions. Reducing inlet liquid temperature can improve the filling performance in normal gravity, but cannot significantly reduce the maximum pressure in microgravity. The presented work benefits the understanding of the no-vent fill performance and may guide the design of on-orbit no-vent fill system.

  2. The History of Venting (part I)

    NASA Technical Reports Server (NTRS)

    Leiter, Stephen C.

    2017-01-01

    Venting techniques and design are an important implementation strategy for observatory and payload contamination control, and yet venting analysis has seen a topsey turvey history, at lease from the perspective of the simple Layman trying to design a black box. Additionally, designing the vent has competing controls from Safety and EMIEMC. In the days of Shuttle, Safety placed liens against the vents of blankets, boxes, and large structural items principally to protect cargo bay vents but also from a flammability perspective. What continues to elude the Designer Community is a stable, simple way of designing vents for black boxes that satisfies everybody. But we continue to try.

  3. 40 CFR 63.133 - Process wastewater provisions-wastewater tanks.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 10 2014-07-01 2014-07-01 false Process wastewater provisions-wastewater tanks. 63.133 Section 63.133 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Chemical Manufacturing Industry for Process Vents, Storage Vessels, Transfer Operations, and Wastewater...

  4. 40 CFR 63.133 - Process wastewater provisions-wastewater tanks.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 10 2012-07-01 2012-07-01 false Process wastewater provisions-wastewater tanks. 63.133 Section 63.133 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Chemical Manufacturing Industry for Process Vents, Storage Vessels, Transfer Operations, and Wastewater...

  5. 40 CFR 63.133 - Process wastewater provisions-wastewater tanks.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 9 2011-07-01 2011-07-01 false Process wastewater provisions-wastewater tanks. 63.133 Section 63.133 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Chemical Manufacturing Industry for Process Vents, Storage Vessels, Transfer Operations, and Wastewater...

  6. 40 CFR 63.133 - Process wastewater provisions-wastewater tanks.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 10 2013-07-01 2013-07-01 false Process wastewater provisions-wastewater tanks. 63.133 Section 63.133 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Chemical Manufacturing Industry for Process Vents, Storage Vessels, Transfer Operations, and Wastewater...

  7. Using Volcanic Lightning Measurements to Discern Variations in Explosive Volcanic Activity

    NASA Astrophysics Data System (ADS)

    Behnke, S. A.; Thomas, R. J.; McNutt, S. R.; Edens, H. E.; Krehbiel, P. R.; Rison, W.

    2013-12-01

    VHF observations of volcanic lightning have been made during the recent eruptions of Augustine Volcano (2006, Alaska, USA), Redoubt Volcano (2009, Alaska, USA), and Eyjafjallajökull (2010, Iceland). These show that electrical activity occurs both on small scales at the vent of the volcano, concurrent with an eruptive event and on large scales throughout the eruption column during and subsequent to an eruptive event. The small-scale discharges at the vent of the volcano are often referred to as 'vent discharges' and are on the order of 10-100 meters in length and occur at rates on the order of 1000 per second. The high rate of vent discharges produces a distinct VHF signature that is sometimes referred to as 'continuous RF' radiation. VHF radiation from vent discharges has been observed at sensors placed as far as 100 km from the volcano. VHF and infrasound measurements have shown that vent discharges occur simultaneously with the onset of eruption, making their detection an unambiguous indicator of explosive volcanic activity. The fact that vent discharges are observed concurrent with explosive volcanic activity indicates that volcanic ejecta are charged upon eruption. VHF observations have shown that the intensity of vent discharges varies between eruptive events, suggesting that fluctuations in eruptive processes affect the electrification processes giving rise to vent discharges. These fluctuations may be variations in eruptive vigor or variations in the type of eruption; however, the data obtained so far do not show a clear relationship between eruption parameters and the intensity or occurrence of vent discharges. Further study is needed to clarify the link between vent discharges and eruptive behavior, such as more detailed lightning observations concurrent with tephra measurements and other measures of eruptive strength. Observations of vent discharges, and volcanic lightning observations in general, are a valuable tool for volcano monitoring, providing a method for rapid detection of volcanic activity in real-time.

  8. 40 CFR 63.1562 - What parts of my plant are covered by this subpart?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... regeneration of the catalyst used in the unit (i.e., the catalyst regeneration flue gas vent). (2) The process...-regenerative, cyclic, or continuous processes) that are associated with regeneration of the catalyst used in...

  9. 40 CFR 63.1562 - What parts of my plant are covered by this subpart?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... regeneration of the catalyst used in the unit (i.e., the catalyst regeneration flue gas vent). (2) The process...-regenerative, cyclic, or continuous processes) that are associated with regeneration of the catalyst used in...

  10. 40 CFR 63.1562 - What parts of my plant are covered by this subpart?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... regeneration of the catalyst used in the unit (i.e., the catalyst regeneration flue gas vent). (2) The process...-regenerative, cyclic, or continuous processes) that are associated with regeneration of the catalyst used in...

  11. 40 CFR 63.1562 - What parts of my plant are covered by this subpart?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... regeneration of the catalyst used in the unit (i.e., the catalyst regeneration flue gas vent). (2) The process...-regenerative, cyclic, or continuous processes) that are associated with regeneration of the catalyst used in...

  12. 40 CFR 63.1562 - What parts of my plant are covered by this subpart?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... regeneration of the catalyst used in the unit (i.e., the catalyst regeneration flue gas vent). (2) The process...-regenerative, cyclic, or continuous processes) that are associated with regeneration of the catalyst used in...

  13. 40 CFR 65.141 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Definitions. 65.141 Section 65.141 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Closed Vent Systems, Control Devices, and Routing to a Fuel Gas System or a Process § 65...

  14. 40 CFR 63.1405 - Continuous process vent provisions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES National Emission... affected source with a Total Resource Effectiveness (TRE) index value, as determined following the... there are conflicts between the due dates for reports presented in 40 CFR part 63, subpart SS and this...

  15. 40 CFR 63.643 - Miscellaneous process vent provisions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants From Petroleum Refineries § 63.643... section. (1) Reduce emissions of organic HAP's using a flare that meets the requirements of § 63.11(b) of...

  16. 40 CFR 63.1429 - Process vent monitoring requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... thermocouple, ultra-violet beam sensor, or infrared sensor) capable of continuously detecting the presence of a... used, a temperature monitoring device equipped with a continuous recorder is required. (i) Where an incinerator other than a catalytic incinerator is used, a temperature monitoring device shall be installed in...

  17. 40 CFR 63.1429 - Process vent monitoring requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... thermocouple, ultra-violet beam sensor, or infrared sensor) capable of continuously detecting the presence of a... used, a temperature monitoring device equipped with a continuous recorder is required. (i) Where an incinerator other than a catalytic incinerator is used, a temperature monitoring device shall be installed in...

  18. 40 CFR 63.1324 - Batch process vents-monitoring equipment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... beam sensor, or infrared sensor) capable of continuously detecting the presence of a pilot flame is...) Where an incinerator is used, a temperature monitoring device equipped with a continuous recorder is required. (i) Where an incinerator other than a catalytic incinerator is used, the temperature monitoring...

  19. 40 CFR 63.1324 - Batch process vents-monitoring equipment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... beam sensor, or infrared sensor) capable of continuously detecting the presence of a pilot flame is...) Where an incinerator is used, a temperature monitoring device equipped with a continuous recorder is required. (i) Where an incinerator other than a catalytic incinerator is used, the temperature monitoring...

  20. 40 CFR 63.1429 - Process vent monitoring requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... thermocouple, ultra-violet beam sensor, or infrared sensor) capable of continuously detecting the presence of a... used, a temperature monitoring device equipped with a continuous recorder is required. (i) Where an incinerator other than a catalytic incinerator is used, a temperature monitoring device shall be installed in...

  1. 40 CFR 63.11925 - What are my initial and continuous compliance requirements for process vents?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... accepted chemical engineering principles, measurable process parameters, or physical or chemical laws or... scale. (iv) Engineering assessment including, but not limited to, the following: (A) Previous test..., and procedures used in the engineering assessment shall be documented. (3) For miscellaneous process...

  2. 40 CFR 63.11925 - What are my initial and continuous compliance requirements for process vents?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... accepted chemical engineering principles, measurable process parameters, or physical or chemical laws or... scale. (iv) Engineering assessment including, but not limited to, the following: (A) Previous test..., and procedures used in the engineering assessment shall be documented. (3) For miscellaneous process...

  3. 40 CFR 63.11925 - What are my initial and continuous compliance requirements for process vents?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... accepted chemical engineering principles, measurable process parameters, or physical or chemical laws or... scale. (iv) Engineering assessment including, but not limited to, the following: (A) Previous test..., and procedures used in the engineering assessment shall be documented. (3) For miscellaneous process...

  4. 40 CFR Table 8 to Subpart Sssss of... - Continuous Compliance with Operating Limits

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... recent performance test; andii. Conducting annually an inspection of all duct work, vents, and capture... process operating parameters within the limits established during the most recent performance test i... processing rate at or below the maximum organic HAP processing rate established during the most recent...

  5. 40 CFR Table 8 to Subpart Sssss of... - Continuous Compliance with Operating Limits

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... recent performance test; andii. Conducting annually an inspection of all duct work, vents, and capture... process operating parameters within the limits established during the most recent performance test i... processing rate at or below the maximum organic HAP processing rate established during the most recent...

  6. 40 CFR Table 8 to Subpart Sssss of... - Continuous Compliance with Operating Limits

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... recent performance test; andii. Conducting annually an inspection of all duct work, vents, and capture... process operating parameters within the limits established during the most recent performance test i... processing rate at or below the maximum organic HAP processing rate established during the most recent...

  7. 40 CFR 65.156 - General monitoring requirements for control and recovery devices.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Closed Vent Systems, Control Devices, and Routing to a Fuel Gas System or a Process § 65.156 General monitoring requirements for... systems. (1) All monitoring equipment shall be installed, calibrated, maintained, and operated according...

  8. 40 CFR 63.7938 - How do I demonstrate continuous compliance with the general standards?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... compliance with the general standards? 63.7938 Section 63.7938 Protection of Environment ENVIRONMENTAL... Remediation General Compliance Requirements § 63.7938 How do I demonstrate continuous compliance with the....7893. (2) If the remediation material treated or managed by the process vented through the affected...

  9. 40 CFR 63.7938 - How do I demonstrate continuous compliance with the general standards?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... compliance with the general standards? 63.7938 Section 63.7938 Protection of Environment ENVIRONMENTAL... Remediation General Compliance Requirements § 63.7938 How do I demonstrate continuous compliance with the....7893. (2) If the remediation material treated or managed by the process vented through the affected...

  10. 40 CFR 63.7938 - How do I demonstrate continuous compliance with the general standards?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... compliance with the general standards? 63.7938 Section 63.7938 Protection of Environment ENVIRONMENTAL... Remediation General Compliance Requirements § 63.7938 How do I demonstrate continuous compliance with the....7893. (2) If the remediation material treated or managed by the process vented through the affected...

  11. 40 CFR 63.7938 - How do I demonstrate continuous compliance with the general standards?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... compliance with the general standards? 63.7938 Section 63.7938 Protection of Environment ENVIRONMENTAL... Remediation General Compliance Requirements § 63.7938 How do I demonstrate continuous compliance with the....7893. (2) If the remediation material treated or managed by the process vented through the affected...

  12. 40 CFR 65.6 - Startup, shutdown, and malfunction plan and procedures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 15 2011-07-01 2011-07-01 false Startup, shutdown, and malfunction... (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE General Provisions § 65.6 Startup... Group 2A or Group 2B process vents. (b) Startup, shutdown, and malfunction plan—(1) Description and...

  13. 40 CFR 65.6 - Startup, shutdown, and malfunction plan and procedures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Startup, shutdown, and malfunction... (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE General Provisions § 65.6 Startup... Group 2A or Group 2B process vents. (b) Startup, shutdown, and malfunction plan—(1) Description and...

  14. 40 CFR 65.6 - Startup, shutdown, and malfunction plan and procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 16 2014-07-01 2014-07-01 false Startup, shutdown, and malfunction... (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE General Provisions § 65.6 Startup... Group 2A or Group 2B process vents. (b) Startup, shutdown, and malfunction plan—(1) Description and...

  15. 40 CFR 65.6 - Startup, shutdown, and malfunction plan and procedures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 16 2012-07-01 2012-07-01 false Startup, shutdown, and malfunction... (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE General Provisions § 65.6 Startup... Group 2A or Group 2B process vents. (b) Startup, shutdown, and malfunction plan—(1) Description and...

  16. 40 CFR 65.6 - Startup, shutdown, and malfunction plan and procedures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 16 2013-07-01 2013-07-01 false Startup, shutdown, and malfunction... (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE General Provisions § 65.6 Startup... Group 2A or Group 2B process vents. (b) Startup, shutdown, and malfunction plan—(1) Description and...

  17. 40 CFR 63.11502 - What definitions apply to this subpart?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...: process knowledge, an engineering assessment, or test data. Byproduct means a chemical (liquid, gas, or... limit applicable to the process vent. (4) Design analysis based on accepted chemical engineering... (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources...

  18. 40 CFR 63.1412 - Continuous process vent applicability assessment procedures and methods.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... engineering principles, measurable process parameters, or physical or chemical laws or properties. Examples of... values, and engineering assessment control applicability assessment requirements are to be determined... by using the engineering assessment procedures in paragraph (k) of this section. (f) Volumetric flow...

  19. 40 CFR 63.11502 - What definitions apply to this subpart?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...: process knowledge, an engineering assessment, or test data. Byproduct means a chemical (liquid, gas, or... limit applicable to the process vent. (4) Design analysis based on accepted chemical engineering... (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources...

  20. 40 CFR 63.1412 - Continuous process vent applicability assessment procedures and methods.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... engineering principles, measurable process parameters, or physical or chemical laws or properties. Examples of... values, and engineering assessment control applicability assessment requirements are to be determined... by using the engineering assessment procedures in paragraph (k) of this section. (f) Volumetric flow...

  1. 40 CFR 63.1412 - Continuous process vent applicability assessment procedures and methods.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... engineering principles, measurable process parameters, or physical or chemical laws or properties. Examples of... values, and engineering assessment control applicability assessment requirements are to be determined... by using the engineering assessment procedures in paragraph (k) of this section. (f) Volumetric flow...

  2. 40 CFR 63.1412 - Continuous process vent applicability assessment procedures and methods.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... engineering principles, measurable process parameters, or physical or chemical laws or properties. Examples of... values, and engineering assessment control applicability assessment requirements are to be determined... by using the engineering assessment procedures in paragraph (k) of this section. (f) Volumetric flow...

  3. 40 CFR 63.1412 - Continuous process vent applicability assessment procedures and methods.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... engineering principles, measurable process parameters, or physical or chemical laws or properties. Examples of... values, and engineering assessment control applicability assessment requirements are to be determined... by using the engineering assessment procedures in paragraph (k) of this section. (f) Volumetric flow...

  4. 46 CFR 153.351 - Location of 4m vent discharges.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Location of 4m vent discharges. 153.351 Section 153.351 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS... Venting Systems § 153.351 Location of 4m vent discharges. Except as prescribed in § 153.353, a 4m venting...

  5. 40 CFR 63.485 - Continuous front-end process vent provisions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... has no stripper(s)). The limitation shall be calculated and submitted in accordance with paragraph (q... elastomer product leaving the stripper in 2010, Mg/yr 1.74 = variability factor, unitless (B) For ethylene...

  6. 40 CFR 63.485 - Continuous front-end process vent provisions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... has no stripper(s)). The limitation shall be calculated and submitted in accordance with paragraph (q... elastomer product leaving the stripper in 2010, Mg/yr 1.74 = variability factor, unitless (B) For ethylene...

  7. 40 CFR Table 35 to Subpart G of... - Control Requirements for Items of Equipment That Meet the Criteria of § 63.149 of Subpart G

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards for Organic Hazardous Air Pollutants From the Synthetic Organic Chemical Manufacturing Industry for Process Vents, Storage...

  8. Temporal change in megafauna at the Rose Garden hydrothermal vent (Galapagos Rift; eastern tropical Pacific)

    NASA Astrophysics Data System (ADS)

    Hessler, Robert R.; Smithey, William M.; Boudrias, Michel A.; Keller, Clifford H.; Lutz, Richard A.; Childress, James J.

    1988-10-01

    Hydrothermal vent communities must undergo substantial temporal change because of their dynamic physical milieu. This was verified in March 1985, when the Rose Garden hydrothermal vent on the Galapagos Rift was revisited after 5 1/4 years' absence. Comparison of photographs from the two visits revealed considerable faunal change. Among the hosts to chemoautotrophic bacteria, vestimentiferans were reduced from dominance to very low numbers. The mytilid was now extremely abundant and dominated vent openings. Vesicomyids also were more abundant. In general, vent-field suspension feeders had declined; anemones were distinctly less abundant, and siphonophores and enteropneusts were virtually absent. The decline of serpulids was likely, but less obvious. Of the mobile scavengers and carnivores, both galatheids and whelks were distincly more common. These community changes appear to result from both continuing recruitment and changes in the physical milieu. While the growth of some populations could have resulted from expanding opportunities, the population of at least one, the vesicomyid, had not achieved carrying capacity in 1979, and this could have pertained to others as well. The decrease of vestimentiferans may have been caused by declining vent-water flux, a process that would favor mytilids, or more complete vent-water filtration by the mytilids themselves. The same factors also could explain the reduction of vent-field filter feeders. These observations suggest that early stages in the cycle of Galapagos-type vent communities are likely to be dominated by vestimentiferans, but that bivalves will replace them with time.

  9. 33 CFR 159.61 - Vents.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Vents. 159.61 Section 159.61 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.61 Vents. Vents must be designed and constructed...

  10. 46 CFR 153.352 - B/3 and 4 m venting system outlets.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false B/3 and 4 m venting system outlets. 153.352 Section 153.352 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES... Cargo Venting Systems § 153.352 B/3 and 4 m venting system outlets. A B/3 or 4 m venting system outlet...

  11. 46 CFR 153.352 - B/3 and 4 m venting system outlets.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false B/3 and 4 m venting system outlets. 153.352 Section 153.352 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES... Cargo Venting Systems § 153.352 B/3 and 4 m venting system outlets. A B/3 or 4 m venting system outlet...

  12. 40 CFR 63.7938 - How do I demonstrate continuous compliance with the general standards?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Remediation General Compliance Requirements § 63.7938 How do I demonstrate continuous compliance with the....7893. (2) If the remediation material treated or managed by the process vented through the affected... required in § 63.7885(c)(2) to show that the total VOHAP concentration of the remediation material remains...

  13. Repeat terrestrial lidar mapping of the new volcanic vent at Holuhraun, Iceland

    NASA Astrophysics Data System (ADS)

    Richardson, J. A.; Whelley, P.; Sutton, S.; Needham, D. H.; Byrne, S.; Hamilton, C.

    2016-12-01

    The locations and morphologies of volcanic vents are essential observations that inform models of volcanic processes on Earth and other planets. Post-eruption morphologic changes at vents are important to characterize in order to more confidently use data gathered from mapping volcanic terrains. We present two terrestrial lidar surveys of the recently formed volcanic vent that fed the Holuhraun lava flow in the Northeastern Region of Iceland. While many studies have measured erosion rate at older volcanic vents, these surveys were performed 6 and 18 months after the end of the eruption and present an opportunity to measure morphologic changes at a brand-new vent. The Holuhraun eruption began in August 2014 by effusing lava through a fissure and continued until February 2015, emplacing approximately 1.4 km³ of lava over nearly 85 km². During the eruption the predominant activity at the northern end of the fissure produced a large (50 m high, 500 m long) cinder-canyon with scoria covered flanks. Lava ponded within this vent and drained to form a primary channel to the northeast. As lava drained through the channel, high stands of lava were preserved as "bathtub rings" on the walls of the vent. Following the cessation of activity at Holuhraun, two lidar surveys were carried out inside the vent, in August 2015 and August 2016. A Riegl VZ-400 scanner was used to collect the point cloud data, which give a precise 3D model of the vent with relative accuracy of 15 cm between scan positions. Differences between the two 3D point clouds are used to distinguish between flow emplacement and post-flow modifications to the surface, and to quantify the surface erosion rate experienced by the young vent. Near-infrared (1550 nm wavelength) reflectance values can also be correlated to lava textures and materials within the vent, providing additional information about how the vent was built syn-eruption and how it degrades post-eruption.

  14. 40 CFR 63.1406 - Reactor batch process vent provisions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 11 2011-07-01 2011-07-01 false Reactor batch process vent provisions... § 63.1406 Reactor batch process vent provisions. (a) Emission standards. Owners or operators of reactor... reactor batch process vent located at a new affected source shall control organic HAP emissions by...

  15. 40 CFR 63.1406 - Reactor batch process vent provisions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Reactor batch process vent provisions... § 63.1406 Reactor batch process vent provisions. (a) Emission standards. Owners or operators of reactor... reactor batch process vent located at a new affected source shall control organic HAP emissions by...

  16. 40 CFR 63.115 - Process vent provisions-methods and procedures for process vent group determination.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... accepted chemical engineering principles, measurable process parameters, or physical or chemical laws or... From the Synthetic Organic Chemical Manufacturing Industry for Process Vents, Storage Vessels, Transfer... (d)(3) of this section. (1) Engineering assessment may be used to determine vent stream flow rate...

  17. 40 CFR 63.115 - Process vent provisions-methods and procedures for process vent group determination.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... accepted chemical engineering principles, measurable process parameters, or physical or chemical laws or... From the Synthetic Organic Chemical Manufacturing Industry for Process Vents, Storage Vessels, Transfer... (d)(3) of this section. (1) Engineering assessment may be used to determine vent stream flow rate...

  18. 40 CFR 63.115 - Process vent provisions-methods and procedures for process vent group determination.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... accepted chemical engineering principles, measurable process parameters, or physical or chemical laws or... From the Synthetic Organic Chemical Manufacturing Industry for Process Vents, Storage Vessels, Transfer... (d)(3) of this section. (1) Engineering assessment may be used to determine vent stream flow rate...

  19. 40 CFR 63.115 - Process vent provisions-methods and procedures for process vent group determination.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... accepted chemical engineering principles, measurable process parameters, or physical or chemical laws or... From the Synthetic Organic Chemical Manufacturing Industry for Process Vents, Storage Vessels, Transfer... (d)(3) of this section. (1) Engineering assessment may be used to determine vent stream flow rate...

  20. 40 CFR 63.1429 - Process vent monitoring requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... the presence of a pilot flame. (3) Where a boiler or process heater of less than 44 megawatts design... series are used, a scrubbing liquid flow rate meter, or a pressure monitoring device, equipped with a continuous recorder, is required for each absorber in the series. An owner or operator may submit a request...

  1. 40 CFR 63.1429 - Process vent monitoring requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... the presence of a pilot flame. (3) Where a boiler or process heater of less than 44 megawatts design... series are used, a scrubbing liquid flow rate meter, or a pressure monitoring device, equipped with a continuous recorder, is required for each absorber in the series. An owner or operator may submit a request...

  2. 40 CFR 63.1407 - Non-reactor batch process vent provisions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Non-reactor batch process vent... § 63.1407 Non-reactor batch process vent provisions. (a) Emission standards. (1) Owners or operators of non-reactor batch process vents located at new or existing affected sources with 0.25 tons per year (0...

  3. 40 CFR 63.1407 - Non-reactor batch process vent provisions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 11 2011-07-01 2011-07-01 false Non-reactor batch process vent... § 63.1407 Non-reactor batch process vent provisions. (a) Emission standards. (1) Owners or operators of non-reactor batch process vents located at new or existing affected sources with 0.25 tons per year (0...

  4. 40 CFR 63.1430 - Process vent reporting and recordkeeping requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... is subject to the Group 1 batch process vent control requirements for nonepoxide HAP emissions from...) Records to demonstrate compliance. The owner or operator complying with the process vent control...: (1) When using a flare to comply with the process vent control requirements in § 63.1425(b)(2)(i), (c...

  5. 40 CFR 240.205-2 - Recommended procedures: Design.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ....205-2 Section 240.205-2 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES GUIDELINES FOR THE THERMAL PROCESSING OF SOLID WASTES Requirements and Recommended Procedures... air pollution control technology. (b) All emissions, including dust from vents, should be controlled. ...

  6. 40 CFR 240.205-2 - Recommended procedures: Design.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ....205-2 Section 240.205-2 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES GUIDELINES FOR THE THERMAL PROCESSING OF SOLID WASTES Requirements and Recommended Procedures... air pollution control technology. (b) All emissions, including dust from vents, should be controlled. ...

  7. 46 CFR 153.350 - Location of B/3 vent discharges.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Location of B/3 vent discharges. 153.350 Section 153.350 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS... Venting Systems § 153.350 Location of B/3 vent discharges. Except as prescribed in § 153.353, a B/3...

  8. 40 CFR 63.7925 - What emissions limitations and work practice standards must I meet for closed vent systems and...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL... Standards for Hazardous Air Pollutants: Site Remediation Closed Vent Systems and Control Devices § 63.7925...

  9. 40 CFR 63.7925 - What emissions limitations and work practice standards must I meet for closed vent systems and...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL... Standards for Hazardous Air Pollutants: Site Remediation Closed Vent Systems and Control Devices § 63.7925...

  10. 40 CFR 60.5416 - What are the initial and continuous cover and closed vent system inspection and monitoring...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false What are the initial and continuous cover and closed vent system inspection and monitoring requirements for my storage vessel and centrifugal compressor affected facility? 60.5416 Section 60.5416 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUE...

  11. 40 CFR 60.5416 - What are the initial and continuous cover and closed vent system inspection and monitoring...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false What are the initial and continuous cover and closed vent system inspection and monitoring requirements for my storage vessel and centrifugal compressor affected facility? 60.5416 Section 60.5416 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUE...

  12. 40 CFR 63.1333 - Additional requirements for performance testing.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... paragraphs (b)(1) and (b)(2) of this section. ER19JN00.041 Where: ERMBS = Emission rate of organic HAP or TOC from continuous process vents, kg/Mg product. Ei = Emission rate of organic HAP or TOC from continuous... hours in a year for control device j. Ei=Mass rate of TOC or total organic HAP at the inlet of control...

  13. 40 CFR 63.2480 - What requirements must I meet for equipment leaks?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... connectors at your affected source. (5) For pumps in light liquid service in an MCPU that has no continuous... connectors in gas/vapor and light liquid service at an existing source, you may elect to comply with the... in light liquid service in an MCPU that has no continuous process vents and is part of an existing...

  14. 40 CFR 63.2480 - What requirements must I meet for equipment leaks?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... connectors at your affected source. (5) For pumps in light liquid service in an MCPU that has no continuous... connectors in gas/vapor and light liquid service at an existing source, you may elect to comply with the... in light liquid service in an MCPU that has no continuous process vents and is part of an existing...

  15. 40 CFR 63.2480 - What requirements must I meet for equipment leaks?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... connectors at your affected source. (5) For pumps in light liquid service in an MCPU that has no continuous... connectors in gas/vapor and light liquid service at an existing source, you may elect to comply with the... in light liquid service in an MCPU that has no continuous process vents and is part of an existing...

  16. Joint analysis of deformation, gravity, and lava lake elevation reveals temporal variations in lava lake density at Kilauea Volcano, Hawaii

    NASA Astrophysics Data System (ADS)

    Carbone, Daniele; Poland, Michael; Patrick, Matthew

    2015-04-01

    We find a tight correlation between (i) changes in lava level within the summit eruptive vent at Kilauea Volcano, Hawaii, observed for at least 2 years since early 2011, and (ii) ground deformation in the vicinity of the vent. The observed correlation indicates that changing pressure within the shallow magma reservoir feeding the lava lake influences both deformation and lava level. However, those two parameters are related to chamber pressure through different properties, namely, the density of the lava filling the vent (for the lava level) and the size/position of the reservoir plus the elastic parameters of the host rock (for the deformation). Joint analyses in the time and frequency domains of lava level (determined from thermal camera imagery of the lava lake) and tilt measured on a borehole instrument (~2 km from the summit vent) reveal a good correlation throughout the studied period. The highest correlation occurs over periods ranging between 1 and 20 days. The ratio between lava level and tilt is not constant over time, however. Using data from a continuously recording gravimeter located near the rim of the summit eruptive vent, we demonstrate that the tilt-lava level ratio is controlled by the fluctuations in the density of the lava inside the vent (i.e., its degree of vesicularity). A second continuous gravimeter was installed near the summit eruptive vent in 2014, providing a new observation point for gravity change associated with summit lava lave activity to test models developed from the previously existing instrument. In addition, a continuous gravimeter was installed on the rim of the Puu Oo eruptive vent on Kilauea's East Rift Zone in 2013. Puu Oo is connected via the subvolcanic magma plumbing system to the summit eruptive vent and often deforms in concert with the summit. This growing network of continuously recording gravimeters at Kilauea can be used to examine correlations in gravity change associated with variations in eruptive activity across the volcano.

  17. 40 CFR 63.2465 - What requirements must I meet for process vents that emit hydrogen halide and halogen HAP or HAP...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... process vents that emit hydrogen halide and halogen HAP or HAP metals? 63.2465 Section 63.2465 Protection... Compliance Requirements § 63.2465 What requirements must I meet for process vents that emit hydrogen halide... section. (b) If any process vents within a process emit hydrogen halide and halogen HAP, you must...

  18. Monitoring biodegradation of diesel fuel in bioventing processes using in situ respiration rate.

    PubMed

    Lee, T H; Byun, I G; Kim, Y O; Hwang, I S; Park, T J

    2006-01-01

    An in situ measuring system of respiration rate was applied for monitoring biodegradation of diesel fuel in a bioventing process for bioremediation of diesel contaminated soil. Two laboratory-scale soil columns were packed with 5 kg of soil that was artificially contaminated by diesel fuel as final TPH (total petroleum hydrocarbon) concentration of 8,000 mg/kg soil. Nutrient was added to make a relative concentration of C:N:P = 100:10:1. One soil column was operated with continuous venting mode, and the other one with intermittent (6 h venting/6 h rest) venting mode. On-line O2 and CO2 gas measuring system was applied to measure O2 utilisation and CO2 production during biodegradation of diesel for 5 months. Biodegradation rate of TPH was calculated from respiration rate measured by the on-line gas measuring system. There were no apparent differences between calculated biodegradation rates from two columns with different venting modes. The variation of biodegradation rates corresponded well with trend of the remaining TPH concentrations comparing other biodegradation indicators, such as C17/pristane and C18/phytane ratio, dehydrogenase activity, and the ratio of hydrocarbon utilising bacteria to total heterotrophic bacteria. These results suggested that the on-line measuring system of respiration rate would be applied to monitoring biodegradation rate and to determine the potential applicability of bioventing process for bioremediation of oil contaminated soil.

  19. 40 CFR Table 4 to Subpart Vvvvvv... - Emission Limits and Compliance Requirements for Metal HAP Process Vents

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Requirements for Metal HAP Process Vents 4 Table 4 to Subpart VVVVVV of Part 63 Protection of Environment... of Part 63—Emission Limits and Compliance Requirements for Metal HAP Process Vents As required in § 63.11496(f), you must comply with the requirements for metal HAP process vents as shown in the...

  20. 40 CFR Table 7 to Subpart Ppp of... - Process Vents From Continuous Unit Operations-Monitoring, Recordkeeping, and Reporting Requirements

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... regeneration stream mass or volumetric flow during carbon bed regeneration cycle; and temperature of the carbon bed after regeneration (and within 15 minutes of completing any cooling cycle(s)) Maximum mass or...

  1. Long-times series of infrasonic records at open-vents volcanoes (Yasur volcano, Vanuatu, 2003-2014): the remarkable temporal stability of magma viscosity

    NASA Astrophysics Data System (ADS)

    Vergniolle, S.; Souty, V.; Zielinski, C.; Bani, P.; LE Pichon, A.; Lardy, M.; Millier, P.; Herry, P.; Todman, S.; Garaebiti, E.

    2017-12-01

    Open-vents volcanoes, often presenting series of Strombolian explosions of various intensity, are responding, although with a delay, to any changes in the degassing pattern, providing a quasi-direct route to processes at depth. Open-vents volcanoes display a persistent volcanic activity, although of variable intensity. Long-times series at open-vents volcanoes could therefore be key measurements to unravel physical processes at the origin of Strombolian explosions and be crucial for monitoring. Continuous infrasonic records can be used to estimate the gas volume expelled at the vent during explosions (bursting of a long slug). The gas volume of each explosion is deduced from a series of two successive integrations of acoustic pressure (monopole). Here we analysed more than 4 years of infrasonic records at Yasur volcano (Vanuatu), spanning between 2003 and 2014 and organised into 8 main quasi-continuous periods. The relationship between the gas volume of each explosion and its associated maximum positive acoustic pressure, a proxy for the inner gas overpressure at bursting, shows a remarkably stable trend over the 8 periods. Two main trends exists, one which covers the full range of acoustic pressures (called « strong explosions ») and the second which represents explosions with a large gas volume and mild acoustic pressure. The class of « strong explosions » clearly follows the model of Del Bello et al. (2012), which shows that the inner gas overpressure at bursting, here empirically measured by the maximum acoustic pressure, is proportional to the gas volume. Constrains on magma viscosity and conduit radius, are deduced from this trend and from the gas volume at the transition passive-active degassing. The remarkable stability of this trend over time suggests that 1) the magma viscosity is stable at the depth where gas overpressure is produced within the slug and 2) any potential changes in magma viscosity occur very close to the top of the magma column.

  2. 40 CFR 63.491 - Batch front-end process vents-recordkeeping requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (b)(2): (i) For an incinerator or non-combustion control device, the percent reduction of organic HAP... the process vent stream is introduced with combustion air or is used as a secondary fuel and is not... combustion device to control halogenated batch front-end process vents or halogenated aggregate batch vent...

  3. 40 CFR 63.1408 - Aggregate batch vent stream provisions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutant Emissions: Manufacture of Amino/Phenolic Resins § 63.1408 Aggregate batch vent stream provisions. (a) Emission standards. Owners or operators of...

  4. Distribution and chemistry of suspended particles from an active hydrothermal vent site on the Mid-Atlantic Ridge at 26°N

    NASA Astrophysics Data System (ADS)

    Trocine, Robert P.; Trefry, John H.

    1988-04-01

    Suspended particles were collected from an area of active hydrothermal venting at the Trans-Atlantic Geotraverse (TAG) Hydrothermal Field on the Mid-Atlantic Ridge and analyzed for Fe, Mn, Cd, Zn, Cu, V, Ni, Cr, Pb, Mg, Ca, Al and Si. Rapid advection of vent-derived precipitates produced a lens with total suspended matter (TSM) loadings of 14-60 μg/l at 200-700 m above the seafloor; TSM concentrations > 60 μg/l were observed only at near-vent sites. The distribution of suspended particles correlated well with increased dissolved Mn concentrations and particulate Fe values near the vent source. Particulate Fe values decreased linearly relative to TSM concentrations as hydrothermal precipitates mixed with background suspended matter. Near-vent precipitates were characterized by up to 35% Fe, 2% Zn, 0.6% Cu and > 100 μg/g Cd. In comparison to Fe, particulate Cd, Zn and Cu values decreased dramatically away from the vent source. This trend supports differential settling and/or dissolution of Cd-, Zn- and Cu-bearing phases. Particulate Mn and Fe values were inversely related with only 50 μg Mn/g in the near-vent particles. At near-vent sites, > 99% of the total Mn was in solution; this fraction decreased to 75-80% at background TSM values. In contrast to Cd, Zn and Cu, particulate V levels show a continuous, linear decrease with particulate Fe values. This trend is explained by adsorption of V on Fe-oxides in the vent plume. Scavenging of Cr, Pb and Mg by hydrothermal precipitates is also suggested by the data. Nickel and Al values were low in near-vent particles at < 100 and < 3 μg/g, respectively. The complementary behavior of dissolved Mn and particulate trace metals provides a useful framework for studying broad aspects of hydrothermal plume processes.

  5. 40 CFR 63.1361 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... hatches, sampling ports, and gauge wells provided that each opening is closed when not in use. Examples of... uncontrolled organic HAP emissions from the sum of all process vents are greater than or equal to 0.15 Mg/yr... vents are greater than or equal to 6.8 Mg/yr. Group 2 process vent means any process vent that does not...

  6. 40 CFR 63.1361 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... hatches, sampling ports, and gauge wells provided that each opening is closed when not in use. Examples of... uncontrolled organic HAP emissions from the sum of all process vents are greater than or equal to 0.15 Mg/yr... vents are greater than or equal to 6.8 Mg/yr. Group 2 process vent means any process vent that does not...

  7. Explosive volcanism on Mercury: Analysis of vent and deposit morphology and modes of eruption

    NASA Astrophysics Data System (ADS)

    Jozwiak, Lauren M.; Head, James W.; Wilson, Lionel

    2018-03-01

    The MESSENGER mission revealed, for the first time, conclusive evidence of explosive volcanism on Mercury. Several previous works have cataloged the appearance and location of explosive volcanism on the planet using a variety of identifying characteristics, including vent presence and deposit color as seen in multispectral image mosaics. We present here a comprehensive catalog of vents of likely volcanic origin; our classification scheme emphasizes vent morphology. We have analyzed the morphologies of all vents in our catalog, and recognize three main morphologies: "simple vent", "pit vent", and "vent-with-mound". The majority of vents we identify are located within impact craters. The spatial distribution of vents does not correlate with the locations of volcanic smooth plains deposits, in contrast to the Moon, nor do vents correlate with the locations of large impact basins (except for the Caloris and Tolstoj basins). Using the degradation state of the vent host crater as a proxy for maximum age, we suggest that vent formation has been active through the Mansurian and into the Kuiperian periods, although the majority of vents were likely formed much earlier in mercurian history. The morphologies and locations of vents are used to investigate a set of plausible formation geometries. We find that the most likely and most prevalent formation geometry is that of a dike, stalled at depth, which then explosively vents to the surface. We compare the vent and deposit size of mercurian pyroclastic deposits with localized and regional lunar pyroclastic deposits, and find a range of possible eruption energies and corresponding variations in eruption style. Localized lunar pyroclastic deposits and the majority of mercurian pyroclastic deposits show evidence for eruption that is consistent with the magmatic foam at the top of a dike reaching a critical gas volume fraction. A subset of mercurian vents, including the prominent Copland-Rachmaninoff vent to the northeast of the Rachmaninoff basin, indicates eruption at enhanced gas volume fractions. This subset of vents shows a similar eruptive behavior to the lunar Orientale dark mantle ring deposit, suggesting that the dikes that formed these vents and deposits on Mercury underwent some form of additional volatile build-up either through crustal volatile incorporation or magma convection within the dike. There also exists a population of mercurian vents that no longer retain a visible associated pyroclastic deposit; we hypothesize that the visible signature of the pyroclastic deposit has been lost through space weathering and regolith mixing processes. Together, these results provide a comprehensive analysis of explosive volcanism on Mercury, and inform continued research on the thermal history of Mercury and magma composition and evolution.

  8. 40 CFR Table 2 to Subpart Ffff of... - Emission Limits and Work Practice Standards for Batch Process Vents

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...: Miscellaneous Organic Chemical Manufacturing Pt. 63, Subpt. FFFF, Table 2 Table 2 to Subpart FFFF of Part 63... vents a. Reduce collective uncontrolled organic HAP emissions from the sum of all batch process vents... applicable. b. Reduce collective uncontrolled organic HAP emissions from the sum of all batch process vents...

  9. 40 CFR Table 2 to Subpart Ffff of... - Emission Limits and Work Practice Standards for Batch Process Vents

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...: Miscellaneous Organic Chemical Manufacturing Pt. 63, Subpt. FFFF, Table 2 Table 2 to Subpart FFFF of Part 63... vents a. Reduce collective uncontrolled organic HAP emissions from the sum of all batch process vents... applicable. b. Reduce collective uncontrolled organic HAP emissions from the sum of all batch process vents...

  10. 40 CFR Table 20 to Subpart Uuu of... - Continuous Compliance With Organic HAP Emission Limits for Catalytic Reforming Units

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... uncontrolled emissions of total organic compounds (TOC) or nonmethane TOC from your process vent by 98 percent... of TOC or nonmethane TOC; or maintaining a TOC or nonmethane TOC concentration of not more than 20...

  11. 40 CFR 63.2520 - What reports must I submit and when?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Miscellaneous Organic Chemical... from streams that contain energetics and organic peroxides, and rationale for why meeting the emission... lb/yr, the total uncontrolled organic HAP emissions from the batch process vents in an MCPU will be...

  12. 40 CFR 63.644 - Monitoring provisions for miscellaneous process vents.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... to a thermocouple, an ultraviolet beam sensor, or an infrared sensor) capable of continuously... the equipment will monitor accurately. (1) Where an incinerator is used, a temperature monitoring... incinerator is used, a temperature monitoring device shall be installed in the firebox or in the ductwork...

  13. 40 CFR 63.644 - Monitoring provisions for miscellaneous process vents.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... to a thermocouple, an ultraviolet beam sensor, or an infrared sensor) capable of continuously... the equipment will monitor accurately. (1) Where an incinerator is used, a temperature monitoring... incinerator is used, a temperature monitoring device shall be installed in the firebox or in the ductwork...

  14. 40 CFR 63.1324 - Batch process vents-monitoring equipment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... device (including but not limited to a thermocouple, ultra-violet beam sensor, or infrared sensor... temperature monitoring device equipped with a continuous recorder is required. (i) Where an incinerator other than a catalytic incinerator is used, the temperature monitoring device shall be installed in the...

  15. 40 CFR 63.114 - Process vent provisions-monitoring requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... but not limited to a thermocouple, ultra-violet beam sensor, or infrared sensor) capable of... accurately. (1) Where an incinerator is used, a temperature monitoring device equipped with a continuous recorder is required. (i) Where an incinerator other than a catalytic incinerator is used, a temperature...

  16. 40 CFR 63.644 - Monitoring provisions for miscellaneous process vents.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... to a thermocouple, an ultraviolet beam sensor, or an infrared sensor) capable of continuously... the equipment will monitor accurately. (1) Where an incinerator is used, a temperature monitoring... incinerator is used, a temperature monitoring device shall be installed in the firebox or in the ductwork...

  17. 40 CFR 63.114 - Process vent provisions-monitoring requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... but not limited to a thermocouple, ultra-violet beam sensor, or infrared sensor) capable of... accurately. (1) Where an incinerator is used, a temperature monitoring device equipped with a continuous recorder is required. (i) Where an incinerator other than a catalytic incinerator is used, a temperature...

  18. 40 CFR 63.114 - Process vent provisions-monitoring requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... but not limited to a thermocouple, ultra-violet beam sensor, or infrared sensor) capable of... accurately. (1) Where an incinerator is used, a temperature monitoring device equipped with a continuous recorder is required. (i) Where an incinerator other than a catalytic incinerator is used, a temperature...

  19. 40 CFR Table 4 to Subpart Uuuu of... - Requirements for Performance Tests

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... of the initial compliance demonstration; or (2) carbon disulfide and/or hydrogen sulfide CEMS, as... toluene storage vessel a. each existing or new cellophane operation i. measure toluene emissions (1) EPA... continuous storage vessel vents and combinations of batch and continuous storage vessel vents at normal...

  20. 40 CFR 63.1104 - Process vents from continuous unit operations: applicability assessment procedures and methods.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... accordance with the applicable weight-percent, TOC concentration, or organic HAP concentration requirement in... rate, regulated organic HAP concentration, total organic HAP or TOC concentration, heating value, and... volumetric flow rate, regulated organic HAP concentration, total organic HAP or TOC concentration, and any...

  1. 40 CFR Table 1 to Subpart Bbbbb of... - Requirements for Performance Tests

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Semiconductor... necessary. 2. Process vent stream a. Measure organic and inorganic HAP concentration (two method option) i... simultaneous sampling at inlet and outlet of control device and analyze for same organic and inorganic HAP at...

  2. 40 CFR Table 1 to Subpart Bbbbb of... - Requirements for Performance Tests

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Semiconductor... necessary. 2. Process vent stream a. Measure organic and inorganic HAP concentration (two method option) i... simultaneous sampling at inlet and outlet of control device and analyze for same organic and inorganic HAP at...

  3. 40 CFR 63.114 - Process vent provisions-monitoring requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., temperature monitoring devices shall be installed in the gas stream immediately before and after the catalyst... but not limited to a thermocouple, ultra-violet beam sensor, or infrared sensor) capable of... monitoring device in the firebox equipped with a continuous recorder. This requirement does not apply to gas...

  4. 40 CFR 63.114 - Process vent provisions-monitoring requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., temperature monitoring devices shall be installed in the gas stream immediately before and after the catalyst... but not limited to a thermocouple, ultra-violet beam sensor, or infrared sensor) capable of... monitoring device in the firebox equipped with a continuous recorder. This requirement does not apply to gas...

  5. 40 CFR 63.1317 - PET and polystyrene affected sources-monitoring provisions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 12 2012-07-01 2011-07-01 true PET and polystyrene affected sources-monitoring provisions. 63.1317 Section 63.1317 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 63.1317 PET and polystyrene affected sources—monitoring provisions. Continuous process vents using a...

  6. 40 CFR 63.1317 - PET and polystyrene affected sources-monitoring provisions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 11 2011-07-01 2011-07-01 false PET and polystyrene affected sources-monitoring provisions. 63.1317 Section 63.1317 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 63.1317 PET and polystyrene affected sources—monitoring provisions. Continuous process vents using a...

  7. 40 CFR 63.1317 - PET and polystyrene affected sources-monitoring provisions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true PET and polystyrene affected sources-monitoring provisions. 63.1317 Section 63.1317 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 63.1317 PET and polystyrene affected sources—monitoring provisions. Continuous process vents using a...

  8. 40 CFR 63.1032 - Sampling connection systems standards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) [Reserved] (3) Be designed and operated to capture and transport all the purged process fluid to a control... (CONTINUED) National Emission Standards for Equipment Leaks-Control Level 2 Standards § 63.1032 Sampling... design and operation. Each closed-purge, closed-loop, or closed vent system as required in paragraph (b...

  9. 40 CFR 63.1032 - Sampling connection systems standards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) [Reserved] (3) Be designed and operated to capture and transport all the purged process fluid to a control... (CONTINUED) National Emission Standards for Equipment Leaks-Control Level 2 Standards § 63.1032 Sampling... design and operation. Each closed-purge, closed-loop, or closed vent system as required in paragraph (b...

  10. 40 CFR 98.53 - Calculating GHG emissions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Adipic Acid Production § 98.53 Calculating GHG emissions. (a) You must determine annual N2O emissions from adipic acid production according to paragraphs (a)(1) or... must conduct the test on the vent stream from the nitric acid oxidation step of the process, referred...

  11. 40 CFR 98.53 - Calculating GHG emissions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Adipic Acid Production § 98.53 Calculating GHG emissions. (a) You must determine annual N2O emissions from adipic acid production according to paragraphs (a)(1) or... must conduct the test on the vent stream from the nitric acid oxidation step of the process, referred...

  12. 40 CFR 98.53 - Calculating GHG emissions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Adipic Acid Production § 98.53 Calculating GHG emissions. (a) You must determine annual N2O emissions from adipic acid production according to paragraphs (a)(1) or... must conduct the test on the vent stream from the nitric acid oxidation step of the process, referred...

  13. 40 CFR 63.489 - Batch front-end process vents-monitoring equipment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... device (including, but not limited to, a thermocouple, ultra-violet beam sensor, or infrared sensor... temperature monitoring device equipped with a continuous recorder is required. (i) Where an incinerator other than a catalytic incinerator is used, the temperature monitoring device shall be installed in the...

  14. 40 CFR 63.489 - Batch front-end process vents-monitoring equipment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... device (including, but not limited to, a thermocouple, ultra-violet beam sensor, or infrared sensor... temperature monitoring device equipped with a continuous recorder is required. (i) Where an incinerator other than a catalytic incinerator is used, the temperature monitoring device shall be installed in the...

  15. 40 CFR 63.489 - Batch front-end process vents-monitoring equipment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... device (including, but not limited to, a thermocouple, ultra-violet beam sensor, or infrared sensor... temperature monitoring device equipped with a continuous recorder is required. (i) Where an incinerator other than a catalytic incinerator is used, the temperature monitoring device shall be installed in the...

  16. 40 CFR 60.456 - Test methods and procedures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Section 60.456 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... § 60.453. (2) Method 25 for the measurement of the VOC concentration in the gas stream vent. (3) Method... sampling times or smaller volumes, when necessitated by process variables or other factors, may be approved...

  17. 40 CFR 63.8246 - How do I demonstrate continuous compliance with the emission limitations and work practice...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Hazardous Air Pollutants: Mercury Emissions From Mercury Cell Chlor-Alkali Plants Continuous Compliance... practice standards? (a) By-product hydrogen streams and end box ventilation system vents. (1) For all by-product hydrogen streams and all end box ventilation system vents, if applicable, you must demonstrate...

  18. 40 CFR 63.8246 - How do I demonstrate continuous compliance with the emission limitations and work practice...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Hazardous Air Pollutants: Mercury Emissions From Mercury Cell Chlor-Alkali Plants Continuous Compliance... practice standards? (a) By-product hydrogen streams and end box ventilation system vents. (1) For all by-product hydrogen streams and all end box ventilation system vents, if applicable, you must demonstrate...

  19. 40 CFR 63.8246 - How do I demonstrate continuous compliance with the emission limitations and work practice...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Hazardous Air Pollutants: Mercury Emissions From Mercury Cell Chlor-Alkali Plants Continuous Compliance... practice standards? (a) By-product hydrogen streams and end box ventilation system vents. (1) For all by-product hydrogen streams and all end box ventilation system vents, if applicable, you must demonstrate...

  20. 40 CFR 63.8246 - How do I demonstrate continuous compliance with the emission limitations and work practice...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Hazardous Air Pollutants: Mercury Emissions From Mercury Cell Chlor-Alkali Plants Continuous Compliance... practice standards? (a) By-product hydrogen streams and end box ventilation system vents. (1) For all by-product hydrogen streams and all end box ventilation system vents, if applicable, you must demonstrate...

  1. 40 CFR 63.8246 - How do I demonstrate continuous compliance with the emission limitations and work practice...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Hazardous Air Pollutants: Mercury Emissions From Mercury Cell Chlor-Alkali Plants Continuous Compliance... practice standards? (a) By-product hydrogen streams and end box ventilation system vents. (1) For all by-product hydrogen streams and all end box ventilation system vents, if applicable, you must demonstrate...

  2. 40 CFR 63.487 - Batch front-end process vents-reference control technology.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... § 63.487 Batch front-end process vents—reference control technology. (a) Batch front-end process vents... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Batch front-end process vents-reference control technology. 63.487 Section 63.487 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

  3. 40 CFR 63.1321 - Batch process vents provisions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins § 63.1321 Batch process vents..., owners and operators of new and existing affected sources with batch process vents shall comply with the... applicable reporting requirements in § 63.1327. (b) New SAN batch affected sources. Owners and operators of...

  4. 40 CFR 63.764 - General standards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... in paragraphs (c)(1) through (3) of this section. (1) For each glycol dehydration unit process vent... requirements for glycol dehydration unit process vents specified in § 63.765; (ii) The owner or operator shall... requirements for glycol dehydration unit process vents specified in § 63.765; (ii) The monitoring requirements...

  5. 40 CFR 63.764 - General standards.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... in paragraphs (c)(1) through (3) of this section. (1) For each glycol dehydration unit process vent... requirements for glycol dehydration unit process vents specified in § 63.765; (ii) The owner or operator shall... requirements for glycol dehydration unit process vents specified in § 63.765; (ii) The monitoring requirements...

  6. 40 CFR 63.764 - General standards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... in paragraphs (c)(1) through (3) of this section. (1) For each glycol dehydration unit process vent... requirements for glycol dehydration unit process vents specified in § 63.765; (ii) The owner or operator shall... requirements for glycol dehydration unit process vents specified in § 63.765; (ii) The monitoring requirements...

  7. 40 CFR 63.1275 - Glycol dehydration unit process vent standards.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 12 2014-07-01 2014-07-01 false Glycol dehydration unit process vent... Storage Facilities § 63.1275 Glycol dehydration unit process vent standards. (a) This section applies to each glycol dehydration unit subject to this subpart that must be controlled for air emissions as...

  8. 40 CFR 63.1275 - Glycol dehydration unit process vent standards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 12 2013-07-01 2013-07-01 false Glycol dehydration unit process vent... Storage Facilities § 63.1275 Glycol dehydration unit process vent standards. (a) This section applies to each glycol dehydration unit subject to this subpart that must be controlled for air emissions as...

  9. 40 CFR 63.764 - General standards.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... in paragraphs (c)(1) through (3) of this section. (1) For each glycol dehydration unit process vent... requirements for glycol dehydration unit process vents specified in § 63.765; (ii) The owner or operator shall... requirements for glycol dehydration unit process vents specified in § 63.765; (ii) The monitoring requirements...

  10. 40 CFR 63.764 - General standards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... in paragraphs (c)(1) through (3) of this section. (1) For each glycol dehydration unit process vent... requirements for glycol dehydration unit process vents specified in § 63.765; (ii) The owner or operator shall... requirements for glycol dehydration unit process vents specified in § 63.765; (ii) The monitoring requirements...

  11. 40 CFR 63.1016 - Alternative means of emission limitation: Enclosed-vented process units.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Alternative means of emission limitation: Enclosed-vented process units. 63.1016 Section 63.1016 Protection of Environment ENVIRONMENTAL... § 63.1016 Alternative means of emission limitation: Enclosed-vented process units. (a) Use of closed...

  12. 40 CFR 63.1016 - Alternative means of emission limitation: Enclosed-vented process units.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 10 2011-07-01 2011-07-01 false Alternative means of emission limitation: Enclosed-vented process units. 63.1016 Section 63.1016 Protection of Environment ENVIRONMENTAL... § 63.1016 Alternative means of emission limitation: Enclosed-vented process units. (a) Use of closed...

  13. 40 CFR 63.113 - Process vent provisions-reference control technology.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 10 2012-07-01 2012-07-01 false Process vent provisions-reference control technology. 63.113 Section 63.113 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 63.113 Process vent provisions—reference control technology. (a) The owner or operator of a Group 1...

  14. 40 CFR 63.113 - Process vent provisions-reference control technology.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 10 2013-07-01 2013-07-01 false Process vent provisions-reference control technology. 63.113 Section 63.113 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 63.113 Process vent provisions—reference control technology. (a) The owner or operator of a Group 1...

  15. 40 CFR 63.113 - Process vent provisions-reference control technology.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 9 2011-07-01 2011-07-01 false Process vent provisions-reference control technology. 63.113 Section 63.113 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 63.113 Process vent provisions—reference control technology. (a) The owner or operator of a Group 1...

  16. 40 CFR 63.113 - Process vent provisions-reference control technology.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 10 2014-07-01 2014-07-01 false Process vent provisions-reference control technology. 63.113 Section 63.113 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 63.113 Process vent provisions—reference control technology. (a) The owner or operator of a Group 1...

  17. 40 CFR 63.113 - Process vent provisions-reference control technology.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Process vent provisions-reference control technology. 63.113 Section 63.113 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 63.113 Process vent provisions—reference control technology. (a) The owner or operator of a Group 1...

  18. 40 CFR 63.7885 - What are the general standards I must meet for my affected process vents?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... meet for my affected process vents? 63.7885 Section 63.7885 Protection of Environment ENVIRONMENTAL... Remediation General Standards § 63.7885 What are the general standards I must meet for my affected process...) You determine for the remediation material treated or managed by the process vented through the...

  19. 40 CFR 63.7885 - What are the general standards I must meet for my affected process vents?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... meet for my affected process vents? 63.7885 Section 63.7885 Protection of Environment ENVIRONMENTAL... Remediation General Standards § 63.7885 What are the general standards I must meet for my affected process...) You determine for the remediation material treated or managed by the process vented through the...

  20. 40 CFR 63.7885 - What are the general standards I must meet for my affected process vents?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... meet for my affected process vents? 63.7885 Section 63.7885 Protection of Environment ENVIRONMENTAL... Remediation General Standards § 63.7885 What are the general standards I must meet for my affected process...) You determine for the remediation material treated or managed by the process vented through the...

  1. 40 CFR 63.7885 - What are the general standards I must meet for my affected process vents?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... meet for my affected process vents? 63.7885 Section 63.7885 Protection of Environment ENVIRONMENTAL... Remediation General Standards § 63.7885 What are the general standards I must meet for my affected process...) You determine for the remediation material treated or managed by the process vented through the...

  2. Analyzing the continuous volcanic tremors detected during the 2015 phreatic eruption of the Hakone volcano

    NASA Astrophysics Data System (ADS)

    Yukutake, Yohei; Honda, Ryou; Harada, Masatake; Doke, Ryosuke; Saito, Tatsuhiko; Ueno, Tomotake; Sakai, Shin'ichi; Morita, Yuichi

    2017-12-01

    In the present study, we analyze the seismic signals from a continuous volcanic tremor that occurred during a small phreatic eruption of the Hakone volcano, in the Owakudani geothermal region of central Japan, on June 29, 2015. The signals were detected for 2 days, from June 29 to July 1, at stations near the vents. The frequency component of the volcanic tremors showed a broad peak within 1-6 Hz. The characteristics of the frequency component did not vary with time and were independent of the amplitude of the tremor. The largest amplitude was observed at the end of the tremor activity, 2 days after the onset of the eruption. We estimated the location of the source using a cross-correlation analysis of waveform envelopes. The locations of volcanic tremors are determined near the vents of eruption and the surface, with the area of the upper extent of an open crack estimated using changes in the tilt. The duration-amplitude distribution of the volcanic tremor was consistent with the exponential scaling law rather than the power law, suggesting a scale-bound source process. This result suggests that the volcanic tremor originated from a similar physical process occurring practically in the same place. The increment of the tremor amplitude was coincident with the occurrence of impulsive infrasonic waves and vent formations. High-amplitude seismic phases were observed prior to the infrasonic onsets. The time difference between the seismic and infrasonic onsets can be explained assuming a common source located at the vent. This result suggests that both seismic and infrasonic waves are generated when a gas slug bursts at that location. The frequency components of the seismic phases observed just before the infrasonic onset were generally consistent with those of the tremor signals without infrasonic waves. The burst of a gas slug at the surface vent may be a reasonable model for the generation mechanism of the volcanic tremor and the occurrence of impulsive infrasonic signals.[Figure not available: see fulltext.

  3. 40 CFR Table 3 to Subpart Ooo of... - Batch Process Vent Monitoring Requirements

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) temperature Continuous records as specified in § 63.1416(d). a Carbon adsorber a Total regeneration steam flow or nitrogen flow, or pressure (gauge or absolute) during carbon bed regeneration cycle(s), and Record the total regeneration steam flow or nitrogen flow, or pressure for each carbon bed regeneration cycle...

  4. 40 CFR Table 3 to Subpart Ooo of... - Batch Process Vent Monitoring Requirements

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) temperature Continuous records as specified in § 63.1416(d). a Carbon adsorber a Total regeneration steam flow or nitrogen flow, or pressure (gauge or absolute) during carbon bed regeneration cycle(s), and Record the total regeneration steam flow or nitrogen flow, or pressure for each carbon bed regeneration cycle...

  5. 40 CFR 63.983 - Closed vent systems.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Closed vent systems. 63.983 Section 63... Emission Standards for Closed Vent Systems, Control Devices, Recovery Devices and Routing to a Fuel Gas System or a Process § 63.983 Closed vent systems. (a) Closed vent system equipment and operating...

  6. 40 CFR 63.1426 - Process vent requirements for determining organic HAP concentration, control efficiency, and...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Production § 63.1426 Process vent requirements for determining organic HAP concentration, control efficiency..., total organic HAP, or as TOC minus methane and ethane according to the procedures specified. When... methane and ethane) concentrations in all process vent streams and primary and secondary fuels introduced...

  7. 40 CFR 63.1275 - Glycol dehydration unit process vent standards.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 12 2012-07-01 2011-07-01 true Glycol dehydration unit process vent... Facilities § 63.1275 Glycol dehydration unit process vent standards. (a) This section applies to each glycol dehydration unit subject to this subpart with an actual annual average natural gas flowrate equal to or...

  8. 40 CFR 63.1275 - Glycol dehydration unit process vent standards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Glycol dehydration unit process vent... Facilities § 63.1275 Glycol dehydration unit process vent standards. (a) This section applies to each glycol dehydration unit subject to this subpart with an actual annual average natural gas flowrate equal to or...

  9. 40 CFR 63.765 - Glycol dehydration unit process vent standards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 11 2013-07-01 2013-07-01 false Glycol dehydration unit process vent... Facilities § 63.765 Glycol dehydration unit process vent standards. (a) This section applies to each glycol dehydration unit subject to this subpart that must be controlled for air emissions as specified in either...

  10. 40 CFR 63.765 - Glycol dehydration unit process vent standards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 10 2011-07-01 2011-07-01 false Glycol dehydration unit process vent... Facilities § 63.765 Glycol dehydration unit process vent standards. (a) This section applies to each glycol dehydration unit subject to this subpart with an actual annual average natural gas flowrate equal to or...

  11. 40 CFR 63.765 - Glycol dehydration unit process vent standards.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 11 2014-07-01 2014-07-01 false Glycol dehydration unit process vent... Facilities § 63.765 Glycol dehydration unit process vent standards. (a) This section applies to each glycol dehydration unit subject to this subpart that must be controlled for air emissions as specified in either...

  12. 40 CFR 63.765 - Glycol dehydration unit process vent standards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Glycol dehydration unit process vent... Facilities § 63.765 Glycol dehydration unit process vent standards. (a) This section applies to each glycol dehydration unit subject to this subpart with an actual annual average natural gas flowrate equal to or...

  13. 40 CFR 63.1275 - Glycol dehydration unit process vent standards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 11 2011-07-01 2011-07-01 false Glycol dehydration unit process vent... Facilities § 63.1275 Glycol dehydration unit process vent standards. (a) This section applies to each glycol dehydration unit subject to this subpart with an actual annual average natural gas flowrate equal to or...

  14. 40 CFR 63.765 - Glycol dehydration unit process vent standards.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 11 2012-07-01 2012-07-01 false Glycol dehydration unit process vent... Facilities § 63.765 Glycol dehydration unit process vent standards. (a) This section applies to each glycol dehydration unit subject to this subpart with an actual annual average natural gas flowrate equal to or...

  15. 40 CFR 63.117 - Process vent provisions-reporting and recordkeeping requirements for group and TRE determinations...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Vents, Storage Vessels, Transfer Operations, and Wastewater § 63.117 Process vent provisions—reporting... incinerators, boilers or process heaters specified in table 3 of this subpart, and averaged over the same time... content determinations, flow rate measurements, and exit velocity determinations made during the...

  16. 40 CFR 63.117 - Process vent provisions-reporting and recordkeeping requirements for group and TRE determinations...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Vents, Storage Vessels, Transfer Operations, and Wastewater § 63.117 Process vent provisions—reporting... incinerators, boilers or process heaters specified in table 3 of this subpart, and averaged over the same time... content determinations, flow rate measurements, and exit velocity determinations made during the...

  17. 40 CFR 87.11 - Standard for fuel venting emissions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... PROGRAMS (CONTINUED) Definitions. Engine Fuel Venting Emissions (New and In-Use Aircraft Gas Turbine... into the atmosphere from any new or in-use aircraft gas turbine engine subject to the subpart. This...

  18. 40 CFR 63.11930 - What requirements must I meet for closed vent systems?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... emission limits in Table 1 or 2 to this subpart to a control device, you must use a closed vent system and... emission limits in Table 1 or 2 to this subpart. You must maintain the records specified in paragraph (g)(1... (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE...

  19. Features of lava lake filling and draining and their implications for eruption dynamics

    USGS Publications Warehouse

    Stovall, W.K.; Houghton, Bruce F.; Harris, A.J.L.; Swanson, D.A.

    2009-01-01

    Lava lakes experience filling, circulation, and often drainage depending upon the style of activity and location of the vent. Features formed by these processes have proved difficult to document due to dangerous conditions during the eruption, inaccessibility, and destruction of features during lake drainage. Kilauea Iki lava lake, Kilauea, Hawai'i, preserves many such features, because lava ponded in a pre-existing crater adjacent to the vent and eventually filled to the level of, and interacted with, the vent and lava fountains. During repeated episodes, a cyclic pattern of lake filling to above vent level, followed by draining back to vent level, preserved features associated with both filling and draining. Field investigations permit us to describe the characteristic features associated with lava lakes on length scales ranging from centimeters to hundreds of meters in a fashion analogous to descriptions of lava flows. Multiple vertical rinds of lava coating the lake walls formed during filling as the lake deepened and lava solidified against vertical faces. Drainage of the lake resulted in uneven formation of roughly horizontal lava shelves on the lakeward edge of the vertical rinds; the shelves correlate with stable, staggered lake stands. Shelves either formed as broken relict slabs of lake crust that solidified in contact with the wall or by accumulation, accretion, and widening at the lake surface in a dynamic lateral flow regime. Thin, upper lava shelves reflect an initially dynamic environment, in which rapid lake lowering was replaced by slower and more staggered drainage with the formation of thicker, more laterally continuous shelves. At all lava lakes experiencing stages of filling and draining these processes may occur and result in the formation of similar sets of features. ?? Springer-Verlag 2009.

  20. 40 CFR 63.118 - Process vent provisions-periodic reporting and recordkeeping requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 9 2011-07-01 2011-07-01 false Process vent provisions-periodic..., and Wastewater § 63.118 Process vent provisions—periodic reporting and recordkeeping requirements. (a... table 3 of this subpart or specified by the Administrator in accordance with § 63.114(c) and § 63.117(e...

  1. 40 CFR 63.118 - Process vent provisions-periodic reporting and recordkeeping requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 10 2013-07-01 2013-07-01 false Process vent provisions-periodic..., and Wastewater § 63.118 Process vent provisions—periodic reporting and recordkeeping requirements. (a... table 3 of this subpart or specified by the Administrator in accordance with §§ 63.114(c) and 63.117(e...

  2. 40 CFR 63.118 - Process vent provisions-periodic reporting and recordkeeping requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 10 2012-07-01 2012-07-01 false Process vent provisions-periodic..., and Wastewater § 63.118 Process vent provisions—periodic reporting and recordkeeping requirements. (a... table 3 of this subpart or specified by the Administrator in accordance with §§ 63.114(c) and 63.117(e...

  3. 40 CFR 63.644 - Monitoring provisions for miscellaneous process vents.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) of this section, each owner or operator of a Group 1 miscellaneous process vent that uses a... detecting the presence of a pilot flame is required. (3) Any boiler or process heater with a design heat... less than 44 megawatts design heat capacity where the vent stream is not introduced into the flame zone...

  4. 40 CFR 63.644 - Monitoring provisions for miscellaneous process vents.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) of this section, each owner or operator of a Group 1 miscellaneous process vent that uses a... detecting the presence of a pilot flame is required. (3) Any boiler or process heater with a design heat... less than 44 megawatts design heat capacity where the vent stream is not introduced into the flame zone...

  5. 40 CFR Table 7 to Subpart Ppp of... - Process Vents From Continuous Unit Operations-Monitoring, Recordkeeping, and Reporting Requirements

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... absorbent is used. Condenser Exit temperature Maximum temperature. Carbon adsorber Total regeneration stream mass or volumetric flow during carbon bed regeneration cycle; and temperature of the carbon bed after regeneration (and within 15 minutes of completing any cooling cycle(s)) Maximum mass or volumetric flow; and...

  6. 40 CFR Table 7 to Subpart Ppp of... - Process Vents From Continuous Unit Operations-Monitoring, Recordkeeping, and Reporting Requirements

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... absorbent is used. Condenser Exit temperature Maximum temperature. Carbon adsorber Total regeneration stream mass or volumetric flow during carbon bed regeneration cycle; and temperature of the carbon bed after regeneration (and within 15 minutes of completing any cooling cycle(s)) Maximum mass or volumetric flow; and...

  7. 40 CFR Table 7 to Subpart Ppp of... - Process Vents From Continuous Unit Operations-Monitoring, Recordkeeping, and Reporting Requirements

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... absorbent is used. Condenser Exit temperature Maximum temperature. Carbon adsorber Total regeneration stream mass or volumetric flow during carbon bed regeneration cycle; and temperature of the carbon bed after regeneration (and within 15 minutes of completing any cooling cycle(s)) Maximum mass or volumetric flow; and...

  8. 40 CFR Table 7 to Subpart Ppp of... - Operating Parameters for Which Monitoring Levels Are Required To Be Established for Process Vent...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutant Emissions for Polyether Polyols Production Pt. 63, Subpt. PPP, Table 7... regeneration stream mass or volumetric flow during carbon bed regeneration cycle; and temperature of the carbon...

  9. 40 CFR 63.1413 - Compliance demonstration procedures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... liquids, other than fuels, received by the control device. (i) For a scrubber, the design evaluation shall... scrubbing liquid. The design evaluation shall establish the design exhaust vent stream organic compound... process vent and the overall percent reduction for the collection of non-reactor batch process vents...

  10. 40 CFR 63.2465 - What requirements must I meet for process vents that emit hydrogen halide and halogen HAP or HAP...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... process vents that emit hydrogen halide and halogen HAP or HAP metals? 63.2465 Section 63.2465 Protection... hydrogen halide and halogen HAP or HAP metals? (a) You must meet each emission limit in Table 3 to this...) of this section. (b) If any process vents within a process emit hydrogen halide and halogen HAP, you...

  11. 40 CFR 63.2465 - What requirements must I meet for process vents that emit hydrogen halide and halogen HAP or HAP...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... process vents that emit hydrogen halide and halogen HAP or HAP metals? 63.2465 Section 63.2465 Protection... hydrogen halide and halogen HAP or HAP metals? (a) You must meet each emission limit in Table 3 to this...) of this section. (b) If any process vents within a process emit hydrogen halide and halogen HAP, you...

  12. 40 CFR 63.2465 - What requirements must I meet for process vents that emit hydrogen halide and halogen HAP or HAP...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... process vents that emit hydrogen halide and halogen HAP or HAP metals? 63.2465 Section 63.2465 Protection... hydrogen halide and halogen HAP or HAP metals? (a) You must meet each emission limit in Table 3 to this...) of this section. (b) If any process vents within a process emit hydrogen halide and halogen HAP, you...

  13. 40 CFR 63.115 - Process vent provisions-methods and procedures for process vent group determination.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 2 process vent definition of this subpart shall measure either total organic HAP or TOC... either TOC (minus methane and ethane) or organic HAP shall be calculated according to paragraph (c)(3)(ii)(A) or (c)(3)(ii)(B) of this section as applicable. (A) The TOC concentration (CTOC) is the sum of...

  14. Continuing Evolution of the Hydrothermal System at the RIDGE2000 ISS, 9-10° N EPR: 1991-2004

    NASA Astrophysics Data System (ADS)

    von Damm, K. L.; Parker, C. M.; Beers, K. A.; Hyde, A. A.

    2004-12-01

    We have been studying the evolution of the chemical composition of the mid-ocean ridge (MOR) hydrothermal system on the East Pacific Rise from 9° 46-51'N since it was impacted by volcanic eruptions in 1991/2. We have been using the chemical and temperature data to infer the processes that are occurring subseafloor in the upper oceanic crust. As of March 2004, the chemical compositions of the vent fluids from this site have not yet stabilized. This observation is helping us to better understand not only the impact of magmatic events on these systems, but also the time scales on which they occur. Centered at the RIDGE2000 ISS "bull's-eye" at 9° 50'N we have noted a striking increase in the number of hydrothermal vents as well as in their measured fluid temperatures beginning after ~2000. In November 2003 we first noted the formation of a black smoker vent at the Tica site (measured T=342° C). In March 2004 we identified another new area of robust flow near the Bio9 vents at 9° 50'N, the 'Alvinellid Mat,' that we anticipate will form an additional black smoker to the three currently active at this site. In March 2004 we measured temperatures of 388° C in fluids from both the Bio9 and Bio9' smokers, putting them essentially on the two phase curve for seawater at this depth. For all of the Bio9 vents, as well as Tica, the fluids contain less than 300 mmoles/kg of Cl, approximately half the local seawater concentration. These high temperature and low Cl concentrations are accompanied by unusually low Si concentrations, <9.5 mmoles/kg. These data suggest a relatively shallow depth of reaction for the fluids, within a few hundred meters of the seafloor. These are the hottest temperatures measured in the Bio9 vents since the eruption in 1992. In contrast, the temperatures at P vent, about 60m south have cooled by ˜15° C since 2002. About 400m south, the chlorinity of the fluids from Ty and Io vents have increased, and Tube Worm Pillar, about 400m further south has become inactive. Therefore the changes in the vent fluids vary widely and often in opposite senses, over ˜1.5km of very hydrothermally active ridge. A more complete discussion of the changes and our interpretation of their implications for processes occurring subseafloor will be presented.

  15. Modeling mid-ocean ridge hydrothermal response to earthquakes, tides, and ocean currents: a case study at the Grotto mound, Endeavour Segment, Juan de Fuca Ridge

    NASA Astrophysics Data System (ADS)

    Xu, G.; Bemis, K. G.

    2014-12-01

    Seafloor hydrothermal systems feature intricate interconnections among oceanic, geological, hydrothermal, and biological processes. The advent of the NEPTUNE observatory operated by Ocean Networks Canada at the Endeavour Segment, Juan de Fuca Ridge enables scientists to study these interconnections through multidisciplinary, continuous, real-time observations. The multidisciplinary observatory instruments deployed at the Grotto Mound, a major study site of the NEPTUNE observatory, makes it a perfect place to study the response of a seafloor hydrothermal system to geological and oceanic processes. In this study, we use the multidisciplinary datasets recorded by the NEPTUNE Observatory instruments as observational tools to demonstrate two different aspects of the response of hydrothermal activity at the Grotto Mound to geological and oceanic processes. First, we investigate a recent increase in venting temperature and heat flux at Grotto observed by the Benthic and Resistivity Sensors (BARS) and the Cabled Observatory Vent Imaging Sonar (COVIS) respectively. This event started in Mar 2014 and is still evolving by the time of writing this abstract. An initial interpretation in light of the seismic data recorded by a neighboring ocean bottom seismometer on the NEPTUNE observatory suggests the temperature and heat flux increase is probably triggered by local seismic activities. Comparison of the observations with the results of a 1-D mathematical model simulation of hydrothermal sub-seafloor circulation elucidates the potential mechanisms underlying hydrothermal response to local earthquakes. Second, we observe significant tidal oscillations in the venting temperature time series recorded by BARS and the acoustic imaging of hydrothermal plumes by COVIS, which is evidence for hydrothermal response to ocean tides and currents. We interpret the tidal oscillations of venting temperature as a result of tidal loading on a poroelastic medium. We then invoke poroelastic theories to estimate the crustal permeability, a fundamental property of subsurface hydrothermal circulation, from the phase shift of the tidal oscillations of venting temperature relative to ambient ocean tides. These results together shed light on the influences of seismic and oceanic processes on a seafloor hydrothermal system.

  16. Hawaiian fissure fountains 1: decoding deposits-episode 1 of the 1969-1974 Mauna Ulu eruption

    USGS Publications Warehouse

    Parcheta, C.E.; Houghton, Bruce F.; Swanson, D.A.

    2012-01-01

    Deposits from episode 1 of the 1969–1974 Mauna Ulu eruption of Kīlauea provide an exceptional opportunity to study processes of low intensity Hawaiian fissure fountains. Episode 1 lava flows passed through dense forest that had little impact on flow dynamics; in contrast, the pattern of spatter preservation was strongly influenced by the forest (through the formation of tree molds) and the preexisting topography. A low, near-continuous spatter rampart is present upwind and upslope, on the north side of the fissure. Most of the pyroclastic products, however, fell downwind to the south of the fissure, but little was preserved due to two processes: (1) incorporation of proximal spatter in rheomorphic lava flows 10–20 m from the vents, and (2) the downslope transport of cooler spatter falling on top of these flows beyond 20 m from vent. The lava flow field itself shows a complex history. Initially, discharge from the fissure exceeded the transport capacity of the southern drainage pathways, and lava ponded dynamically to a maximum height of 4 m for 40–120 min, until fountains began to decline. During declining discharge, lava flowed both southward away from the fissure and increasingly back into the vents. There is a clear “lava-shed” or delineation between where lava drained northwards back into the fissure, and where it continued flowing to the south. The 1969 deposits suggest that care is needed when products of less well-documented eruptions are analyzed, as postdepositional transport of spatter may preclude the formation of classic paired (symmetrical) ramparts.

  17. 40 CFR 60.562-1 - Standards: Process emissions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Compound (VOC) Emissions from the Polymer Manufacturing Industry § 60.562-1 Standards: Process emissions... vent stream from a control device shall have car-sealed opened all valves in the vent system from the emission source to the control device and car-sealed closed all valves in vent system that would lead the...

  18. A hydrothermal seep on the Costa Rica margin: middle ground in a continuum of reducing ecosystems

    PubMed Central

    Levin, Lisa A.; Orphan, Victoria J.; Rouse, Greg W.; Rathburn, Anthony E.; Ussler, William; Cook, Geoffrey S.; Goffredi, Shana K.; Perez, Elena M.; Waren, Anders; Grupe, Benjamin M.; Chadwick, Grayson; Strickrott, Bruce

    2012-01-01

    Upon their initial discovery, hydrothermal vents and methane seeps were considered to be related but distinct ecosystems, with different distributions, geomorphology, temperatures, geochemical properties and mostly different species. However, subsequently discovered vents and seep systems have blurred this distinction. Here, we report on a composite, hydrothermal seep ecosystem at a subducting seamount on the convergent Costa Rica margin that represents an intermediate between vent and seep ecosystems. Diffuse flow of shimmering, warm fluids with high methane concentrations supports a mixture of microbes, animal species, assemblages and trophic pathways with vent and seep affinities. Their coexistence reinforces the continuity of reducing environments and exemplifies a setting conducive to interactive evolution of vent and seep biota. PMID:22398162

  19. 40 CFR Table 6 to Subpart Ppp of... - Process Vents From Continuous Unit Operations-Monitoring, Recordkeeping, and Reporting Requirements

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... operating—PR. d e Carbon Adsorber f Total regeneration stream mass or volumetric flow during carbon bed regeneration cycle(s), and 1. Record of total regeneration stream mass or volumetric flow for each carbon bed regeneration cycle.2. Record and report the total regeneration stream mass or volumetric flow during each...

  20. 40 CFR Table 6 to Subpart Ppp of... - Process Vents From Continuous Unit Operations-Monitoring, Recordkeeping, and Reporting Requirements

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... temperature established in the NCS or operating—PR. d,e Carbon Adsorber f Total regeneration stream mass or volumetric flow during carbon bed regeneration cycle(s), and 1. Record of total regeneration stream mass or volumetric flow for each carbon bed regeneration cycle.2. Record and report the total regeneration stream...

  1. 40 CFR Table 6 to Subpart Ppp of... - Process Vents From Continuous Unit Operations-Monitoring, Recordkeeping, and Reporting Requirements

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... temperature established in the NCS or operating—PR. d,e Carbon Adsorber f Total regeneration stream mass or volumetric flow during carbon bed regeneration cycle(s), and 1. Record of total regeneration stream mass or volumetric flow for each carbon bed regeneration cycle.2. Record and report the total regeneration stream...

  2. 40 CFR Table 6 to Subpart Ppp of... - Process Vents From Continuous Unit Operations-Monitoring, Recordkeeping, and Reporting Requirements

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... temperature established in the NCS or operating—PR. d,e Carbon Adsorber f Total regeneration stream mass or volumetric flow during carbon bed regeneration cycle(s), and 1. Record of total regeneration stream mass or volumetric flow for each carbon bed regeneration cycle.2. Record and report the total regeneration stream...

  3. 40 CFR Table 6 to Subpart Ppp of... - Process Vents From Continuous Unit Operations-Monitoring, Recordkeeping, and Reporting Requirements

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... operating—PR. d,e Carbon Adsorber f Total regeneration stream mass or volumetric flow during carbon bed regeneration cycle(s), and 1. Record of total regeneration stream mass or volumetric flow for each carbon bed regeneration cycle.2. Record and report the total regeneration stream mass or volumetric flow during each...

  4. 40 CFR Table 4 of Subpart Bbbbbbb... - Continuous Compliance Demonstration Methods With the Emission Reduction and PM Concentration...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... compliance by * * * 1. Requirement to route all process vent streams from equipment in target HAP service to a PM control device with a PM percent reduction efficiency of 95 percent (98 percent for new sources... chemical preparations operation was in target HAP service. The control device monitoring data are averaged...

  5. 40 CFR Table 4 of Subpart Bbbbbbb... - Continuous Compliance Demonstration Methods With the Emission Reduction and PM Concentration...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... compliance by * * * 1. Requirement to route all process vent streams from equipment in target HAP service to a PM control device with a PM percent reduction efficiency of 95 percent (98 percent for new sources... chemical preparations operation was in target HAP service. The control device monitoring data are averaged...

  6. 40 CFR Table 4 of Subpart Bbbbbbb... - Continuous Compliance Demonstration Methods With the Emission Reduction and PM Concentration...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... compliance by * * * 1. Requirement to route all process vent streams from equipment in target HAP service to a PM control device with a PM percent reduction efficiency of 95 percent (98 percent for new sources... chemical preparations operation was in target HAP service. The control device monitoring data are averaged...

  7. 40 CFR Table 4 of Subpart Bbbbbbb... - Continuous Compliance Demonstration Methods With the Emission Reduction and PM Concentration...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... compliance by * * * 1. Requirement to route all process vent streams from equipment in target HAP service to a PM control device with a PM percent reduction efficiency of 95 percent (98 percent for new sources... chemical preparations operation was in target HAP service. The control device monitoring data are averaged...

  8. Community Structure of Macrobiota and Environmental Parameters in Shallow Water Hydrothermal Vents off Kueishan Island, Taiwan

    PubMed Central

    Chan, Benny Kwok Kan; Wang, Teng-Wei; Chen, Pin-Chen; Lin, Chia-Wei; Chan, Tin-Yam; Tsang, Ling Ming

    2016-01-01

    Hydrothermal vents represent a unique habitat in the marine ecosystem characterized with high water temperature and toxic acidic chemistry. Vents are distributed at depths ranging from a few meters to several thousand meters. The biological communities of shallow-water vents have, however, been insufficiently studied in most biogeographic areas. We attempted to characterize the macrofauna and macroflora community inhabiting the shallow-water vents off Kueishan Island, Taiwan, to identify the main abiotic factors shaping the community structure and the species distribution. We determined that positively buoyant vent fluid exhibits a more pronounced negative impact to species on the surface water than on the bottom layer. Species richness increased with horizontal distance from the vent, and continuing for a distance of 2000 m, indicating that the vent fluid may exert a negative impact over several kilometers. The community structure off Kueishan Island displayed numerous transitions along the horizontal gradient, which were broadly congruent with changes in environmental conditions. Combination of variation in Ca2+, Cl-, temperature, pH and depth were revealed to show the strongest correlation with the change in benthic community structure, suggesting multiple factors of vent fluid were influencing the associated fauna. Only the vent crabs of Kueishan Island may have an obligated relationship with vents and inhabit the vent mouths because other fauna found nearby are opportunistic taxa that are more tolerant to acidic and toxic environments. PMID:26849440

  9. 46 CFR 56.50-85 - Tank-vent piping.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...-control systems or other, equivalent means, together with gauging devices and procedures for filling cargo... COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND APPURTENANCES Design Requirements Pertaining to Specific Systems § 56.50-85 Tank-vent piping. (a) This section...

  10. HYFLUX: Satellite Exploration of Natural Hydrocarbon Seeps and Discovery of a Methane Hydrate Mound at GC600

    NASA Astrophysics Data System (ADS)

    Garcia-Pineda, O. G.; MacDonald, I. R.; Shedd, W.; Zimmer, B.

    2009-12-01

    Analysis of natural hydrocarbon seeps is important to improve our understanding of methane flux from deeper sediments to the water column. In order to quantify natural hydrocarbon seep formations in the Northern Gulf of Mexico, a set of 686 Synthetic Aperture Radar (SAR) images was analyzed using the Texture Classifying Neural Network Algorithm (TCNNA), which processes SAR data to delineate oil slicks. This analysis resulted in a characterization of 396 natural seep sites distributed in the northern GOM. Within these sites, a maximum of 1248 individual vents where identified. Oil reaching the sea-surface is deflected from its source during transit through the water column. This presentation describes a method for estimating locations of active oil vents based on repeated slick detection in SAR. One of the most active seep formations was detected in MMS lease block GC600. A total of 82 SAR scenes (collected by RADARSAT-1 from 1995 to 2007) was processed covering this region. Using TCNNA the area covered by each slick was computed and Oil Slicks Origins (OSO) were selected as single points within detected oil slicks. At this site, oil slick signatures had lengths up to 74 km and up to 27 km^2 of area. Using SAR and TCNNA, four active vents were identified in this seep formation. The geostatistical mean centroid among all detections indicated a location along a ridge-line at ~1200m. Sea truth observations with an ROV, confirmed that the estimated location of vents had a maximum offset of ~30 m from their actual locations on the seafloor. At the largest vent, a 3-m high, 12-m long mound of oil-saturated gas hydrate was observed. The outcrop contained thousands of ice worms and numerous semi-rigid chimneys from where oily bubbles were escaping in a continuous stream. Three additional vents were found along the ridge; these had lower apparent flow, but were also plugged with gas hydrate mounds. These results support use of SAR data for precise delineation of active seep formation and shallow gas hydrate deposits.

  11. 33 CFR 159.61 - Vents.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Vents. 159.61 Section 159.61 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE... to minimize clogging by either the contents of the tank or climatic conditions such as snow or ice. ...

  12. 33 CFR 159.61 - Vents.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Vents. 159.61 Section 159.61 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE... to minimize clogging by either the contents of the tank or climatic conditions such as snow or ice. ...

  13. 33 CFR 159.61 - Vents.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Vents. 159.61 Section 159.61 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE... to minimize clogging by either the contents of the tank or climatic conditions such as snow or ice. ...

  14. 33 CFR 159.61 - Vents.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Vents. 159.61 Section 159.61 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE... to minimize clogging by either the contents of the tank or climatic conditions such as snow or ice. ...

  15. 46 CFR 153.1500 - Venting system rupture disks.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Venting system rupture disks. 153.1500 Section 153.1500 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Operations Maintenance § 153...

  16. 46 CFR 153.1500 - Venting system rupture disks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Venting system rupture disks. 153.1500 Section 153.1500 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Operations Maintenance § 153...

  17. 46 CFR 153.1500 - Venting system rupture disks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Venting system rupture disks. 153.1500 Section 153.1500 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Operations Maintenance § 153...

  18. 46 CFR 153.1500 - Venting system rupture disks.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Venting system rupture disks. 153.1500 Section 153.1500 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Operations Maintenance § 153...

  19. 46 CFR 153.1500 - Venting system rupture disks.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Venting system rupture disks. 153.1500 Section 153.1500 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Operations Maintenance § 153...

  20. Hydrothermal plumes along the East Pacific Rise, 8 deg 40 min to 11 deg 50 min N: Plume distribution and relationship to the apparent magmatic budget

    NASA Astrophysics Data System (ADS)

    Baker, E. T.; Feely, R. A.; Mottl, M. J.; Sansone, F. T.; Wheat, C. G.; Resing, J. A.; Lupton, J. E.

    1994-11-01

    The interactions between hydrothermal circulation and large-scale geological and geophysical characteristics of the mid-ocean ridge cannot be ascertained without large-scale views of the pattern of hydrothermal venting. Such multi-ridge-segment surveys of venting are accomplished most efficiently by mapping the distribution and intensity of hydrothermal plumes. In November 1991, we mapped hydrothermal temperature (Delta(theta)) and light attenuation (Delta(c)) anomalies above the East Pacific Rise (EPR) continuously from 8 deg 40 min to 11 deg 50 min N, a fast spreading ridge crest portion bisected by the Clipperton Transform Fault. Plume distributions show a precise correlation with the distribution of active vents where video coverage of the axial caldera is exhaustive. Elsewhere in the study area the sketchy knowledge of vent locations gleaned from scattered camera tows predicts only poorly the large-scale hydrothermal pattern revealed by our plume studies. Plumes were most intense between 9 deg 42 min and 9 deg 54 min N, directly over a March/April, 1991, seafloor eruption. These plumes had exceptionally high Delta(c)/Delta(theta) ratios compared to the rest of the study area; we suggest that the phase-separated gas-rich vent fluids discharging here fertilize an abundant population of bacteria. Hydrothermal plume distributions define three categories: intense and continuous, weak and discontinuous and negligible. The location of each category is virtually congruent with areas that are, respectively, magmatically robust, magmatically weak and magmatically starved, as inferred from previous measurements of axial bathymetric undulations, cross-axis inflation and magma chamber depth and continuity. This congruency implies a fine-scale spatial and temporal connection between magmatic fluctuations and hydrothermal venting. We thus speculate that, at least along this fast spreading section of the EPR, cyclic replenishment, eruption and freezing of the thin axial melt lens exerts greater control over hydrothermal venting than the more enduring zones of crystal mush and hot rock. We found intense, and continuous, plumes along 33% of the surveyed ridge crest, an observation implying that any point on the ridge is, on average, hyrothermally active one-third of the time. Combining this result with the 20% plume coverage found along the medium-rate Juan de Fuca Ridge suggests that superfast (approximately 150 mm/yr) spreading rates should support vigorous venting along approximately 50% of their length, if spreading rate and along-axis plume coverage are linearly related.

  1. Light in Thermal Environments (LITE) Workshop

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Light emitted from high temperature black smokers (350 C) at mid-ocean ridge spreading centers has been documented, but the source of this light and its photochemical and biological consequences have yet to be investigated. Preliminary studies indicate that thermal radiation alone might account for the 'glow' and that a novel photoreceptor in shrimp colonizing black smoker chimneys may detect this 'glow.' A more controversial question is whether there may be sufficient photon flux of appropriate wavelengths to support geothermally-driven photosynthesis (GDP) by microorganisms. Although only a very low level of visible and near infrared light may be emitted from any single hydrothermal vent, several aspects of the light make it of more than enigmatic interest. First, the light is clearly linked to geophysical (and perhaps geochemical) processes; its attributes may serve as powerful index parameters for monitoring change in these processes. Second, while the glow at a vent orifice is a very local phenomenon, more expansive subsurface environments may be illuminated, thereby increasing the spatial scale at which biological consequences of this light might be considered. Third, in contrast to intermittent bioluminescent light sources in the deep sea, the light emitted at vents almost certainly glows or flickers continuously over the life of the individual black smokers (years to decades); collectively, light emitted from black smokers along the ocean's spreading centers superimposed on background Cerenkov radiation negates the concept of the deep sea as an environment devoid of abiotic light. Finally, the history of hydrothermal activity predates the origin of life; light in the deep sea has been a continuous phenomenon on a geological time scale and may have served either as a seed or refugium for the evolution of biological photochemical reactions or adaptations.

  2. 46 CFR 98.25-70 - Venting.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Venting. 98.25-70 Section 98.25-70 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk § 98.25-70...

  3. 46 CFR 98.25-70 - Venting.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Venting. 98.25-70 Section 98.25-70 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk § 98.25-70...

  4. 46 CFR 98.25-70 - Venting.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Venting. 98.25-70 Section 98.25-70 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk § 98.25-70...

  5. 46 CFR 98.25-70 - Venting.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Venting. 98.25-70 Section 98.25-70 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk § 98.25-70...

  6. 46 CFR 98.25-70 - Venting.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Venting. 98.25-70 Section 98.25-70 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk § 98.25-70...

  7. 40 CFR 65.159 - Flare compliance determination and monitoring records.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... measurements, and exit velocity determinations made during the flare compliance determination; and (3) All... pilot flame is continuously present during the hour. For transfer racks, hourly records are required only while the transfer vent stream is being vented. (d) Compliance records. (1) Each owner or operator...

  8. 40 CFR 65.159 - Flare compliance determination and monitoring records.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... measurements, and exit velocity determinations made during the flare compliance determination; and (3) All... pilot flame is continuously present during the hour. For transfer racks, hourly records are required only while the transfer vent stream is being vented. (d) Compliance records. (1) Each owner or operator...

  9. 40 CFR 65.159 - Flare compliance determination and monitoring records.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... measurements, and exit velocity determinations made during the flare compliance determination; and (3) All... pilot flame is continuously present during the hour. For transfer racks, hourly records are required only while the transfer vent stream is being vented. (d) Compliance records. (1) Each owner or operator...

  10. 40 CFR 65.159 - Flare compliance determination and monitoring records.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... measurements, and exit velocity determinations made during the flare compliance determination; and (3) All... pilot flame is continuously present during the hour. For transfer racks, hourly records are required only while the transfer vent stream is being vented. (d) Compliance records. (1) Each owner or operator...

  11. 40 CFR 65.159 - Flare compliance determination and monitoring records.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... measurements, and exit velocity determinations made during the flare compliance determination; and (3) All... pilot flame is continuously present during the hour. For transfer racks, hourly records are required only while the transfer vent stream is being vented. (d) Compliance records. (1) Each owner or operator...

  12. Analytical and Experimental Study to Improve Computer Models for Mixing and Dilution of Soluble Hazardous Chemicals.

    DTIC Science & Technology

    1982-08-01

    Trajectory and Concentration of Various Plumes 59 IV.2 Tank and Cargo Geometry Assumed for Discharge Rate Calculation Using HACS Venting Rate Model 61...Discharge Rate Calculation Using HACS Venting Rate Model 62 IV.4 Original Test Plan for Validation of the Continuous Spill Model 66 IV.5 Final Test Plan...at t= 0. exEyEz = turbulent diffusivities. p = water density. Pc = chemical density. Symbols Used Only in Continuous-Spill Models for a Steady River b

  13. KSC-2009-2026

    NASA Image and Video Library

    2009-03-11

    CAPE CANAVERAL, Fla. – Seen in the photo is the hydrogen vent line attached to the Ground Umbilical Carrier Plate on space shuttle Discovery's external fuel tank. The shuttle is on Launch Pad 39A at NASA's Kennedy Space Center in Florida. A leak of hydrogen at the location during tanking caused the STS-119 mission to be scrubbed at 2:36 p.m. March 11. The vent line is at the intertank and is the overboard vent to the pad and the flare stack where the vented hydrogen is burned off. Mission management teams believe they have sufficient understanding of the repair plan to continue toward a March 15 launch at 7:43 p.m. EDT. Photo courtesy of United Space Alliance

  14. 40 CFR 265.1032 - Standards: Process vents.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... owner or operator of a fa-cil-ity with process vents associated with distillation, fractionation, thin-film evaporation, solvent extraction or -air or steam stripping operations man-aging haz-ard-ous wastes...

  15. 40 CFR 265.1032 - Standards: Process vents.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... owner or operator of a fa-cil-ity with process vents associated with distillation, fractionation, thin-film evaporation, solvent extraction or -air or steam stripping operations man-aging haz-ard-ous wastes...

  16. Continuous coal processing method

    NASA Technical Reports Server (NTRS)

    Ryason, P. R. (Inventor)

    1980-01-01

    A coal pump is provided in which solid coal is heated in the barrel of an extruder under pressure to a temperature at which the coal assumes plastic properties. The coal is continuously extruded, without static zones, using, for example, screw extrusion preferably without venting through a reduced diameter die to form a dispersed spray. As a result, the dispersed coal may be continuously injected into vessels or combustors at any pressure up to the maximum pressure developed in the extrusion device. The coal may be premixed with other materials such as desulfurization aids or reducible metal ores so that reactions occur, during or after conversion to its plastic state. Alternatively, the coal may be processed and caused to react after extrusion, through the die, with, for example, liquid oxidizers, whereby a coal reactor is provided.

  17. 40 CFR 63.7885 - What are the general standards I must meet for my affected process vents?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Remediation General Standards § 63.7885 What are the general standards I must meet for my affected process...) You determine for the remediation material treated or managed by the process vented through the...

  18. 49 CFR 179.300-13 - Venting, loading and unloading valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR TANK CARS Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW) § 179.300-13 Venting... (h)(3)(ii). Threads for the clean-out/inspection ports of DOT Specification 110A multi-unit tank car...

  19. Development of High Temperature (3400F) and High Pressure (27,000 PSI) Gas Venting Process for Nitrogen Batch Heater

    DTIC Science & Technology

    2018-01-01

    for Mach 14 possibly degrading seals ability to contain pressure due to exposure to high temperatures. A different solution for Mach 14 case will be...AEDC-TR-18-H-1 Development of High Temperature (3400°F) and High Pressure (27,000 PSI) Gas Venting Process for Nitrogen Batch...Development of High Temperature (3400°F) and High Pressure (27,000 PSI) Gas Venting Process for Nitrogen Batch Heater FA9101-10-D-0001-0010 5b. GRANT

  20. The 2013 eruption of Pavlof Volcano, Alaska: a spatter eruption at an ice- and snow-clad volcano

    USGS Publications Warehouse

    Waythomas, Christopher F.; Haney, Matthew M.; Fee, David; Schneider, David J.; Wech, Aaron G.

    2014-01-01

    The 2013 eruption of Pavlof Volcano, Alaska began on 13 May and ended 49 days later on 1 July. The eruption was characterized by persistent lava fountaining from a vent just north of the summit, intermittent strombolian explosions, and ash, gas, and aerosol plumes that reached as high as 8 km above sea level and on several occasions extended as much as 500 km downwind of the volcano. During the first several days of the eruption, accumulations of spatter near the vent periodically collapsed to form small pyroclastic avalanches that eroded and melted snow and ice to form lahars on the lower north flank of the volcano. Continued lava fountaining led to the production of agglutinate lava flows that extended to the base of the volcano, about 3–4 km beyond the vent. The generation of fountain-fed lava flows was a dominant process during the 2013 eruption; however, episodic collapse of spatter accumulations and formation of hot spatter-rich granular avalanches was a more efficient process for melting snow and ice and initiating lahars. The lahars and ash plumes generated during the eruption did not pose any serious hazards for the area. However, numerous local airline flights were cancelled or rerouted, and trace amounts of ash fall occurred at all of the local communities surrounding the volcano, including Cold Bay, Nelson Lagoon, Sand Point, and King Cove.

  1. KSC-2009-2027

    NASA Image and Video Library

    2009-03-11

    CAPE CANAVERAL, Fla. – A closeup of the 7-inch quick disconnect that will be replaced on the hydrogen vent line to the Ground Umbilical Carrier Plate of space shuttle Discovery's external fuel tank. The replacement will be made on Launch Pad 39A at NASA's Kennedy Space Center in Florida. A leak of hydrogen at the site during fueling caused the STS-119 mission to be scrubbed at 2:36 p.m. March 11. The vent line is at the intertank and is the overboard vent to the pad and the flare stack where the vented hydrogen is burned off. Mission management teams believe they have sufficient understanding of the repair plan to continue toward a March 15 launch at 7:43 p.m. EDT. Photo courtesy of United Space Alliance

  2. 40 CFR 63.107 - Identification of process vents subject to this subpart.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CATEGORIES National Emission Standards for Organic Hazardous Air Pollutants From the Synthetic Organic Chemical Manufacturing Industry § 63.107 Identification of process vents subject to this subpart. (a) The..., distillation unit, or reactor during operation of the chemical manufacturing process unit. (c) The discharge to...

  3. 40 CFR 63.107 - Identification of process vents subject to this subpart.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... CATEGORIES National Emission Standards for Organic Hazardous Air Pollutants From the Synthetic Organic Chemical Manufacturing Industry § 63.107 Identification of process vents subject to this subpart. (a) The..., distillation unit, or reactor during operation of the chemical manufacturing process unit. (c) The discharge to...

  4. 40 CFR 63.107 - Identification of process vents subject to this subpart.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... CATEGORIES National Emission Standards for Organic Hazardous Air Pollutants From the Synthetic Organic Chemical Manufacturing Industry § 63.107 Identification of process vents subject to this subpart. (a) The..., distillation unit, or reactor during operation of the chemical manufacturing process unit. (c) The discharge to...

  5. 40 CFR 63.491 - Batch front-end process vents-recordkeeping requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... CATEGORIES National Emission Standards for Hazardous Air Pollutant Emissions: Group I Polymers and Resins § 63.491 Batch front-end process vents—recordkeeping requirements. (a) Group determination records for...) through (a)(6) of this section for each batch front-end process vent subject to the group determination...

  6. 40 CFR 63.487 - Batch front-end process vents-reference control technology.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... control technology. 63.487 Section 63.487 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... CATEGORIES National Emission Standards for Hazardous Air Pollutant Emissions: Group I Polymers and Resins § 63.487 Batch front-end process vents—reference control technology. (a) Batch front-end process vents...

  7. 40 CFR 63.491 - Batch front-end process vents-recordkeeping requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... CATEGORIES National Emission Standards for Hazardous Air Pollutant Emissions: Group I Polymers and Resins § 63.491 Batch front-end process vents—recordkeeping requirements. (a) Group determination records for...) through (a)(6) of this section for each batch front-end process vent subject to the group determination...

  8. 40 CFR 63.491 - Batch front-end process vents-recordkeeping requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... CATEGORIES National Emission Standards for Hazardous Air Pollutant Emissions: Group I Polymers and Resins § 63.491 Batch front-end process vents—recordkeeping requirements. (a) Group determination records for...) through (a)(6) of this section for each batch front-end process vent subject to the group determination...

  9. 40 CFR 63.491 - Batch front-end process vents-recordkeeping requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CATEGORIES National Emission Standards for Hazardous Air Pollutant Emissions: Group I Polymers and Resins § 63.491 Batch front-end process vents—recordkeeping requirements. (a) Group determination records for...) through (a)(6) of this section for each batch front-end process vent subject to the group determination...

  10. Food-Web Complexity in Guaymas Basin Hydrothermal Vents and Cold Seeps.

    PubMed

    Portail, Marie; Olu, Karine; Dubois, Stanislas F; Escobar-Briones, Elva; Gelinas, Yves; Menot, Lénaick; Sarrazin, Jozée

    In the Guaymas Basin, the presence of cold seeps and hydrothermal vents in close proximity, similar sedimentary settings and comparable depths offers a unique opportunity to assess and compare the functioning of these deep-sea chemosynthetic ecosystems. The food webs of five seep and four vent assemblages were studied using stable carbon and nitrogen isotope analyses. Although the two ecosystems shared similar potential basal sources, their food webs differed: seeps relied predominantly on methanotrophy and thiotrophy via the Calvin-Benson-Bassham (CBB) cycle and vents on petroleum-derived organic matter and thiotrophy via the CBB and reductive tricarboxylic acid (rTCA) cycles. In contrast to symbiotic species, the heterotrophic fauna exhibited high trophic flexibility among assemblages, suggesting weak trophic links to the metabolic diversity of chemosynthetic primary producers. At both ecosystems, food webs did not appear to be organised through predator-prey links but rather through weak trophic relationships among co-occurring species. Examples of trophic or spatial niche differentiation highlighted the importance of species-sorting processes within chemosynthetic ecosystems. Variability in food web structure, addressed through Bayesian metrics, revealed consistent trends across ecosystems. Food-web complexity significantly decreased with increasing methane concentrations, a common proxy for the intensity of seep and vent fluid fluxes. Although high fluid-fluxes have the potential to enhance primary productivity, they generate environmental constraints that may limit microbial diversity, colonisation of consumers and the structuring role of competitive interactions, leading to an overall reduction of food-web complexity and an increase in trophic redundancy. Heterogeneity provided by foundation species was identified as an additional structuring factor. According to their biological activities, foundation species may have the potential to partly release the competitive pressure within communities of low fluid-flux habitats. Finally, ecosystem functioning in vents and seeps was highly similar despite environmental differences (e.g. physico-chemistry, dominant basal sources) suggesting that ecological niches are not specifically linked to the nature of fluids. This comparison of seep and vent functioning in the Guaymas basin thus provides further supports to the hypothesis of continuity among deep-sea chemosynthetic ecosystems.

  11. Food-Web Complexity in Guaymas Basin Hydrothermal Vents and Cold Seeps

    PubMed Central

    Olu, Karine; Dubois, Stanislas F.; Escobar-Briones, Elva; Gelinas, Yves; Menot, Lénaick; Sarrazin, Jozée

    2016-01-01

    In the Guaymas Basin, the presence of cold seeps and hydrothermal vents in close proximity, similar sedimentary settings and comparable depths offers a unique opportunity to assess and compare the functioning of these deep-sea chemosynthetic ecosystems. The food webs of five seep and four vent assemblages were studied using stable carbon and nitrogen isotope analyses. Although the two ecosystems shared similar potential basal sources, their food webs differed: seeps relied predominantly on methanotrophy and thiotrophy via the Calvin-Benson-Bassham (CBB) cycle and vents on petroleum-derived organic matter and thiotrophy via the CBB and reductive tricarboxylic acid (rTCA) cycles. In contrast to symbiotic species, the heterotrophic fauna exhibited high trophic flexibility among assemblages, suggesting weak trophic links to the metabolic diversity of chemosynthetic primary producers. At both ecosystems, food webs did not appear to be organised through predator-prey links but rather through weak trophic relationships among co-occurring species. Examples of trophic or spatial niche differentiation highlighted the importance of species-sorting processes within chemosynthetic ecosystems. Variability in food web structure, addressed through Bayesian metrics, revealed consistent trends across ecosystems. Food-web complexity significantly decreased with increasing methane concentrations, a common proxy for the intensity of seep and vent fluid fluxes. Although high fluid-fluxes have the potential to enhance primary productivity, they generate environmental constraints that may limit microbial diversity, colonisation of consumers and the structuring role of competitive interactions, leading to an overall reduction of food-web complexity and an increase in trophic redundancy. Heterogeneity provided by foundation species was identified as an additional structuring factor. According to their biological activities, foundation species may have the potential to partly release the competitive pressure within communities of low fluid-flux habitats. Finally, ecosystem functioning in vents and seeps was highly similar despite environmental differences (e.g. physico-chemistry, dominant basal sources) suggesting that ecological niches are not specifically linked to the nature of fluids. This comparison of seep and vent functioning in the Guaymas basin thus provides further supports to the hypothesis of continuity among deep-sea chemosynthetic ecosystems. PMID:27683216

  12. 46 CFR 151.50-76 - Hydrochloric acid, spent (NTE 15%).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... must provide for the free passage of air and gases to the vent or vents. (f) No lights may be used... 46 Shipping 5 2011-10-01 2011-10-01 false Hydrochloric acid, spent (NTE 15%). 151.50-76 Section 151.50-76 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS...

  13. 46 CFR 151.50-76 - Hydrochloric acid, spent (NTE 15%).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... must provide for the free passage of air and gases to the vent or vents. (f) No lights may be used... 46 Shipping 5 2012-10-01 2012-10-01 false Hydrochloric acid, spent (NTE 15%). 151.50-76 Section 151.50-76 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS...

  14. 46 CFR 151.50-76 - Hydrochloric acid, spent (NTE 15%).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... must provide for the free passage of air and gases to the vent or vents. (f) No lights may be used... 46 Shipping 5 2014-10-01 2014-10-01 false Hydrochloric acid, spent (NTE 15%). 151.50-76 Section 151.50-76 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS...

  15. 46 CFR 151.50-76 - Hydrochloric acid, spent (NTE 15%).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... must provide for the free passage of air and gases to the vent or vents. (f) No lights may be used... 46 Shipping 5 2013-10-01 2013-10-01 false Hydrochloric acid, spent (NTE 15%). 151.50-76 Section 151.50-76 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS...

  16. 40 CFR Table 8 to Subpart Eeee of... - Continuous Compliance With Emission Limits

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., items 1 through 6 a. Reduce total organic HAP (or, upon approval, TOC) emissions from the closed vent... organic HAP (or, upon approval, TOC) in the exhaust of combustion devices i. Performing CMS monitoring and... HAP (or, upon approval, TOC) emissions during the loading of organic liquids from the closed vent...

  17. Distal transport of dissolved hydrothermal iron in the deep South Pacific Ocean

    PubMed Central

    Fitzsimmons, Jessica N.; Boyle, Edward A.; Jenkins, William J.

    2014-01-01

    Until recently, hydrothermal vents were not considered to be an important source to the marine dissolved Fe (dFe) inventory because hydrothermal Fe was believed to precipitate quantitatively near the vent site. Based on recent abyssal dFe enrichments near hydrothermal vents, however, the leaky vent hypothesis [Toner BM, et al. (2012) Oceanography 25(1):209–212] argues that some hydrothermal Fe persists in the dissolved phase and contributes a significant flux of dFe to the global ocean. We show here the first, to our knowledge, dFe (<0.4 µm) measurements from the abyssal southeast and southwest Pacific Ocean, where dFe of 1.0–1.5 nmol/kg near 2,000 m depth (0.4–0.9 nmol/kg above typical deep-sea dFe concentrations) was determined to be hydrothermally derived based on its correlation with primordial 3He and dissolved Mn (dFe:3He of 0.9–2.7 × 106). Given the known sites of hydrothermal venting in these regions, this dFe must have been transported thousands of kilometers away from its vent site to reach our sampling stations. Additionally, changes in the size partitioning of the hydrothermal dFe between soluble (<0.02 µm) and colloidal (0.02–0.4 µm) phases with increasing distance from the vents indicate that dFe transformations continue to occur far from the vent source. This study confirms that although the southern East Pacific Rise only leaks 0.02–1% of total Fe vented into the abyssal Pacific, this dFe persists thousands of kilometers away from the vent source with sufficient magnitude that hydrothermal vents can have far-field effects on global dFe distributions and inventories (≥3% of global aerosol dFe input). PMID:25349389

  18. 40 CFR 65.85 - Procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... permit limit applicable to the process vent. (4) Design analysis based on accepted chemical engineering principles, measurable process parameters, or physical or chemical laws or properties. (5) All data... tested for vapor tightness. (b) Engineering assessment. Engineering assessment to determine if a vent...

  19. 40 CFR 65.85 - Procedures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... permit limit applicable to the process vent. (4) Design analysis based on accepted chemical engineering principles, measurable process parameters, or physical or chemical laws or properties. (5) All data... tested for vapor tightness. (b) Engineering assessment. Engineering assessment to determine if a vent...

  20. 40 CFR 65.85 - Procedures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... permit limit applicable to the process vent. (4) Design analysis based on accepted chemical engineering principles, measurable process parameters, or physical or chemical laws or properties. (5) All data... tested for vapor tightness. (b) Engineering assessment. Engineering assessment to determine if a vent...

  1. 40 CFR 65.85 - Procedures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... permit limit applicable to the process vent. (4) Design analysis based on accepted chemical engineering principles, measurable process parameters, or physical or chemical laws or properties. (5) All data... tested for vapor tightness. (b) Engineering assessment. Engineering assessment to determine if a vent...

  2. 40 CFR 65.85 - Procedures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... permit limit applicable to the process vent. (4) Design analysis based on accepted chemical engineering principles, measurable process parameters, or physical or chemical laws or properties. (5) All data... tested for vapor tightness. (b) Engineering assessment. Engineering assessment to determine if a vent...

  3. Characterization of On-Orbit U.S. Lab Condensate Vacuum Venting

    NASA Astrophysics Data System (ADS)

    Schmidl, W. D.; Alred, J. A.; Mikatarian, R.; Soares, C.; Miles, E.

    2002-01-01

    The venting of liquid streams into a vacuum has been studied extensively for many years. An experiment was performed aboard the International Space Station (ISS) to video tape the U.S. Lab's condensate venting event with cameras located on the Space Station Remote Manipulator System (SSRMS). Images of the vent plume were acquired close to both the port and starboard vent nozzles. The imaging started with a wider view and then zoomed in closer before the shutdown phase of the vent event occurred. The objective of this experiment was to extend our understanding of the properties of venting liquids into space. Data from the video images were analyzed to obtain the approximate cone angle encompassing the core of the vent plume. The condensate vent plume was characterized as having three phases, a startup phase, a nominal phase, and a shutdown phase. The startup phase consisted of the initial period when the vent first started and the liquid first entered the heated line. The nominal phase was the period when the majority of the liquid was vented. The shutdown phase occurs close to the end of the vent event. The shutdown phase was further divided into two parts, the shutdown initial phase, and a later shutdown sputtering phase. The shutdown initial phase occurs when gas becomes entrained in the condensate liquid being vented. The sputtering phase occurred after the vent valve was closed, and the liquid/ice in the line was removed by continuing to heat the line to bake it out. It was determined that the ice particles were ejected at higher angles, but lower velocities, during the startup and shutdown phases. The number and velocities of ice particles ejected outside of the core region, during the startup, initial shutdown and shutdown sputtering phases were determined. The core of liquid ejected during the startup and shutdown phases was contained within a half cone angle of less than 60 degrees. The startup phase took approximately 36 seconds, the shutdown initial phase took approximately 22 seconds, and the shutdown sputtering phase took approximately 32 seconds. Results from the experiment were correlated with the Boeing ISS vent plume model.

  4. Periodic venting of MABR lumen allows high removal rates and high gas-transfer efficiencies.

    PubMed

    Perez-Calleja, P; Aybar, M; Picioreanu, C; Esteban-Garcia, A L; Martin, K J; Nerenberg, R

    2017-09-15

    The membrane-aerated biofilm reactor (MABR) is a novel treatment technology that employs gas-supplying membranes to deliver oxygen directly to a biofilm growing on the membrane surface. When operated with closed-end membranes, the MABR provides 100-percent oxygen transfer efficiencies (OTE), resulting in significant energy savings. However, closed-end MABRs are more sensitive to back-diffusion of inert gases, such as nitrogen. Back-diffusion reduces the average oxygen transfer rates (OTR), consequently decreasing the average contaminant removal fluxes (J). We hypothesized that venting the membrane lumen periodically would increase the OTR and J. Using an experimental flow cell and mathematical modeling, we showed that back-diffusion gas profiles developed over relatively long timescales. Thus, very short ventings could re-establish uniform gas profiles for relatively long time periods. Using modeling, we systematically explored the effect of the venting interval (time between ventings). At moderate venting intervals, opening the membrane for 20 s every 30 min, the venting significantly increased the average OTR and J without substantially impacting the OTEs. When the interval was short enough, in this case shorter than 20 min, the OTR was actually higher than for continuous open-end operation. Our results show that periodic venting is a promising strategy to combine the advantages of open-end and closed end operation, maximizing both the OTR and OTE. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. 40 CFR 63.7928 - How do I demonstrate continuous compliance with the emissions limitations and work practice...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... devices? 63.7928 Section 63.7928 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Site Remediation Closed Vent Systems...

  6. 40 CFR 63.7928 - How do I demonstrate continuous compliance with the emissions limitations and work practice...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... devices? 63.7928 Section 63.7928 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Site Remediation Closed Vent Systems...

  7. 40 CFR 63.7928 - How do I demonstrate continuous compliance with the emissions limitations and work practice...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... devices? 63.7928 Section 63.7928 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Site Remediation Closed Vent Systems...

  8. Living with the Heat. Submarine Ring of Fire--Grades 5-6. Hydrothermal Vent Ecology.

    ERIC Educational Resources Information Center

    National Oceanic and Atmospheric Administration (DOC), Rockville, MD.

    This activity is designed to teach about hydrothermal vent ecology. Students are expected to describe how hydrothermal vents are formed and characterize the physical conditions at these sites, explain chemosynthesis and contrast this process with photosynthesis, identify autotrophic bacteria as the basis for food webs in hydrothermal vent…

  9. 40 CFR 63.1260 - Reporting requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... process vents as required in § 63.1257(d)(2)(ii). (6) Data and other information supporting the determination of annual average concentrations by process simulation as required in § 63.1257(e)(1)(ii). (7... must be performed while a process with a vent subject to § 63.1254(a)(3) will be operating. (g...

  10. Using Image Analysis to Explore Changes In Bacterial Mat Coverage at the Base of a Hydrothermal Vent within the Caldera of Axial Seamount

    NASA Astrophysics Data System (ADS)

    Knuth, F.; Crone, T. J.; Marburg, A.

    2017-12-01

    The Ocean Observatories Initiative's (OOI) Cabled Array is delivering real-time high-definition video data from an HD video camera (CAMHD), installed at the Mushroom hydrothermal vent in the ASHES hydrothermal vent field within the caldera of Axial Seamount, an active submarine volcano located approximately 450 kilometers off the coast of Washington at a depth of 1,542 m. Every three hours the camera pans, zooms and focuses in on nine distinct scenes of scientific interest across the vent, producing 14-minute-long videos during each run. This standardized video sampling routine enables scientists to programmatically analyze the content of the video using automated image analysis techniques. Each scene-specific time series dataset can service a wide range of scientific investigations, including the estimation of bacterial flux into the system by quantifying chemosynthetic bacterial clusters (floc) present in the water column, relating periodicity in hydrothermal vent fluid flow to earth tides, measuring vent chimney growth in response to changing hydrothermal fluid flow rates, or mapping the patterns of fauna colonization, distribution and composition across the vent over time. We are currently investigating the seventh scene in the sampling routine, focused on the bacterial mat covering the seafloor at the base of the vent. We quantify the change in bacterial mat coverage over time using image analysis techniques, and examine the relationship between mat coverage, fluid flow processes, episodic chimney collapse events, and other processes observed by Cabled Array instrumentation. This analysis is being conducted using cloud-enabled computer vision processing techniques, programmatic image analysis, and time-lapse video data collected over the course of the first CAMHD deployment, from November 2015 to July 2016.

  11. 40 CFR 63.110 - Applicability.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Vents, Storage Vessels, Transfer Operations, and Wastewater § 63.110 Applicability. (a) This subpart applies to all process vents, storage vessels, transfer racks, wastewater streams, and in-process..., subpart III, NNN, or RRR, as applicable. (e) Overlap with other regulations for wastewater. (1) After the...

  12. 40 CFR 63.110 - Applicability.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Vents, Storage Vessels, Transfer Operations, and Wastewater § 63.110 Applicability. (a) This subpart applies to all process vents, storage vessels, transfer racks, wastewater streams, and in-process..., subpart III, NNN, or RRR, as applicable. (e) Overlap with other regulations for wastewater. (1) After the...

  13. Low Gravity venting of Refrigerant 11

    NASA Technical Reports Server (NTRS)

    Labus, T. L.; Aydelott, J. C.; Lacovic, R. F.

    1972-01-01

    An experimental investigation was conducted in a five-second zero gravity facility to examine the effects of venting initially saturated Refrigerant 11 from a cylindrical container (15-cm diameter) under reduced gravitational conditions. The system Bond numbers studied were 0 (weightlessness), 9 and 63; the liquid exhibited a nearly zero-degree contact angle on the container surface. During the venting process, both liquid-vapor interface and liquid bulk vaporization occurred. The temperature of the liquid in the immediate vicinity of the liquid-vapor interface was found to decrease during venting, while the liquid bulk temperature remained constant. Qualitative observations of the effects of system acceleration, vent rate, and vapor volume presented. Quantitative information concerning the ullage pressure decay during low gravity venting is also included.

  14. 40 CFR 60.5411 - What additional requirements must I meet to determine initial compliance for my closed vent...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false What additional requirements must I meet to determine initial compliance for my closed vent systems routing materials from storage vessels and centrifugal compressor wet seal degassing systems? 60.5411 Section 60.5411 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)...

  15. 46 CFR 56.97-30 - Hydrostatic tests (modifies 137.4).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Hydrostatic tests (modifies 137.4). 56.97-30 Section 56.97-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND APPURTENANCES Pressure Tests § 56.97-30 Hydrostatic tests (modifies 137.4). (a) Provision of air vents at high points. Vents must be...

  16. Implications of historical eruptive-vent migration on the northeast rift zone of Mauna Loa Volcano, Hawaii

    NASA Astrophysics Data System (ADS)

    Lockwood, John P.

    1990-07-01

    Five times within the past 138 yr (1852, 1855-1856, 1880-1881, 1942, and 1984), lava flows from vents on the northeast rift zone of Mauna Loa Volcano have reached within a few kilometres of Hilo (the largest city on the Island of Hawaii). Most lavas erupted on this rift zone in historical time have traveled northeastward (toward Hilo), because their eruptive vents have been concentrated north of the rift zone's broad topographic axis. However, with few exceptions each successive historical eruption on the northeast rift zone has occurred farther southeast than the preceding one. Had the 1984 eruptive vents (the most southeasterly yet) opened less than 200 m farther southeast, the bulk of the 1984 lavas would have flowed away from Hilo. If this historical vent-migration pattern continues, the next eruption on the northeast rift zone could send lavas to the southeast, toward less populated areas. The historical Mauna Loa vent-migration patterns mimic the southeastern "younging" of the Hawaiian-Emperor volcanic chain and may be cryptically related to northwestward movement of the Pacific plate. Systematic temporal-spatial vent-migration patterns may characterize eruptive activity at other volcanoes with flank activity and should be considered as an aid to long-term prediction of eruption sites.

  17. 40 CFR 63.441 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... or live steam. Closed-vent system means a system that is not open to the atmosphere and is composed... emissions from individual process vents, stacks, open pieces of process equipment, equipment leaks... stock chests, and their associated vacuum pumps, filtrate tanks, foam breakers or tanks, and any other...

  18. 40 CFR 63.441 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... or live steam. Closed-vent system means a system that is not open to the atmosphere and is composed... emissions from individual process vents, stacks, open pieces of process equipment, equipment leaks... stock chests, and their associated vacuum pumps, filtrate tanks, foam breakers or tanks, and any other...

  19. Morphometric variability within the axial zone of the southern Juan de Fuca Ridge: Interpretation from Sea MARC II, Sea MARC I, and deep-sea photography

    USGS Publications Warehouse

    Kappel, Ellen S.; Normark, William R.

    1987-01-01

    The morphometric characteristics of the axial regions of oceanic spreading centers are determined by (1) the type of volcanic flows, (2) the relation between primary volcanic relief (on a scale of a few meters to tens of meters) and degree of sediment cover, and (3) the extent of surficial expression and timing of tectonic disruption of the young oceanic crust. Even within a single, continuous, linear spreading-ridge segment with relatively uniform axial valley dimensions over a distance of 50 or more kilometers, such as along the southern Juan de Fuca Ridge, the changes in morphometric characteristics along axis within the youngest crust indicate distinct variation in tectonic and volcanic activity over short distances within short time periods. An integrated analysis of Sea MARC I, Sea MARC II, and photographic data for the southernmost continuous segment of the Juan de Fuca Ridge shows that generalizations about tectonic and volcanic processes at spreading ridges must consider both the temporal scale of processes as well as the physical scales of observations if predictive models are to be successful. Comparison of the morphometric expression within the major hydrothermal vent area and the rest of the southernmost ridge segment suggests that the mapped distribution of hydrothermal vents may reflect the extent of survey effort rather than uniqueness of geologic setting.

  20. 40 CFR 63.7184 - What emission limitations, operating limits, and work practice standards must I meet?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Pollutants for Semiconductor Manufacturing Emission Standards § 63.7184 What emission limitations, operating... this section on and after the compliance dates specified in § 63.7183. (b) Process vents—organic HAP emissions. For each organic HAP process vent, other than process vents from storage tanks, you must limit...

  1. 40 CFR 63.7184 - What emission limitations, operating limits, and work practice standards must I meet?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Pollutants for Semiconductor Manufacturing Emission Standards § 63.7184 What emission limitations, operating... this section on and after the compliance dates specified in § 63.7183. (b) Process vents—organic HAP emissions. For each organic HAP process vent, other than process vents from storage tanks, you must limit...

  2. 40 CFR 63.441 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... flash steam from the digester or live steam. Closed-vent system means a system that is not open to the... this subpart, including emissions from individual process vents, stacks, open pieces of process... stock chests, and their associated vacuum pumps, filtrate tanks, foam breakers or tanks, and any other...

  3. 40 CFR 63.441 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... flash steam from the digester or live steam. Closed-vent system means a system that is not open to the... this subpart, including emissions from individual process vents, stacks, open pieces of process... stock chests, and their associated vacuum pumps, filtrate tanks, foam breakers or tanks, and any other...

  4. 40 CFR 63.441 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... flash steam from the digester or live steam. Closed-vent system means a system that is not open to the... this subpart, including emissions from individual process vents, stacks, open pieces of process... stock chests, and their associated vacuum pumps, filtrate tanks, foam breakers or tanks, and any other...

  5. The NOAA/PMEL Vents Program - 1983 to 2013: A History of Deep-Sea Volcanic and Hydrothermal Exploration and Research

    NASA Astrophysics Data System (ADS)

    Hammond, S. R.; Baker, E. T.; Embley, R. W.

    2015-12-01

    Inspiration for the Vents program arose from two serendipitous events: the discovery of seafloor spreading-center hydrothermal venting on the Galápagos Rift in 1977, and NOAA's deployment of the first US civilian research multibeam bathymetric sonar on the NOAA Ship Surveyor in 1979. Multibeam mapping in the NE Pacific revealed an unprecedented and revolutionary perspective of the Gorda and Juan de Fuca spreading centers, thus stimulating a successful exploration for volcanic and hydrothermal activity at numerous locations along both. After the 1986 discovery of the first "megaplume,", quickly recognized as the water column manifestation of a deep submarine volcanic eruption, the Vents program embarked on a multi-decadal effort to discover and understand local-, regional-, and, ultimately, global-scale physical, chemical, and biological ocean environmental impacts of submarine volcanism and hydrothermal venting. The Vents program made scores of scientific discoveries, many of which owed their success to the program's equally innovative and productive technological prowess. These discoveries were documented in hundreds of peer-reviewed papers by Vents researchers and their colleagues around the world. An emblematic success was the internationally recognized, first-ever detection, location, and study of an active deep volcanic eruption in 1993. To continue the Vents mission and further enhance its effectiveness in marine science and technology innovation, the program was reorganized in 2014 into two distinct, but closely linked, programs: Earth-Oceans Interactions and Acoustics. Both are currently engaged in expeditions and projects that maintain the Vents tradition of pioneering ocean exploration and research.

  6. 40 CFR 65.140 - Applicability.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... FEDERAL AIR RULE Closed Vent Systems, Control Devices, and Routing to a Fuel Gas System or a Process § 65..., shutdown, and malfunction provisions in § 65.6) apply to routing emissions to processes, fuel gas systems, closed vent systems, control devices, and recovery devices where another subpart expressly references the...

  7. 40 CFR 63.1254 - Standards: Process vents.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) National Emission Standards for Pharmaceuticals Production § 63.1254 Standards: Process vents. (a) Existing... weight; and (3) The production-indexed HAP consumption factor for the 12-month period in which the..., as calibrated on methane or the predominant HAP, of 20 ppmv or less, and an outlet concentration of...

  8. 40 CFR 63.1254 - Standards: Process vents.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Standards for Pharmaceuticals Production § 63.1254 Standards: Process vents. (a) Existing sources. For each... weight; and (3) The production-indexed HAP consumption factor for the 12-month period in which the..., as calibrated on methane or the predominant HAP, of 20 ppmv or less, and an outlet concentration of...

  9. 40 CFR 63.1254 - Standards: Process vents.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) National Emission Standards for Pharmaceuticals Production § 63.1254 Standards: Process vents. (a) Existing... weight; and (3) The production-indexed HAP consumption factor for the 12-month period in which the..., as calibrated on methane or the predominant HAP, of 20 ppmv or less, and an outlet concentration of...

  10. 40 CFR 63.1254 - Standards: Process vents.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Standards for Pharmaceuticals Production § 63.1254 Standards: Process vents. (a) Existing sources. For each... weight; and (3) The production-indexed HAP consumption factor for the 12-month period in which the..., as calibrated on methane or the predominant HAP, of 20 ppmv or less, and an outlet concentration of...

  11. 40 CFR 63.1254 - Standards: Process vents.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Standards for Pharmaceuticals Production § 63.1254 Standards: Process vents. (a) Existing sources. For each... weight; and (3) The production-indexed HAP consumption factor for the 12-month period in which the..., as calibrated on methane or the predominant HAP, of 20 ppmv or less, and an outlet concentration of...

  12. 40 CFR 63.7890 - What emissions limitations and work practice standards must I meet for process vents?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... total organic compounds (TOC) (minus methane and ethane) to a level below 1.4 kg/hr and 2.8 Mg/yr (3.0... process vents the emissions of TOC (minus methane and ethane) by 95 percent by weight or more. (c) For...

  13. 40 CFR 63.645 - Test methods and procedures for miscellaneous process vents.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... applicable to the process vent. (iv) Design analysis based on accepted chemical engineering principles..., dry standard cubic meters per minute, at a temperature of 20 °C. (g) Engineering assessment may be... the highest daily emission rate. (1) Engineering assessment includes, but is not limited to, the...

  14. 40 CFR 63.1428 - Process vent requirements for group determination of PMPUs using a nonepoxide organic HAP to make...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Hazardous Air Pollutant Emissions for Polyether Polyols Production § 63.1428 Process vent requirements for... make or modify a polyether polyol for a PMPU are less than 11,800 kg/yr, the owner or operator of that...

  15. 40 CFR 63.1425 - Process vent control requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Standards for Hazardous Air Pollutant Emissions for Polyether Polyols Production § 63.1425 Process vent... operators of all affected sources using epoxides in the production of polyether polyols are subject to the... (c) of this section only if epoxides are used in the production of polyether polyols and nonepoxide...

  16. 40 CFR 63.107 - Identification of process vents subject to this subpart.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... to this subpart. 63.107 Section 63.107 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... going to a fuel gas system as defined in § 63.101. (4) A gas stream exiting a control device used to... transfer operation vent subject to § 63.119 or § 63.126. (8) A vent from a waste management unit subject to...

  17. 40 CFR 63.2460 - What requirements must I meet for batch process vents?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    .... (ii) When you conduct a performance test or design evaluation for a non-flare control device used to... paragraphs (c)(9)(ii)(A) through (D) of this section. The design evaluation option for small control devices...) of this section. (b) Group status. If a process has batch process vents, as defined in § 63.2550, you...

  18. 40 CFR 63.2460 - What requirements must I meet for batch process vents?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    .... (ii) When you conduct a performance test or design evaluation for a non-flare control device used to... paragraphs (c)(9)(ii)(A) through (D) of this section. The design evaluation option for small control devices...) of this section. (b) Group status. If a process has batch process vents, as defined in § 63.2550, you...

  19. 40 CFR 63.2460 - What requirements must I meet for batch process vents?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... (ii) When you conduct a performance test or design evaluation for a non-flare control device used to... paragraphs (c)(9)(ii)(A) through (D) of this section. The design evaluation option for small control devices... (c) of this section. (b) Group status. If a process has batch process vents, as defined in § 63.2550...

  20. 40 CFR 63.2460 - What requirements must I meet for batch process vents?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    .... (ii) When you conduct a performance test or design evaluation for a non-flare control device used to... paragraphs (c)(9)(ii)(A) through (D) of this section. The design evaluation option for small control devices... (c) of this section. (b) Group status. If a process has batch process vents, as defined in § 63.2550...

  1. 40 CFR 63.2460 - What requirements must I meet for batch process vents?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    .... (ii) When you conduct a performance test or design evaluation for a non-flare control device used to... paragraphs (c)(9)(ii)(A) through (D) of this section. The design evaluation option for small control devices... (c) of this section. (b) Group status. If a process has batch process vents, as defined in § 63.2550...

  2. Advances in detection of diffuse seafloor venting using structured light imaging.

    NASA Astrophysics Data System (ADS)

    Smart, C.; Roman, C.; Carey, S.

    2016-12-01

    Systematic, remote detection and high resolution mapping of low temperature diffuse hydrothermal venting is inefficient and not currently tractable using traditional remotely operated vehicle (ROV) mounted sensors. Preliminary results for hydrothermal vent detection using a structured light laser sensor were presented in 2011 and published in 2013 (Smart) with continual advancements occurring in the interim. As the structured light laser passes over active venting, the projected laser line effectively blurs due to the associated turbulence and density anomalies in the vent fluid. The degree laser disturbance is captured by a camera collecting images of the laser line at 20 Hz. Advancements in the detection of the laser and fluid interaction have included extensive normalization of the collected laser data and the implementation of a support vector machine algorithm to develop a classification routine. The image data collected over a hydrothermal vent field is then labeled as seafloor, bacteria or a location of venting. The results can then be correlated with stereo images, bathymetry and backscatter data. This sensor is a component of an ROV mounted imaging suite which also includes stereo cameras and a multibeam sonar system. Originally developed for bathymetric mapping, the structured light laser sensor, and other imaging suite components, are capable of creating visual and bathymetric maps with centimeter level resolution. Surveys are completed in a standard mowing the lawn pattern completing a 30m x 30m survey with centimeter level resolution in under an hour. Resulting co-registered data includes, multibeam and structured light laser bathymetry and backscatter, stereo images and vent detection. This system allows for efficient exploration of areas with diffuse and small point source hydrothermal venting increasing the effectiveness of scientific sampling and observation. Recent vent detection results collected during the 2013-2015 E/V Nautilus seasons will be presented. Smart, C. J. and Roman, C. and Carey, S. N. (2013) Detection of diffuse seafloor venting using structured light imaging, Geochemistry, Geophysics, Geosystems, 14, 4743-4757

  3. Vent Processes and Deposits of a Hiatus in a Violent Eruption: Quilotoa Volcano, Ecuador

    NASA Astrophysics Data System (ADS)

    Best, J. A.; Bustillos, J.; Ort, M. H.; Cashman, K. V.; Mothes, P. A.; di Muro, A.; Rosi, M.

    2010-12-01

    The 800 BP eruption of Quilotoa volcano, Ecuador, produced two plinian eruptions separated by a short (days-weeks) hiatus. Units 1 and 3 (U1 and U3) of the eruption correspond to the first and second Plinian eruptions, respectively, and produced fallout and pyroclastic density currents. Unit 2 (U2) records processes during the hiatus and consists of three subunits: U2a, U2b, and U2c. 147 tephra samples of U1, U2, and U3 were collected from 25 sites from around the volcano. Thickness and grain-size features were described, with particular attention paid to U2, in order to characterize the processes that occurred during the eruptive hiatus. Grain-size and componentry analysis of a subset of these samples reveals a number of trends. The upper part of U1 is massive and normally graded at its top, 32-45 % dominantly vitric ash ≤ 3.0 φ, and likely represents the clearing of the air at the end of the first plinian eruption. U2a, present out to a maximum of 7 km from the vent, has a polymodal distribution with a large fraction of 4.0 φ and finer vitric material. Dune forms occur in this unit, which are interpreted to be the product of surges. The areal distribution of U2a is constrained by topography, whereas U2b is not. U2b is coarser overall with alternating fine- (2-3φ) and coarse- (1-2φ) grained layers. The beds, both coarse and fine, have a near-bimodal grain-size distribution and normal grading. U2b is interpreted as a fall deposit. The U2a/U2b contact is gradational in that 0-2 beds of U2b material occur within the uppermost U2a beds at proximal localities, indicating vent conditions for both briefly coexisted. U2c is a <2-cm-thick vitric ash bed with sparse dense juvenile vitric lapilli. These lapilli also occur in the overlying basal U3 fallout, which has a polymodal grain-size distribution. U2b is characteristically orange in color due to the dust that loosely covers the grains. Hydrothermal activity within the vent is likely the source of this staining, with the simultaneous milling of the weakened material producing the orange dust. We interpret the dense vitric lapilli ≥ -2.0 φ of U2c as being from an explosion through a lava dome, and thus they indicate that the eruption was continuous from U2c through U3. Our current hypothesis is that, as the U1 eruption ended, magma stalled deep in the conduit and degassed hot acidic gas that streamed through the material clogging the vent. This elutriated vitric material that eventually formed a cap on the system. As the U3 magma began its ascent, gas flux increased, leading to explosions that gradually removed the vitric cap and deposited the vitric U2a. Then, more continuous gas streaming led to the development of a pulsatory eruption column that carried hot crystals and vitric grains from the vent clog into a convecting column and eventual deposition as U2b fallout, which was then followed by the establishment of the U3 eruption column.

  4. Spatial and Alignment Analyses for a field of Small Volcanic Vents South of Pavonis Mons Mars

    NASA Technical Reports Server (NTRS)

    Bleacher, J. E.; Glaze, L. S.; Greeley, R.; Hauber, E.; Baloga, S. M.; Sakimoto, S. E. H.; Williams, D. A.; Glotch, T. D.

    2008-01-01

    The Tharsis province of Mars displays a variety of small volcanic vent (10s krn in diameter) morphologies. These features were identified in Mariner and Viking images [1-4], and Mars Orbiter Laser Altimeter (MOLA) data show them to be more abundant than originally observed [5,6]. Recent studies are classifying their diverse morphologies [7-9]. Building on this work, we are mapping the location of small volcanic vents (small-vents) in the Tharsis province using MOLA, Thermal Emission Imaging System, and High Resolution Stereo Camera data [10]. Here we report on a preliminary study of the spatial and alignment relationships between small-vents south of Pavonis Mons, as determined by nearest neighbor and two-point azimuth statistical analyses. Terrestrial monogenetic volcanic fields display four fundamental characteristics: 1) recurrence rates of eruptions,2 ) vent abundance, 3) vent distribution, and 4) tectonic relationships [11]. While understanding recurrence rates typically requires field measurements, insight into vent abundance, distribution, and tectonic relationships can be established by mapping of remotely sensed data, and subsequent application of spatial statistical studies [11,12], the goal of which is to link the distribution of vents to causal processes.

  5. Management of turbidity current venting in reservoirs under different bed slopes.

    PubMed

    Chamoun, Sabine; De Cesare, Giovanni; Schleiss, Anton J

    2017-12-15

    The lifetime and efficiency of dams is endangered by the process of sedimentation. To ensure the sustainable use of reservoirs, many sediment management techniques exist, among which venting of turbidity currents. Nevertheless, a number of practical questions remain unanswered due to a lack of systematic investigations. The present research introduces venting and evaluates its performance using an experimental model. In the latter, turbidity currents travel on a smooth bed towards the dam and venting is applied through a rectangular bottom outlet. The combined effect of outflow discharge and bed slopes on the sediment release efficiency of venting is studied based on different criteria. Several outflow discharges are tested using three different bed slopes (i.e., 0%, 2.4% and 5.0%). Steeper slopes yield higher venting efficiency. Additionally, the optimal outflow discharge leading to the largest venting efficiency with the lowest water loss increases when moving from the horizontal bed to the inclined positions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. 22. STEEL ARCH SEGMENT AND VENT IN OFFICE, ROOM 2351, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    22. STEEL ARCH SEGMENT AND VENT IN OFFICE, ROOM 2351, SECOND FLOOR, NORTH SIDE. - Hughes Aircraft Company, Processing & Electronics Building, 6775 Centinela Avenue, Los Angeles, Los Angeles County, CA

  7. 40 CFR 63.1426 - Process vent requirements for determining organic HAP concentration, control efficiency, and...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... National Emission Standards for Hazardous Air Pollutant Emissions for Polyether Polyols Production § 63... percent reduction may be measured as total epoxide, total organic HAP, or as TOC minus methane and ethane... TOC (minus methane and ethane) concentrations in all process vent streams and primary and secondary...

  8. 40 CFR 63.1426 - Process vent requirements for determining organic HAP concentration, control efficiency, and...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... National Emission Standards for Hazardous Air Pollutant Emissions for Polyether Polyols Production § 63... percent reduction may be measured as total epoxide, total organic HAP, or as TOC minus methane and ethane... TOC (minus methane and ethane) concentrations in all process vent streams and primary and secondary...

  9. 40 CFR 63.640 - Applicability and designation of affected source.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... reformer catalyst regeneration vents, and sulfur plant vents; and (5) Emission points routed to a fuel gas... required for refinery fuel gas systems or emission points routed to refinery fuel gas systems. (e) The... petroleum refining process unit that is subject to this subpart; (3) Units processing natural gas liquids...

  10. 40 CFR 63.640 - Applicability and designation of affected source.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... reformer catalyst regeneration vents, and sulfur plant vents; and (5) Emission points routed to a fuel gas... required for refinery fuel gas systems or emission points routed to refinery fuel gas systems. (e) The... petroleum refining process unit that is subject to this subpart; (3) Units processing natural gas liquids...

  11. 40 CFR 63.1103 - Source category-specific applicability, definitions, and requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... separation of raw materials and by-products from the stabilized polymer. Front end process vent means any... vent systems, control devices, recovery devices, and routing to a fuel gas system or a process), as... allow worker access; passage of material into or out of the enclosure by conveyor, vehicles, or other...

  12. 40 CFR 65.149 - Boilers and process heaters.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... stream is not introduced as or with the primary fuel, a temperature monitoring device in the fire box...-throughput transfer racks, as applicable, shall meet the requirements of this section. (2) The vent stream... thermal units per hour) or greater. (ii) A boiler or process heater into which the vent stream is...

  13. 40 CFR 63.7937 - How do I demonstrate initial compliance with the general standards?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... compliance with the general standards? 63.7937 Section 63.7937 Protection of Environment ENVIRONMENTAL... Remediation General Compliance Requirements § 63.7937 How do I demonstrate initial compliance with the general... remediation material treated or managed by the process vented through the affected process vents has an...

  14. 40 CFR 63.7937 - How do I demonstrate initial compliance with the general standards?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... compliance with the general standards? 63.7937 Section 63.7937 Protection of Environment ENVIRONMENTAL... Remediation General Compliance Requirements § 63.7937 How do I demonstrate initial compliance with the general... remediation material treated or managed by the process vented through the affected process vents has an...

  15. 40 CFR 63.7937 - How do I demonstrate initial compliance with the general standards?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... compliance with the general standards? 63.7937 Section 63.7937 Protection of Environment ENVIRONMENTAL... Remediation General Compliance Requirements § 63.7937 How do I demonstrate initial compliance with the general... remediation material treated or managed by the process vented through the affected process vents has an...

  16. 40 CFR 63.7937 - How do I demonstrate initial compliance with the general standards?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Remediation General Compliance Requirements § 63.7937 How do I demonstrate initial compliance with the general... remediation material treated or managed by the process vented through the affected process vents has an..., according to the procedures § 63.7943, and recorded the average VOHAP concentration of the remediation...

  17. Five 'Supercool' Icelandic Glaciers

    NASA Astrophysics Data System (ADS)

    Knudsen, O.; Roberts, M. J.; Roberts, M. J.; Tweed, F. S.; Russell, A. J.; Lawson, D. E.; Larson, G. J.; Evenson, E. B.; Bjornsson, H.

    2001-12-01

    Sediment entrainment by glaciohydraulic supercooling has recently been demonstrated as an effective process at Matanuska glacier, Alaska. Although subfreezing meltwater temperatures have been recorded at several Alaskan glaciers, the link between supercooling and sediment accretion remains confined to Matanuska. This study presents evidence of glaciohydraulic supercooling and associated basal ice formation from five Icelandic glaciers: Skeidarárjökull, Skaftafellsjökull, Kvíárjökull, Flaájökull, and Hoffellsjökull. These observations provide the best example to-date of glaciohydraulic supercooling and related sediment accretion outside Alaska. Fieldwork undertaken in March, July and August 2001 confirmed that giant terraces of frazil ice, diagnostic of the presence of supercooled water, are forming around subglacial artesian vents. Frazil flocs retrieved from these vents contained localised sandy nodules at ice crystal boundaries. During periods of high discharge, sediment-laden frazil flocs adhere to the inner walls of vents, and continue to trap suspended sediment. Bands of debris-rich frazil ice, representing former vents, are texturally similar to basal ice exposures at the glacier margins, implying a process-form relationship between glaciohydraulic freeze-on and basal ice formation. It is hypothesised that glaciohydraulic supercooling is generating thick sequences of basal ice. Observations also confirm that in situ melting of basal ice creates thick sedimentary sequences, as sediment structures present in the basal ice can be clearly traced into ice-marginal ridges. Glaciohydraulic supercooling is an effective sediment entrainment mechanism at Icelandic glaciers. Supercooling has the capacity to generate thick sequences of basal ice and the sediments present in basal ice can be preserved. These findings are incompatible with established theories of intraglacial sediment entrainment and basal ice formation; instead, they concur with, and extend, the current model of Matanuska-type glaciohydraulic supercooling. This work adds a new dimension to the understanding of debris entrainment in temperate glaciers.

  18. Infrasonic harmonic tremor and degassing bursts from Halema'uma'u Crater, Kilauea Volcano, Hawaii

    USGS Publications Warehouse

    Fee, David; Garcés, Milton; Patrick, Matt; Chouet, Bernard; Dawson, Phil; Swanson, Donald A.

    2010-01-01

    The formation, evolution, collapse, and subsequent resurrection of a vent within Halema'uma'u Crater, Kilauea Volcano, produced energetic and varied degassing signals recorded by a nearby infrasound array between 2008 and early 2009. After 25 years of quiescence, a vent-clearing explosive burst on 19 March 2008 produced a clear, complex acoustic signal. Near-continuous harmonic infrasonic tremor followed this burst until 4 December 2008, when a period of decreased degassing occurred. The tremor spectra suggest volume oscillation and reverberation of a shallow gas-filled cavity beneath the vent. The dominant tremor peak can be sustained through Helmholtz oscillations of the cavity, while the secondary tremor peak and overtones are interpreted assuming acoustic resonance. The dominant tremor frequency matches the oscillation frequency of the gas emanating from the vent observed by video. Tremor spectra and power are also correlated with cavity geometry and dynamics, with the cavity depth estimated at ~219 m and volume ~3 x 106 m3 in November 2008. Over 21 varied degassing bursts were observed with extended burst durations and frequency content consistent with a transient release of gas exciting the cavity into resonance. Correlation of infrasound with seismicity suggests an open system connecting the atmosphere to the seismic excitation process at depth. Numerous degassing bursts produced very long period (0.03-0.1 Hz) infrasound, the first recorded at Kilauea, indicative of long-duration atmospheric accelerations. Kilauea infrasound appears controlled by the exsolution of gas from the magma, and the interaction of this gas with the conduits and cavities confining it.

  19. Coupled fluid and solid evolution in analogue volcanic vents

    NASA Astrophysics Data System (ADS)

    Solovitz, Stephen A.; Ogden, Darcy E.; Kim, Dave (Dae-Wook); Kim, Sang Young

    2014-07-01

    Volcanic eruptions emit rock particulates and gases at high speed and pressure, which change the shape of the surrounding rock. Simplified analytical solutions, field studies, and numerical models suggest that this process plays an important role in the behavior and hazards associated with explosive volcanic eruptions. Here we present results from a newly developed laboratory-scale apparatus designed to study this coupled process. The experiments used compressed air jets expanding into the laboratory through fabricated rock analogue material, which evolves through time during the experiment. The compressed air was injected at approximately 2.5 times atmospheric pressure. We fabricated rock analogues from sand and steel powder samples with a three-dimensional printing process. We studied the fluid development using phase-locked particle image velocimetry, while simultaneously observing the solid development via a video camera. We found that the fluid response was much more rapid than that of the solid, permitting a quasi-steady approximation. In most cases, the solid vent flared out rapidly, increasing its diameter by 20 to 100%. After the initial expansion, the vent and flow field achieved a near-steady condition for a long duration. The new expanded vent shapes permitted lower vent exit pressures and larger jet radii. In one experiment, after an initial vent shape development and establishment of steady flow behavior, rock failure occurred a second time, resulting in a new exit diameter and new steady state. This second failure was not precipitated by changes in the nozzle flow condition, and it radically changed the downstream flow dynamics. This experiment suggests that the brittle nature of volcanic host rock enables sudden vent expansion in the middle of an eruption without requiring a change in the conduit flow.

  20. 40 CFR 63.7941 - How do I conduct a performance test, design evaluation, or other type of initial compliance...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... vent; Ei, Eo = Mass rate of total organic compounds (TOC) (minus methane and ethane) or total HAP, from... reduction for all affected process vents, percent Ei = Mass rate of TOC (minus methane and ethane) or total... uncontrolled vents, as calculated in this section, kilograms TOC per hour or kilograms HAP per hour; Eo = Mass...

  1. 40 CFR 63.1015 - Closed vent systems and control devices; or emissions routed to a fuel gas system or process.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Closed vent systems and control... this part, except as provided in § 63.1002(b). (2) Owners or operators of closed vent systems and... in subpart SS of this part, except as provided in § 63.1002(b). (3) Owners or operators routing...

  2. Cascadia Gas Vent Distribution and Challenges to Quantify Margin-Wide Methane Fluxes

    NASA Astrophysics Data System (ADS)

    Scherwath, M.; Riedel, M.; Roemer, M.; Veloso, M.; Heesemann, M.; Spence, G.

    2017-12-01

    Gas venting along the Cascadia Margin has been mapped over decades with ship sonar and in recent years with permanent seafloor installations utilizing the seafloor observatories NEPTUNE of Ocean Networks Canada and the Cabled Array of the Ocean Observatories Initiative. We show the distribution of over 1000 vents, most on the shallow shelf. For a third of the vents we have estimated methane flow rates, ranging from 0.05 to 69 L/min, and extrapolate these results to a margin-wide methane flow estaimate of around 4 Mt/yr (at surface pressure and temperature) and a flux estimate of 0.05 kg yr-1 m-2. However, these estimates are based on several assumptions, e.g. bubble sizes or data coverage, providing large uncertainties. With continued research expeditions and potential seafloor calibration experiments, these data can be refined and improved in future years.

  3. Improved thermodynamic modeling of the no-vent fill process and correlation with experimental data

    NASA Technical Reports Server (NTRS)

    Taylor, William J.; Chato, David J.

    1991-01-01

    The United States' plans to establish a permanent manned presence in space and to explore the Solar System created the need to efficiently handle large quantities of subcritical cryogenic fluids, particularly propellants such as liquid hydrogen and liquid oxygen, in low- to zero-gravity environments. One of the key technologies to be developed for fluid handling is the ability to transfer the cryogens between storage and spacecraft tanks. The no-vent fill method was identified as one way to perform this transfer. In order to understand how to apply this method, a model of the no-vent fill process is being developed and correlated with experimental data. The verified models then can be used to design and analyze configurations for tankage and subcritical fluid depots. The development of an improved macroscopic thermodynamic model is discussed of the no-vent fill process and the analytical results from the computer program implementation of the model are correlated with experimental results for two different test tanks.

  4. 40 CFR 63.1427 - Process vent requirements for processes using extended cookout as an epoxide emission reduction...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... epoxides, and that are using ECO as a control technique to reduce epoxide emissions in order to comply with... provisions of this section. The owner or operator that is using ECO in order to comply with the emission... used to further reduce the HAP emissions from a process vent already controlled by ECO, then the owner...

  5. Trace element bias in the use of CO2 vents as analogues for low pH environments: Implications for contamination levels in acidified oceans

    NASA Astrophysics Data System (ADS)

    Vizzini, S.; Di Leonardo, R.; Costa, V.; Tramati, C. D.; Luzzu, F.; Mazzola, A.

    2013-12-01

    Research into the effects of ocean acidification on marine ecosystems has increasingly focused on natural CO2 vents, although their intrinsic environmental complexity means observations from these areas may not relate exclusively to pH gradients. In order to assess trace element levels and distribution in the Levante Bay (Vulcano Island, NE Sicily, Italy) and its suitability for studying biological effects of pH decline, Ba, Fe and trace elements (As, Cd, Co, Cr, Cu, Hg, Mn, Mo, Ni, Pb, V and Zn) in sediment were analysed from 7 transects. Where present, Cymodocea nodosa leaves and epiphytes were also analysed. At the spatial scale of the bay, trace element concentrations in sediments and biota showed wide variability, possibly related to both input from fluid emissions and seawater physico-chemical variables (i.e. pH and Eh), which may considerably affect the solubility and bioavailability of potentially harmful trace elements. According to two pollution indices (MSPI: Marine Sediment Pollution Index and SQG-Q: Sediment Quality Guideline Quotient), the bay can be considered to be affected by low contamination with moderate potential for adverse biological effects, especially in the area between about 150 and 350 m from the primary vent, where localized detrimental effects on biota may occur. Generally, biological samples showed concentrations that were comparable with the lower values of seagrass ranges. The overall results of this study support the complex spatial dynamics of trace elements in the CO2 vent studied, which are constrained by both direct input from the vent and/or biogeochemical processes affecting element precipitation at the sediment-seawater interface. Consequently, great caution should be used when relating biological changes along pH gradients to the unifactorial effect of pH only, as interactions with concurrent, multiple stressors, including trace element enrichments, may occur. This finding has implications for the use of CO2 vents as analogues in ocean acidification research. They should be considered more appropriately as analogues for low pH environments with non-negligible trace element contamination which, in a scenario of continuous increase in anthropogenic pollution, may be very common.

  6. Fissure near Cerberus Fossae with Tectonic Morphologies

    NASA Image and Video Library

    2014-01-15

    The linearity of the volcanic vent shown in this image observed by NASA Mars Reconnaissance Orbiter, in conjunction with evidence of lava flow from the vent, suggests control by combined volcano-tectonic processes.

  7. Impact of vent pipe diameter on characteristics of waste degradation in semi-aerobic bioreactor landfill.

    PubMed

    Jiang, Guobin; Liu, Dan; Chen, Weiming; Ye, Zhicheng; Liu, Hong; Li, Qibin

    2017-10-01

    The evolution mechanism of a vent pipe diameter on a waste-stabilization process in semi-aerobic bioreactor landfills was analyzed from the organic-matter concentration, biodegradability, spectral characteristics of dissolved organic matter, correlations and principal-component analysis. Waste samples were collected at different distances from the vent pipe and from different landfill layers in semi-aerobic bioreactor landfills with different vent pipe diameters. An increase in vent pipe diameter favored waste degradation. Waste degradation in landfills can be promoted slightly when the vent pipe diameter increases from 25 to 50 mm. It could be promoted significantly when the vent pipe diameter was increased to 75 mm. The vent pipe diameter is important in waste degradation in the middle layer of landfills. The dissolved organic matter in the waste is composed mainly of long-wave humus (humin), short-wave humus (fulvic acid) and tryptophan. The humification levels of the waste that was located at the center of vent pipes with 25-, 50- and 75-mm diameters were 2.2682, 4.0520 and 7.6419 Raman units, respectively. The appropriate vent pipe diameter for semi-aerobic bioreactor landfills with an 800-mm diameter was 75 mm. The effect of different vent pipe diameters on the degree of waste stabilization is reflected by two main components. Component 1 is related mainly to the content of fulvic acid, biologically degradable material and organic matter. Component 2 is related mainly to the content of tryptophan and humin from the higher vascular plants.

  8. 40 CFR 63.8242 - What are the installation, operation, and maintenance requirements for my continuous monitoring...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Hazardous Air Pollutants: Mercury Emissions From Mercury Cell Chlor-Alkali Plants Continuous Compliance... each by-product hydrogen stream, end box ventilation system vent, and mercury thermal recovery unit...

  9. 40 CFR 63.8242 - What are the installation, operation, and maintenance requirements for my continuous monitoring...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Hazardous Air Pollutants: Mercury Emissions From Mercury Cell Chlor-Alkali Plants Continuous Compliance... each by-product hydrogen stream, end box ventilation system vent, and mercury thermal recovery unit...

  10. 40 CFR 63.8242 - What are the installation, operation, and maintenance requirements for my continuous monitoring...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Hazardous Air Pollutants: Mercury Emissions From Mercury Cell Chlor-Alkali Plants Continuous Compliance... each by-product hydrogen stream, end box ventilation system vent, and mercury thermal recovery unit...

  11. 40 CFR 63.8242 - What are the installation, operation, and maintenance requirements for my continuous monitoring...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Hazardous Air Pollutants: Mercury Emissions From Mercury Cell Chlor-Alkali Plants Continuous Compliance... each by-product hydrogen stream, end box ventilation system vent, and mercury thermal recovery unit...

  12. 40 CFR 63.8242 - What are the installation, operation, and maintenance requirements for my continuous monitoring...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Hazardous Air Pollutants: Mercury Emissions From Mercury Cell Chlor-Alkali Plants Continuous Compliance... each by-product hydrogen stream, end box ventilation system vent, and mercury thermal recovery unit...

  13. 40 CFR 63.7926 - How do I demonstrate initial compliance with the emission limitations and work practice standards...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... devices? 63.7926 Section 63.7926 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Site Remediation Closed Vent Systems...

  14. 40 CFR 63.7926 - How do I demonstrate initial compliance with the emission limitations and work practice standards...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...? 63.7926 Section 63.7926 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Site Remediation Closed Vent Systems...

  15. 40 CFR 63.7926 - How do I demonstrate initial compliance with the emission limitations and work practice standards...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... devices? 63.7926 Section 63.7926 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Site Remediation Closed Vent Systems...

  16. Tephra Sedimentation from a Short-term Wind-affected Volcanic Plume of the 8 October 2016 Aso Nakadake Eruption, Japan

    NASA Astrophysics Data System (ADS)

    Tsuji, T.; Nishizaka, N.; Onishi, K.

    2017-12-01

    Sedimentation processes during explosive volcanic eruptions can be constrained based on detailed analysis of grain-size variation of tephra deposits. Especially, an accurate description of the amount of fine particles has also significant implications for the assessment of specific tephra hazards. Grain size studies for single short-term eruption has advantage to contribute understanding the sedimentation processes because it is simple compared to long-lasting eruption. The 2016 Aso Nakadake eruption, Japan represents an ideal for the study of short-term eruptions thanks to an accurate investigation. Then, we investigate the grain size variation with distance from the vent and sedimentological features of the deposit to discuss the sedimentation processes of the tephra fragments. The eruption provided pyroclastic flow deposit and fallout tephra which distributed NE to ENE direction from the vent. The deposits between 4 and 20 km from vent consist of fine-coated lapilli to coarse ash, ash pellet and mud droplet in ascending degree. The samples are lapilli-bearing within 20 km from vent and those outside of 20 km mainly consist of ash particles. Detailed analyses of individual samples highlight a rapid decay of maximum and mean grain size for the deposit from proximal to distal. The decay trend of maximum grain-size is approximated by three segments of exponential curves with two breaks-in-slope at 10 and 40 km from vent. Most of the sampled deposits are characterized by bimodal grain-size distributions, with the modes of the coarse subpopulation decreasing with distance from vent and those of the fine subpopulation being mostly stable. The fine subpopulation has been interpreted as being mostly associated with size-selective sedimentation processes (e.g., particle aggregation) confirmed by the existence of fine-coated particles, ash pellet and mud droplet. As the fine-coated particles generally have a higher terminal velocity than the individual constituent particles, those could be related with the rapid decrease of maximum grain-size with distance from vent at proximal area. Further detail grain-size analyses and theoretical studies can be contributed to understand the effect of fine ash aggregation on sedimentation processes quantitatively.

  17. A quantitative look at the demise of a basaltic vent: The death of Kupaianaha, Kilauea Volcano, Hawai'i

    USGS Publications Warehouse

    Kauahikaua, J.; Mangan, M.; Heliker, C.; Mattox, T.

    1996-01-01

    The Kupaianaha vent, the source of the 48th episode of the 1983-to-present Pu'u 'O'o-Kupaianaha eruption, erupted nearly continuously from July 1986 until February 1992. This investigation documents the geophysical and geologic monitoring of the final 10 months of activity at the Kupaianaha vent. Detailed very low frequency (VLF) electromagnetic profiles across the single lava tube transporting lava from the vent were used to determine the cross-sectional area of the molten lava within the tube. Combined with measurements of lava velocity, these data provide an estimate of the lava output of Kupaianaha. In addition, lava temperatures (calculated from analysis of quenched glass) and bulk-rock chemistry were obtained for samples taken from the tube at the same site. The combined data set shows the lava flux from Kupaianaha vent declining linearly from 250000 m3/day in April 1991 to 54000 m3/day by November 1991. During that time surface breakouts of lava from weak points along the tube occurred progressively closer to the vent, consistent with declining efficiency in lava transport. There were no significant changes in lava temperature or in bulk MgO content during this period. Another eruptive episode (the 49th) began uprift of Kupaianaha on 8 November 1991 and erupted lava concurrently with Kupaianaha for 18 days. Lava flux from Kupaianaha decreased in response to this new episode, but the response was delayed by approximately 1 day. After 14 November 1991, lava velocities were no longer measurable in the tube because the lava stream beneath the skylight had crusted over; however, the VLF-derived electrical conductances documented the decreasing flux of molten lava through the tube. Kupaianaha remained active, but output continued to decrease until early February 1992 when the last active surface flows were seen. In November 1991 we used the linearly decreasing effusion rate to accurately predict the date for the death of the Kupaianaha vent. The linear nature of the decline in lava tube conductance and the delayed and slow response of the Waha'ula tube conductances to the 49th eruptive episode led us to speculate that (a) the Kupaianaha vent shut down because of a decrease in driving pressure and not because of a freeze-up of the vent, and (b) that Pu'u 'O'o, episode 49, and Kupaianaha were fed nearly vertically from a source deep within the rift zone.

  18. A quantitative look at the demise of a basaltic vent: the death of Kupaianaha, Kilauea Volcano, Hawai'i

    NASA Astrophysics Data System (ADS)

    Kauahikaua, J.; Mangan, M.; Heliker, C.; Mattox, T.

    1996-07-01

    The Kupaianaha vent, the source of the 48th episode of the 1983-to-present Pu'u 'O'o Kupaianaha eruption, erupted nearly continuously from July 1986 until February 1992. This investigation documents the geophysical and geologic monitoring of the final 10 months of activity at the Kupaianaha vent. Detailed very low frequency (VLF) electromagnetic profiles across the single lava tube transporting lava from the vent were used to determine the cross-sectional area of the molten lava within the tube. Combined with measurements of lava velocity, these data provide an estimate of the lava output of Kupaianaha. In addition, lava temperatures (calculated from analysis of quenched glass) and bulk-rock chemistry were obtained for samples taken from the tube at the same site. The combined data set shows the lava flux from Kupaianaha vent declining linearly from 250 000 m3/day in April 1991 to 54 000 m3/day by November 1991. During that time surface breakouts of lava from weak points along the tube occurred progressively closer to the vent, consistent with declining efficiency in lava transport. There were no significant changes in lava temperature or in bulk MgO content during this period. Another eruptive episode (the 49th) began uprift of Kupaianaha on 8 November 1991 and erupted lava concurrently with Kupaianaha for 18 days. Lava flux from Kupaianaha decreased in response to this new episode, but the response was delayed by approximately 1 day. After 14 November 1991, lava velocities were no longer measurable in the tube because the lava stream beneath the skylight had crusted over; however, the VLF-derived electrical conductances documented the decreasing flux of molten lava through the tube. Kupaianaha remained active, but output continued to decrease until early February 1992 when the last active surface flows were seen. In November 1991 we used the linearly decreasing effusion rate to accurately predict the date for the death of the Kupaianaha vent. The linear nature of the decline in lava tube conductance and the delayed and slow response of the Waha'ula tube conductances to the 49th eruptive episode led us to speculate that (a) the Kupaianaha vent shut down because of a decrease in driving pressure and not because of a freeze-up of the vent, and (b) that Pu'u 'O'o, episode 49, and Kupaianaha were fed nearly vertically from a source deep within the rift zone.

  19. 40 CFR 65.167 - Other reports.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... FEDERAL AIR RULE Closed Vent Systems, Control Devices, and Routing to a Fuel Gas System or a Process § 65... reporting and shall include a description of any changes made to the closed vent system. (b) Startup...

  20. 40 CFR 63.7188 - What are my monitoring installation, operation, and maintenance requirements?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Semiconductor Manufacturing Compliance Requirements § 63.7188 What are my monitoring installation, operation... emissions of your semiconductor process vent through a closed vent system to a control device, you must...

  1. 40 CFR 63.7188 - What are my monitoring installation, operation, and maintenance requirements?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Semiconductor Manufacturing Compliance Requirements § 63.7188 What are my monitoring installation, operation... emissions of your semiconductor process vent through a closed vent system to a control device, you must...

  2. Fluid Flow and Sound Generation at Hydrothermal Vent Fields

    DTIC Science & Technology

    1988-04-01

    Pacific Rise The first evidence of vent sound generation came from data collected near hydrothermal vents at 21 N on the EPR where an array of ocean...associated with hydrothermal centers, one at 21 N on the East Pacific Rise (EPR) (Reidesel et al., 1982) and one on the Juan de Fuca Ridge (Bibee and Jacobson... East Pacific Rise at 210 N : the volcanic, tectonic and hydrothermal processes at

  3. Thermodynamic modeling of the no-vent fill methodology for transferring cryogens in low gravity

    NASA Technical Reports Server (NTRS)

    Chato, David J.

    1988-01-01

    The filling of tanks with cryogens in the low-gravity environment of space poses many technical challenges. Chief among these is the inability to vent only vapor from the tank as the filling proceeds. As a potential solution to this problem, the NASA Lewis Research Center is researching a technique known as No-Vent Fill. This technology potentially has broad application. The focus is the fueling of space based Orbital Transfer Vehicles. The fundamental thermodynamics of the No-Vent Fill process to develop an analytical model of No-Vent Fill is described. The model is then used to conduct a parametric investigation of the key parameters: initial tank wall temperature, liquid-vapor interface heat transfer rate, liquid inflow rate, and inflowing liquid temperatures. Liquid inflowing temperature and the liquid-vapor interface heat transfer rate seem to be the most significant since they influence the entire fill process. The initial tank wall temperature must be sufficiently low to prevent a rapid pressure rise during the initial liquid flashing stage, but then becomes less significant.

  4. 40 CFR Table 2 to Subpart Ffff of... - Emission Limits and Work Practice Standards for Batch Process Vents

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Pollutants: Miscellaneous Organic Chemical Manufacturing Pt. 63, Subpt. FFFF, Table 2 Table 2 to Subpart FFFF... Group 1 batch process vents a. Reduce collective uncontrolled organic HAP emissions from the sum of all... a flare); or Not applicable. b. Reduce collective uncontrolled organic HAP emissions from the sum of...

  5. 40 CFR 63.136 - Process wastewater provisions-individual drain systems.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... requirements of § 63.148 and the control device shall be designed, operated, and inspected in accordance with... that receives or manages a Group 1 wastewater stream or a residual removed from a Group 1 wastewater... cover and if vented, route the vapors to a process or through a closed vent system to a control device...

  6. 40 CFR 63.117 - Process vent provisions-reporting and recordkeeping requirements for group and TRE determinations...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... and recordkeeping requirements for group and TRE determinations and performance tests. (a) Each owner or operator subject to the control provisions for Group 1 process vents in § 63.113(a) or the... recordkeeping requirements for group and TRE determinations and performance tests. 63.117 Section 63.117...

  7. 40 CFR 63.136 - Process wastewater provisions-individual drain systems.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... requirements of § 63.148 and the control device shall be designed, operated, and inspected in accordance with... that receives or manages a Group 1 wastewater stream or a residual removed from a Group 1 wastewater... cover and if vented, route the vapors to a process or through a closed vent system to a control device...

  8. 40 CFR 63.136 - Process wastewater provisions-individual drain systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... requirements of § 63.148 and the control device shall be designed, operated, and inspected in accordance with... that receives or manages a Group 1 wastewater stream or a residual removed from a Group 1 wastewater... cover and if vented, route the vapors to a process or through a closed vent system to a control device...

  9. 40 CFR 63.136 - Process wastewater provisions-individual drain systems.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... requirements of § 63.148 and the control device shall be designed, operated, and inspected in accordance with... that receives or manages a Group 1 wastewater stream or a residual removed from a Group 1 wastewater... cover and if vented, route the vapors to a process or through a closed vent system to a control device...

  10. 40 CFR 63.117 - Process vent provisions-reporting and recordkeeping requirements for group and TRE determinations...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... and recordkeeping requirements for group and TRE determinations and performance tests. (a) Each owner or operator subject to the control provisions for Group 1 process vents in § 63.113(a) or the... recordkeeping requirements for group and TRE determinations and performance tests. 63.117 Section 63.117...

  11. Geobiology of Marine Magnetotactic Bacteria

    DTIC Science & Technology

    2006-06-01

    acids (e.g. lactate, acetate, oxalate , succinate, fumarate, malate, and citrate) which are continually transported into the soil, in part due to the...microbial mats, and hydrothermal vent waters. J Environ Monit 3: 61-66. 177 Lyons TW (1997) Sulfur isotopic trends and pathways of iron sulfide formation in...case in sediments, microbial mats, and hydrothermal vent waters. J Environ Monit 3: 61-66. 200 O’Sullivan DW, Hanson Jr AK, Kester DR (1997) The

  12. 40 CFR 65.67 - Reporting provisions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., organic HAP or TOC concentration, and/or TRE index value required under § 65.63(f) and recorded under § 65... 2B process vent, the organic HAP or TOC concentration of the vent stream is recalculated according to...

  13. WTP Waste Feed Qualification: Hydrogen Generation Rate Measurement Apparatus Testing Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stone, M. E.; Newell, J. D.; Smith, T. E.

    The generation rate of hydrogen gas in the Hanford tank waste will be measured during the qualification of the staged tank waste for processing in the Hanford Tank Waste Treatment and Immobilization Plant. Based on a review of past practices in measurement of the hydrogen generation, an apparatus to perform this measurement has been designed and tested for use during waste feed qualification. The hydrogen generation rate measurement apparatus (HGRMA) described in this document utilized a 100 milliliter sample in a continuously-purged, continuously-stirred vessel, with measurement of hydrogen concentration in the vent gas. The vessel and lid had a combinedmore » 220 milliliters of headspace. The vent gas system included a small condenser to prevent excessive evaporative losses from the sample during the test, as well as a demister and filter to prevent particle migration from the sample to the gas chromatography system. The gas chromatograph was an on line automated instrument with a large-volume sample-injection system to allow measurement of very low hydrogen concentrations. This instrument automatically sampled the vent gas from the hydrogen generation rate measurement apparatus every five minutes and performed data regression in real time. The fabrication of the hydrogen generation rate measurement apparatus was in accordance with twenty three (23) design requirements documented in the conceptual design package, as well as seven (7) required developmental activities documented in the task plan associated with this work scope. The HGRMA was initially tested for proof of concept with physical simulants, and a remote demonstration of the system was performed in the Savannah River National Laboratory Shielded Cells Mockup Facility. Final verification testing was performed using non-radioactive simulants of the Hanford tank waste. Three different simulants were tested to bound the expected rheological properties expected during waste feed qualification testing. These simulants were tested at different temperatures using purge gas spiked with varying amounts of hydrogen to provide verification that the system could accurately measure the hydrogen in the vent gas at steady state.« less

  14. Vented Chill / No-Vent Fill of Cryogenic Propellant Tanks

    NASA Technical Reports Server (NTRS)

    Rhys, Noah O.; Foster, Lee W.; Martin, Adam K.; Stephens, Jonathan R.

    2016-01-01

    Architectures for extended duration missions often include an on-orbit replenishment of the space vehicle's cryogenic liquid propellants. Such a replenishment could be accomplished via a tank-to-tank transfer from a dedicated tanker or a more permanent propellant depot storage tank. Minimizing the propellant loss associated with transfer line and receiver propellant tank thermal conditioning is essential for mass savings. A new methodology for conducting tank-to-tank transfer while minimizing such losses has been demonstrated. Charge-Hold-Vent is the traditional methodology for conducting a tank-to-tank propellant transfer. A small amount of cryogenic liquid is introduced to chill the transfer line and propellant tank. As the propellant absorbs heat and undergoes a phase change, the tank internal pressure increases. The tank is then vented to relieve pressure prior to another charge of cryogenic liquid being introduced. This cycle is repeated until the transfer lines and tank are sufficiently chilled and the replenishment of the propellant tank is complete. This method suffers inefficiencies due to multiple chill and vent cycles within the transfer lines and associated feed system components. Additionally, this system requires precise measuring of cryogenic fluid delivery for each transfer, multiple valve cycling events, and other complexities associated with cycled operations. To minimize propellant loss and greatly simplify on-orbit operations, an alternate methodology has been designed and demonstrated. The Vented Chill / No Vent Fill method is a simpler, constant flow approach in which the propellant tank and transfer lines are only chilled once. The receiver tank is continuously vented as cryogenic liquid chills the transfer lines, tank mass and ullage space. Once chilled sufficiently, the receiver tank valve is closed and the tank is completely filled. Interestingly, the vent valve can be closed prior to receiver tank components reaching liquid saturation temperature. An incomplete fill results if insufficient energy is removed from the tank's thermal mass and ullage space. The key to successfully conducting the no vent fill is to assure that sufficient energy is removed from the system prior to closing the receiver tank vent valve. This paper will provide a description of the transfer methodology and test article, and will provide a discussion of test results.

  15. Modeling of zero gravity venting: Studies of two-phase heat transfer under reduced gravity

    NASA Technical Reports Server (NTRS)

    Merte, H., Jr.

    1986-01-01

    The objective is to predict the pressure response of a saturated liquid-vapor system when undergoing a venting or depressurization process in zero gravity at low vent rates. An experimental investigation of the venting of cylindrical containers partially filled with initially saturated liquids was previously conducted under zero-gravity conditions and compared with an analytical model which incorporated the effect of interfacial mass transfer on the ullage pressure response during venting. A new model is presented to improve the estimation of the interfacial mass transfer. Duhammel's superposition integral is incorporated to approximate the transient temperature response of the interface, treating the liquid as a semi-infinite solid with conduction heat transfer. Account is also taken of the condensation taking place within the bulk of a saturated vapor as isentropic expansion takes place. Computational results are presented for the venting of R-11 from a given vessel and initial state for five different venting rates over a period of three seconds, and compared to prior NASA experiments. An improvement in the prediction of the final pressure takes place, but is still considerably below the measurements.

  16. Vesiculation Processes During Transient and Sustained Explosive Activity at Halema'uma'u Crater, Kīlauea in 2008-2013.

    NASA Astrophysics Data System (ADS)

    Houghton, B. F.; Orr, T. R.; Taddeucci, J.; Carey, R.; Del Bello, E.; Scarlato, P.; Patrick, M. R.

    2015-12-01

    The 2008-2015 summit eruption within Halema'uma'u crater, Kilauea has been characterized by alternations of passive degassing with two styles of explosive activity, both frequently triggered by rock falls that perturb the free surface of magma in the vent. In the first, larger rock falls trigger second vesiculation of magma at depths up to 100 m below the free surface ejecting juvenile bomb and lapilli populations of very variable vesicularity. The second, the topic of this presentation, consists of intervals of minutes to tens-of-minutes duration of low fountaining activity often from multiple locations. Vents may migrate with time, first across the free surface to its margins, and then around the margins, in response to convection processes in the underlying melt. Analysis of short sequences of high-speed, high-resolution video footage shows that the sustained fountaining is maintained by not by a continuous discharge but rather by closely spaced bursting of two-to-five meter-wide bubbles. Bubbles accelerate through the free surface at velocities of 10 to 40 m/s disrupting the viscoelastic crust and forming large fall-back, lacework pyroclasts and smaller highly vesicular bombs and lapilli.

  17. 40 CFR 65.155 - Other control devices.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) CONSOLIDATED FEDERAL AIR RULE Closed Vent Systems, Control Devices, and Routing to a Fuel Gas System or a Process § 65.155 Other control devices. (a) Other control device equipment and operating requirements. (1... requirements specified in § 65.63(a)(2), or 40 CFR 60.562-1(a)(1)(i)(A) for process vents, or § 65.83(a)(1) for...

  18. 40 CFR 63.1426 - Process vent requirements for determining organic HAP concentration, control efficiency, and...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... percent reduction may be measured as total epoxide, total organic HAP, or as TOC minus methane and ethane... TOC (minus methane and ethane) concentrations in all process vent streams and primary and secondary... million by volume total epoxide or TOC limit in § 63.1425(b)(1)(ii) or (b)(2)(iii), the sampling site...

  19. 40 CFR 63.645 - Test methods and procedures for miscellaneous process vents.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... TOC emission rate, as specified under paragraph (f) of this section, the sampling site shall be after... process vent TOC mass flow rate is less than 33 kilograms per day for an existing source or less than 6.8... shall determine the TOC mass flow rate by the following procedures: (1) The sampling site shall be...

  20. Rocket Motor Microphone Investigation

    NASA Technical Reports Server (NTRS)

    Pilkey, Debbie; Herrera, Eric; Gee, Kent L.; Giraud, Jerom H.; Young, Devin J.

    2010-01-01

    At ATK's facility in Utah, large full-scale solid rocket motors are tested. The largest is a five-segment version of the reusable solid rocket motor, which is for use on the Ares I launch vehicle. As a continuous improvement project, ATK and BYU investigated the use of microphones on these static tests, the vibration and temperature to which the instruments are subjected, and in particular the use of vent tubes and the effects these vents have at low frequencies.

  1. Retrieving eruptive vent conditions from dynamical properties of unsteady volcanic plume using high-speed imagery and numerical simulations

    NASA Astrophysics Data System (ADS)

    Tournigand, Pierre-Yves; Taddeucci, Jacopo; José Peña Fernandez, Juan; Gaudin, Damien; Sesterhenn, Jörn; Scarlato, Piergiorgio; Del Bello, Elisabetta

    2016-04-01

    Vent conditions are key parameters controlling volcanic plume dynamics and the ensuing different hazards, such as human health issues, infrastructure damages, and air traffic disruption. Indeed, for a given magma and vent geometry, plume development and stability over time mainly depend on the mass eruption rate, function of the velocity and density of the eruptive mixture at the vent, where direct measurements are impossible. High-speed imaging of eruptive plumes and numerical jet simulations were here non-dimensionally coupled to retrieve eruptive vent conditions starting from measurable plume parameters. High-speed videos of unsteady, momentum-driven volcanic plumes (jets) from Strombolian to Vulcanian activity from three different volcanoes (Sakurajima, Japan, Stromboli, Italy, and Fuego, Guatemala) were recorded in the visible and the thermal spectral ranges by using an Optronis CR600x2 (1280x1024 pixels definition, 500 Hz frame rate) and a FLIR SC655 (640x480 pixels definition, 50 Hz frame rate) cameras. Atmospheric effects correction and pre-processing of the thermal videos were performed to increase measurement accuracy. Pre-processing consists of the extraction of the plume temperature gradient over time, combined with a temperature threshold in order to remove the image background. The velocity and the apparent surface temperature fields of the plumes, and their changes over timescales of tenths of seconds, were then measured by particle image velocimetry and thermal image analysis, respectively, of the pre-processed videos. The parameters thus obtained are representative of the outer plume surface, corresponding to its boundary shear layer at the interface with the atmosphere, and may significantly differ from conditions in the plume interior. To retrieve information on the interior of the plume, and possibly extrapolate it even at the eruptive vent level, video-derived plume parameters were non-dimensionally compared to the results of numerical simulations of momentum-driven gas jets impulsively released from a vent in a pressurized container. These simulations solve flow conditions globally, thus allowing one to set empirical relations between flow conditions in different parts of the jet, most notably the shear layer, the flow centerline, and at the vent. Applying these relations to the volcanic cases gives access to the evolution of velocity and temperature at the vent. From these, the speed of sound and flow Mach number can be obtained, which in turn can be used to estimate the pressure ratio between atmosphere and vent and finally, assuming some conduit geometry and mixture density, the total amount of erupted gas. Preliminary results suggest subsonic exit velocities of the eruptive mixture at the vent, and a plume centerline velocity that can be twice as fast as the one measured at the plume boundary.

  2. Mass intrusion beneath Kilauea Volcano, Hawaii, constraints from gravity and geodetic measurements (1975-2008)

    NASA Astrophysics Data System (ADS)

    Bagnardi, M.; Eggers, A.; Battaglia, M.; Poland, M.; Johnson, D.

    2008-12-01

    Since January 3 1983, Kilauea Volcano, Hawaii, has erupted almost continuously from vents on the volcano's east rift zone. On March 19, 2008, an explosion at Halema'uma'u Crater, within the summit caldera of Kilauea, marked the opening of a second eruptive vent on the volcano. The east rift vent at Pu'u'O'o and the summit vent at Halema'uma'u continue to be active as of August 2008, marking the longest interval in Kilauea's recorded history of eruptive activity on the volcano. Four gravity surveys with a network covering Kilauea's summit area have been performed during 1975-2003. We reoccupied this 45-station network in January and July 2008 with three portable LaCoste-Romberg gravimeters (G209, G615 and EG026) using a double-looping procedure. These two most recent gravity surveys span the onset of summit eruptive activity. The micro-gravity data set, combined with existing geodetic data from leveling, GPS, EDM, and InSAR, allow us to investigate and model the shallow magma system under the summit caldera to roughly constrain its shape, position, volume change and density, and better understand its long and short term evolution. We corrected for the effect of vertical deformation on gravity data (the so-called free-air effect) using uplift measurements from annual surveys performed by the USGS Hawaiian Volcano Observatory. Preliminary analysis of this record, which covers more than 30 years, indicates a persistent positive residual gravity anomaly located at the southeast margin of Halema'uma'u Crater, very close to the location of the new summit eruptive vent. This anomaly suggests a long term mass accumulation beneath the summit caldera.

  3. Geothermal Gases--Community Experiences, Perceptions, and Exposures in Northern California.

    PubMed

    Chiu, Cindy H; Lozier, Matthew J; Bayleyegn, Tesfaye; Tait, Karen; Barreau, Tracy; Copan, Lori; Roisman, Rachel; Jackson, Rebecca; Smorodinsky, Svetlana; Kreutzer, Richard A; Yip, Fuyuen; Wolkin, Amy

    2015-12-01

    Lake County, California, is in a high geothermal-activity area. Over the past 30 years, the city of Clearlake has reported health effects and building evacuations related to geothermal venting. Previous investigations in Clearlake revealed hydrogen sulfide at levels known to cause health effects and methane at levels that can cause explosion risks. The authors conducted an investigation in multiple cities and towns in Lake County to understand better the risk of geothermal venting to the community. They conducted household surveys and outdoor air sampling of hydrogen sulfide and methane and found community members were aware of geothermal venting and some expressed concerns. The authors did not, however, find hydrogen sulfide above the California Environmental Protection Agency air quality standard of 30 parts per billion over one hour or methane above explosive thresholds. The authors recommend improving risk communication, continuing to monitor geothermal gas effects on the community, and using community reports and complaints to monitor and document geothermal venting incidents.

  4. 40 CFR Table 3 to Subpart G of... - Process Vents-Monitoring, Recordkeeping, and Reporting Requirements for Complying With 98 Weight...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Air Pollutants Emissions or a Limit of 20 Parts Per Million by Volume 3 Table 3 to Subpart G of Part... Process Vents, Storage Vessels, Transfer Operations, and Wastewater Pt. 63, Subpt. G, Table 3 Table 3 to.... Recapture devices The appropriate monitoring device identified in table 4 when, in the table, the term...

  5. 40 CFR Table 3 to Subpart G of... - Process Vents-Monitoring, Recordkeeping, and Reporting Requirements for Complying With 98 Weight...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Air Pollutants Emissions or a Limit of 20 Parts Per Million by Volume 3 Table 3 to Subpart G of Part... Process Vents, Storage Vessels, Transfer Operations, and Wastewater Pt. 63, Subpt. G, Table 3 Table 3 to.... Recapture devices The appropriate monitoring device identified in table 4 when, in the table, the term...

  6. 40 CFR Table 3 to Subpart G of... - Process Vents-Monitoring, Recordkeeping, and Reporting Requirements for Complying With 98 Weight...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Hazardous Air Pollutants Emissions or a Limit of 20 Parts Per Million by Volume 3 Table 3 to Subpart G of... Process Vents, Storage Vessels, Transfer Operations, and Wastewater Pt. 63, Subpt. G, Table 3 Table 3 to.... Recapture devices The appropriate monitoring device identified in table 4 when, in the table, the term...

  7. 40 CFR Table 3 to Subpart G of... - Process Vents-Monitoring, Recordkeeping, and Reporting Requirements for Complying With 98 Weight...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Hazardous Air Pollutants Emissions or a Limit of 20 Parts Per Million by Volume 3 Table 3 to Subpart G of... Process Vents, Storage Vessels, Transfer Operations, and Wastewater Pt. 63, Subpt. G, Table 3 Table 3 to.... Recapture devices The appropriate monitoring device identified in table 4 when, in the table, the term...

  8. 40 CFR Table 3 to Subpart G of... - Process Vents-Monitoring, Recordkeeping, and Reporting Requirements for Complying With 98 Weight...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Hazardous Air Pollutants Emissions or a Limit of 20 Parts Per Million by Volume 3 Table 3 to Subpart G of... Process Vents, Storage Vessels, Transfer Operations, and Wastewater Pt. 63, Subpt. G, Table 3 Table 3 to.... Recapture devices The appropriate monitoring device identified in table 4 when, in the table, the term...

  9. 40 CFR 63.1034 - Closed vent systems and control devices; or emissions routed to a fuel gas system or process...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Closed vent systems and control devices; or emissions routed to a fuel gas system or process standards. 63.1034 Section 63.1034 Protection... stringent. The 20 parts per million by volume standard is not applicable to the provisions of § 63.1016. (ii...

  10. 40 CFR 63.1034 - Closed vent systems and control devices; or emissions routed to a fuel gas system or process...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 10 2011-07-01 2011-07-01 false Closed vent systems and control devices; or emissions routed to a fuel gas system or process standards. 63.1034 Section 63.1034 Protection... stringent. The 20 parts per million by volume standard is not applicable to the provisions of § 63.1016. (ii...

  11. Imaging a Hydrate-Related Cold Vent Offshore Vancouver Island From Deep-Towed Multichannel Seismic Data

    DTIC Science & Technology

    2009-02-20

    vent). 2500 2600 2700 Distance (m) 2800 2900 3000 1.791 Figure 11. Southeast-northwest seismic section, showing hydrate cap details from DTI 6. The...line DT16 Line DTI 6 continues as a long transit line extending to the north- west. The 1999 COAMS (Canadian Ocean Acoustic Measurement System) grid...inline IN26 is coincident with DTI 6 (Figure 1). A com- bination of the surface-towed seismic data and the deep-towed DTAGS data is needed to provide

  12. Temporal and spatial variation in temperature experienced by macrofauna at Main Endeavour hydrothermal vent field

    NASA Astrophysics Data System (ADS)

    Lee, Raymond W.; Robert, Katleen; Matabos, Marjolaine; Bates, Amanda E.; Juniper, S. Kim

    2015-12-01

    A significant focus of hydrothermal vent ecological studies has been to understand how species cope with various stressors through physiological tolerance and biochemical resistance. Yet, the environmental conditions experienced by vent species have not been well characterized. This objective requires continuous observations over time intervals that can capture environmental variability at scales that are relevant to animals. We used autonomous temperature logger arrays (four roughly parallel linear arrays of 12 loggers spaced every 10-12 cm) to study spatial and temporal variations in the thermal regime experienced by hydrothermal vent macrofauna at a diffuse flow vent. Hourly temperatures were recorded over eight months from 2010 to 2011 at Grotto vent in the Main Endeavour vent field on the Juan de Fuca Ridge, a focus area of the Ocean Networks Canada cabled observatory. The conspicuous animal assemblages in video footage contained Ridgeia piscesae tubeworms, gastropods (primarily Lepetodrilus fucensis), and polychaetes (polynoid scaleworms and the palm worm Paralvinella palmiformis). Two dimensional spatial gradients in temperature were generally stable over the deployment period. The average temperature recorded by all arrays, and in some individual loggers, revealed distinctive fluctuations in temperature that often corresponded with the tidal cycle. We postulate that this may be related to changes in bottom currents or fluctuations in vent discharge. A marked transient temperature increase lasting over a period of days was observed in April 2011. While the distributions and behavior of Juan de Fuca Ridge vent invertebrates may be partially constrained by environmental temperature and temperature tolerance, except for the one transient high-temperature event, observed fluid temperatures were generally similar to the thermal preferences for some species, and typically well below lethal temperatures for all species. Average temperatures of the four arrays ranged from 4.1 to 11.0 °C during the deployment, indicating that on an hourly timescale the temperature conditions in this tubeworm community were fairly moderate and stable. The generality of these findings and behavioral responses of vent organisms to predictable rhythmicity and non-periodic temperature shifts are areas for further investigation.

  13. Kīlauea summit eruption—Lava returns to Halemaʻumaʻu

    USGS Publications Warehouse

    Babb, Janet L.; Wessells, Stephen M.; Neal, Christina A.

    2017-10-06

    In March 2008, a new volcanic vent opened within Halemaʻumaʻu, a crater at the summit of Kīlauea Volcano in Hawaiʻi Volcanoes National Park on the Island of Hawaiʻi. This new vent is one of two ongoing eruptions on the volcano. The other is on Kīlauea’s East Rift Zone, where vents have been erupting nearly nonstop since 1983. The duration of these simultaneous summit and rift zone eruptions on Kīlauea is unmatched in at least 200 years.Since 2008, Kīlauea’s summit eruption has consisted of continuous degassing, occasional explosive events, and an active, circulating lava lake. Because of ongoing volcanic hazards associated with the summit vent, including the emission of high levels of sulfur dioxide gas and fragments of hot lava and rock explosively hurled onto the crater rim, the area around Halemaʻumaʻu remains closed to the public as of 2017.Through historical photos of past Halemaʻumaʻu eruptions and stunning 4K imagery of the current eruption, this 24-minute program tells the story of Kīlauea Volcano’s summit lava lake—now one of the two largest lava lakes in the world. It begins with a Hawaiian chant that expresses traditional observations of a bubbling lava lake and reflects the connections between science and culture that continue on Kīlauea today.The video briefly recounts the eruptive history of Halemaʻumaʻu and describes the formation and continued growth of the current summit vent and lava lake. It features USGS Hawaiian Volcano Observatory scientists sharing their insights on the summit eruption—how they monitor the lava lake, how and why the lake level rises and falls, why explosive events occur, the connection between Kīlauea’s ongoing summit and East Rift Zone eruptions, and the impacts of the summit eruption on the Island of Hawaiʻi and beyond. The video is also available at the following U.S. Geological Survey Multimedia Gallery link (video hosted on YouTube): Kīlauea summit eruption—Lava returns to Halemaʻumaʻu

  14. A Foamy Lava Lake at Kilauea Volcano, Hawai`i

    NASA Astrophysics Data System (ADS)

    Poland, M. P.; Carbone, D.

    2012-12-01

    Kilauea Volcano, in Hawai`i, is currently erupting from two locations simultaneously: along the east rift zone and at the summit. The east rift zone eruption began in 1983 and is characterized by lava effusion from the Pu`u `O`o and nearby vents, while the summit eruptive vent, which opened in 2008, persistently emits gas and small amounts of ash while hosting a lava lake. On March 5, 2011, a dike initiated from the east rift zone magma conduit and reached the surface, resulting in the 4.5-day-long Kamoamoa fissure eruption just uprift of Pu`u `O`o. The eruption was accompanied by summit deflation as magma withdrew from subsurface reservoirs to feed the fissure eruption. The level of the summit lava lake dropped as the summit deflated. A continuously recording gravimeter located at Kilauea's summit (about 150 m east of the center of the summit eruptive vent, 80 m above the vent rim, and about 140 m above the highest level reached by the lava lake) measured a gravity decrease of about 150 μGal during the lava level drop, after taking into account corrections for the solid Earth tide. The gravity signal is caused by a combination of three processes. First, subsidence of 15 cm due to summit deflation moved the gravimeter closer to the center of the Earth, resulting in a gravity increase. Second, mass removal from the subsurface magma reservoir at a depth of 1.4 km (based on a model from GPS and InSAR data) caused a gravity decrease. Third, the drop in the level of the lava lake, which reached a maximum of about 150 m, led to a gravity decrease. Assuming a simple point source of pressure change and a typical density for basaltic magma (2.3-2.7 g/cm3), the first two processes can only explain a small percent of the observed gravity decrease, which must therefore be mainly due to the drop in the level of the lava lake. We developed a numerical model of the summit eruptive vent that takes into account its complex geometry (as deduced from geological observations). Using the change in lava level over time (data courtesy of Matt Patrick), we estimated that a lava density of about 0.8 g/cm3 is required to fit the gravity time series. Gravity results, therefore, argue that the upper part of the vent is occupied by a low-density lava foam (in agreement with models of Kilauea's summit eruption from seismic, gas, and geologic data by Tim Orr and Matt Patrick) and provide the only means of quantifying the lava lake density.

  15. 40 CFR 65.143 - Closed vent systems.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... storage vessel, process vent, transfer rack, or equipment leaks. (1) Collection of emissions. Each closed... material from a storage vessel, transfer rack or equipment leaks. Inspection records shall be generated as... (B) Conduct annual visual inspections for visible, audible, or olfactory indications of leaks. (ii...

  16. 40 CFR 65.142 - Standards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... of this subpart apply to Group 2A process vents. (c) Transfer rack requirements. The owner or... route transfer rack emissions through a closed vent system to a flare shall meet the applicable... requirements referenced therein. No other provisions of this subpart apply to transfer rack emissions routed...

  17. 40 CFR 63.118 - Process vent provisions-periodic reporting and recordkeeping requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... device or other means to achieve and maintain a TRE index value greater than 1.0 but less than 4.0 as... subpart and who elects to demonstrate compliance with the TRE index value greater than 4.0 under § 63.113... § 63.115(e) of this subpart, is made that causes a Group 2 process vent with a TRE greater than 4.0 to...

  18. 40 CFR 63.118 - Process vent provisions-periodic reporting and recordkeeping requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... device or other means to achieve and maintain a TRE index value greater than 1.0 but less than 4.0 as... subpart and who elects to demonstrate compliance with the TRE index value greater than 4.0 under § 63.113... § 63.115(e) of this subpart, is made that causes a Group 2 process vent with a TRE greater than 4.0 to...

  19. Microdistribution of Faunal Assemblages at Deep-Sea Hydrothermal Vents in the Southern Ocean

    PubMed Central

    Marsh, Leigh; Copley, Jonathan T.; Huvenne, Veerle A. I.; Linse, Katrin; Reid, William D. K.; Rogers, Alex D.; Sweeting, Christopher J.; Tyler, Paul A.

    2012-01-01

    Chemosynthetic primary production by microbes supports abundant faunal assemblages at deep-sea hydrothermal vents, with zonation of invertebrate species typically occurring along physico-chemical gradients. Recently discovered vent fields on the East Scotia Ridge (ESR) in the Southern Ocean represent a new province of vent biogeography, but the spatial dynamics of their distinct fauna have yet to be elucidated. This study determines patterns of faunal zonation, species associations, and relationships between faunal microdistribution and hydrothermal activity in a vent field at a depth of 2,400 m on the ESR. Remotely operated vehicle (ROV) dives obtained high-definition imagery of three chimney structures with varying levels of hydrothermal activity, and a mosaic image of >250 m2 of seafloor co-registered with temperature measurements. Analysis of faunal microdistribution within the mosaiced seafloor reveals a consistent pattern of faunal zonation with increasing distance from vent sources and peak temperatures. Assemblages closest to vent sources are visibly dominated by a new species of anomuran crab, Kiwa n. sp. (abundance >700 individuals m−2), followed by a peltospiroid gastropod (>1,500 individuals m−2), eolepadid barnacle (>1,500 individuals m−2), and carnivorous actinostolid anemone (>30 individuals m−2). Peripheral fauna are not dominated by a single taxon, but include predatory and scavenger taxa such as stichasterid seastars, pycnogonids and octopus. Variation in faunal microdistribution on chimneys with differing levels of activity suggests a possible successional sequence for vent fauna in this new biogeographic province. An increase in δ34S values of primary consumers with distance from vent sources, and variation in their δ13C values also indicate possible zonation of nutritional modes of the vent fauna. By using ROV videography to obtain a high-resolution representation of a vent environment over a greater extent than previous studies, these results provide a baseline for determining temporal change and investigations of processes structuring faunal assemblages at Southern Ocean vents. PMID:23144754

  20. On the global distribution of hydrothermal vent fields: One decade later

    NASA Astrophysics Data System (ADS)

    Beaulieu, S. E.; Baker, E. T.; German, C. R.

    2012-12-01

    Since the last global compilation one decade ago, the known number of active submarine hydrothermal vent fields has almost doubled. At the end of 2009, a total of 518 active vent fields was catalogued, with about half (245) visually confirmed and others (273) inferred active at the seafloor. About half (52%) of these vent fields are at mid-ocean ridges (MORs), 25% at volcanic arcs, 21% at back-arc spreading centers (BASCs), and 2% at intra-plate volcanoes and other settings. One third are in high seas, and the nations with the most known active vent fields within EEZs are Tonga, USA, Japan, and New Zealand. The increase in known vent fields reflects a number of factors, including increased national and commercial interests in seafloor hydrothermal deposits as mineral resources. Here, we have comprehensively documented the percentage of strike length at MORs and BASCs that has been systematically explored for hydrothermal activity. As of the end of 2009, almost 30% of the ~60,000 km of MORs had been surveyed at least with spaced vertical profiles to detect hydrothermal plumes. A majority of the vents discovered at MORs in the past decade occurred at segments with < 60 mm/yr full spreading rate. Discoveries at ultra-slow MORs in the past decade included the deepest known vent (Beebe at Mid-Cayman Rise) and high-temperature black smoker vents (e.g., Dragon at SWIR and Loki's Castle at Mohns Ridge), and the highest temperature vent was measured at the slow-spreading S MAR (Turtle Pits). Using a previously published equation for the linear relationship between the number of active vent fields per 100 km strike length (F_s) vs. weighted-average full spreading rate (u_s), we predicted 676 vent fields remaining to be discovered at MORs. Even accounting for the lower F_s at slower spreading rates, almost half of the vents that are predicted remaining to be discovered at MORs are at ultra-slow to slow spreading rates (< 40 mm/yr) and about 1/3 at intermediate rates (40-80 mm/yr). MOR regions that are little explored tend to be at high latitudes, such as the ultra-slow to slow spreading Arctic MORs (e.g., Kolbeinsey and Mohns Ridges), the ultra-slow American-Antarctic Ridge, and the intermediate spreading Pacific-Antarctic Ridge. Although a greater percentage of the ~11,000 km of BASCs has been surveyed for hydrothermal activity, the discoveries at BASCs in the past decade were mainly at segments with intermediate to fast spreading rates. Using the same equation for F_s vs. u_s, we predicted 71 vent fields remaining to be discovered at BASCs, and most are likely to be found at ultra-slow and slow spreading segments (e.g., Andaman Basin, and central to northern Mariana Trough). With 2/3 of our overall predicted total vent fields at spreading ridges remaining to be discovered, we expect that the next decade of exploration will continue to yield new discoveries, leading to new insights into biogeography of vent fauna and the global impacts of fluxes of heat and materials from vents into our oceans.

  1. 40 CFR 63.116 - Process vent provisions-performance test methods and procedures to determine compliance.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... reduce the vent stream halogen atom mass emission rate to less than 0.45 kilogram per hour prior to a combustion control device in compliance with § 63.113(c)(2) of this subpart shall determine the halogen atom...

  2. 40 CFR 63.116 - Process vent provisions-performance test methods and procedures to determine compliance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... reduce the vent stream halogen atom mass emission rate to less than 0.45 kilogram per hour prior to a combustion control device in compliance with § 63.113(c)(2) of this subpart shall determine the halogen atom...

  3. 40 CFR 63.116 - Process vent provisions-performance test methods and procedures to determine compliance.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... reduce the vent stream halogen atom mass emission rate to less than 0.45 kilogram per hour prior to a combustion control device in compliance with § 63.113(c)(2) of this subpart shall determine the halogen atom...

  4. 40 CFR 63.116 - Process vent provisions-performance test methods and procedures to determine compliance.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... reduce the vent stream halogen atom mass emission rate to less than 0.45 kilogram per hour prior to a combustion control device in compliance with § 63.113(c)(2) of this subpart shall determine the halogen atom...

  5. 78 FR 69337 - Greenhouse Gas Reporting Program: Amendments and Confidentiality Determinations for Fluorinated...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-19

    ... Classification System NF 3 nitrogen trifluoride NODA notice of data availability NTTAA National Technology... Previously Produced Fluorinated GHGs and From Venting of Residual Fluorinated GHGs From Containers 7... emissions from production and transformation processes; emissions from venting of container heels and...

  6. A sheet metal forming simulation of automotive outer panels considering the behavior of air in die cavity

    NASA Astrophysics Data System (ADS)

    Choi, Kwang Yong; Kim, Yun Chang; Choi, Hee Kwan; Kang, Chul Ho; Kim, Heon Young

    2013-12-01

    During a sheet metal forming process of automotive outer panels, the air trapped between a blank sheet and a die tool can become highly compressed, ultimately influencing the blank deformation and the press force. To prevent this problem, vent holes are drilled into die tools and needs several tens to hundreds according to the model size. The design and the drilling of vent holes are based on expert's experience and try-out result and thus the process can be one of reasons increasing development cycle. Therefore the study on the size, the number, and the position of vent holes is demanded for reducing development cycle, but there is no simulation technology for analyzing forming defects, making numerical sheet metal forming process simulations that incorporate the fluid dynamics of air. This study presents a sheet metal forming simulation of automotive outer panels (a roof and a body side outer) that simultaneously simulates the behavior of air in a die cavity. Through CAE results, the effect of air behavior and vent holes to blank deformation was analyzed. For this study, the commercial software PAM-STAMP{trade mark, serif} and PAM-SAFE{trade mark, serif} was used.

  7. Microbial community structure of hydrothermal deposits from geochemically different vent fields along the Mid-Atlantic Ridge

    USGS Publications Warehouse

    Flores, Gilberto E.; Campbell, James H.; Kirshtein, Julie D.; Meneghin, Jennifer; Podar, Mircea; Steinberg, Joshua I.; Seewald, Jeffrey S.; Tivey, Margaret Kingston; Voytek, Mary A.; Yang, Zamin K.; Reysenbach, Anna-Louise

    2011-01-01

    To evaluate the effects of local fluid geochemistry on microbial communities associated with active hydrothermal vent deposits, we examined the archaeal and bacterial communities of 12 samples collected from two very different vent fields: the basalt-hosted Lucky Strike (37°17'N, 32°16.3'W, depth 1600-1750m) and the ultramafic-hosted Rainbow (36°13'N, 33°54.1'W, depth 2270-2330m) vent fields along the Mid-Atlantic Ridge (MAR). Using multiplexed barcoded pyrosequencing of the variable region 4 (V4) of the 16S rRNA genes, we show statistically significant differences between the archaeal and bacterial communities associated with the different vent fields. Quantitative polymerase chain reaction (qPCR) assays of the functional gene diagnostic for methanogenesis (mcrA), as well as geochemical modelling to predict pore fluid chemistries within the deposits, support the pyrosequencing observations. Collectively, these results show that the less reduced, hydrogen-poor fluids at Lucky Strike limit colonization by strict anaerobes such as methanogens, and allow for hyperthermophilic microaerophiles, like Aeropyrum. In contrast, the hydrogen-rich reducing vent fluids at the ultramafic-influenced Rainbow vent field support the prevalence of methanogens and other hydrogen-oxidizing thermophiles at this site. These results demonstrate that biogeographical patterns of hydrothermal vent microorganisms are shaped in part by large scale geological and geochemical processes.

  8. Basal sublimation and venting of the north seasonal cap of Mars

    NASA Astrophysics Data System (ADS)

    Piqueux, S.; Christensen, P. R.

    2007-12-01

    Spots, fans and dark polygonal patterns form during the spring on the southern seasonal cap of Mars as a consequence of 1) the basal sublimation of the translucent and impermeable slab of carbon dioxide and 2) the venting of the CO2 gas loaded with dust and sand size material scoured from the surface of the polar layered deposits. The dark polygons on the cap have a similar formation process as the spots but the dust and sand erupt from elongated vents rather than point sources. In the summer, spiders and etched polygons remain on the southern polar layered deposits. The spiders are shaped by the scouring action of confined CO2 gas flowing between the cap and the basement and converging toward point sources, whereas the etched polygons result form the forced migration of the CO2 gas over longer distances. Comparable observations during the spring near the north pole on the seasonal cap indicate that similar processes occur in both polar regions and that the venting model developed for the south seasonal cap also operates near the north pole. However, spider and etched polygonal features are extremely uncommon on the north substrate, indicating that the conditions for their formation (e.g. mechanical strength of the slab and the substrate, transparency of the seasonal cap) are not met. The continual erosion and re-sedimentation occurring at the surface of the polar layered deposits by the seasonal degassing is a major geomorphological agent shaping the polar regions. The polar layered deposits have been proposed to contain the stratigraphic record of climatic changes and catastrophic events of very high interest for future missions. Our observations suggest that both polar regions deposits may have been locally disrupted by the seasonal sub-ice gas flow and that the stratigraphic record may have been partially lost. The Phoenix landing site might have been affected in the past and the stratigraphic information associated with the original deposition of the polar material partially disrupted due to this surface reworking.

  9. Faunal composition and organic surface encrustations at hydrothermal vents on the southern Juan De Fuca Ridge

    NASA Astrophysics Data System (ADS)

    Tunnicliffe, Verena; Fontaine, A. R.

    1987-10-01

    Examination of a small collection of macroinvertebrates from three vents of the southern Juan de Fuca vent field reveals differences between the vents with respect to species composition, species habits, and microbial and metallic deposits on their surfaces. TWo apparently new vestimentiferan species were found, and for the first time the Juan de Fuca palm worm was observed to dwell on smokers. High acidity values recorded in this system may interfere with the process of shell calcification in an archaeogastropod snail. The surfaces of vestimentifer an tubes at two vents are heavily encrusted with microbial and metallic accumulations. Scanning electron microscope, transmission electron microscope, and energy dispersive X ray microanalysis observations show that iron-based crusts on orange tubes are built from accumulations of an Fe-rich particle of distinctive size and shape. Morphological evidence is presented for the microbial origin of Fe-rich particles. Zn-rich particles found on black tubes are not of microbial origin. We suggest that iron deposition on surfaces in the vent environment is initially biocatalytic but subsequent deposits may build by simple inorganic reactions.

  10. Extraordinary phase separation and segregation in vent fluids from the southern East Pacific Rise

    USGS Publications Warehouse

    Von Damm, Karen L.; Lilley, M.D.; Shanks, Wayne C.; Brockington, M.; Bray, A.M.; O'Grady, K. M.; Olson, E.; Graham, A.; Proskurowski, G.

    2003-01-01

    The discovery of Brandon vent on the southern East Pacific Rise is providing new insights into the controls on midocean ridge hydrothermal vent fluid chemistry. The physical conditions at the time ofsampling (287 bar and 405??C) place the Brandon fluids very close to the critical point of seawater (298 bar and 407??C). This permits in situ study of the effects of near criticalphenomena, which are interpreted to be the primary cause of enhanced transition metal transport in these fluids. Of the five orifices on Brandon sampled, three were venting fluids with less than seawater chlorinity, and two were venting fluids with greater than seawater chlorinity. The liquid phase orifices contain 1.6-1.9 times the chloride content of the vapors. Most other elements, excluding the gases, have this same ratio demonstrating the conservative nature of phase separation and the lack of subsequent water-rock interaction. The vapor and liquid phases vent at the same time from orifices within meters of each other on the Brandon structure. Variations in fluid compositions occur on a time scale of minutes. Our interpretation is that phase separation and segregation must be occurring 'real time' within the sulfide structure itself. Fluids from Brandon therefore provide an unique opportunity to understand in situ phase separation without the overprinting of continued water-rock interaction with the oceanic crust, as well as critical phenomena. ?? 2002 Elsevier Science B.V. All rights reserved.

  11. Investigating the role of small vent volcanism during the development of Tharsis Province, Mars

    NASA Astrophysics Data System (ADS)

    Richardson, J. A.; Bleacher, J. E.; Connor, C.; Connor, L.; Glaze, L. S.

    2014-12-01

    Clusters of tens to hundreds of small volcanic vents have recently been recognized as a major component of Tharsis Province volcanism. These volcanic fields are formed from distributed-style, possibly monogenetic, volcanism and are composed of low sloped edifices with diameters of tens of kilometers and heights of tens to hundreds of meters. We report a new catalog of these small volcanic vents, now available through the USGS Astrogeology Science Center. This catalog was created with the use of gridded topographic data from the Mars Orbiter Laser Altimeter (MOLA) and images from the Thermal Emission Imaging System (THEMIS) and the High Resolution Stereo Camera (HRSC). We are now investigating isolated clusters of distributed volcanism in Tharsis with this dataset. We hypothesize that these clusters are formed from significant magmatic events that played a large role in the development of Tharsis. Currently, the catalog contains 1075 unique volcanic vents in the Tharsis Province. With the catalog, potentially isolated volcano clusters are identified with vent density estimation. Vent intensity for clusters is found to be 1 vent per 1000 sq km or less. Crater retention rates for one such cluster, Syria Planum, indicates that these distributed volcanic systems might continue as long as 700 Ma, or that monogenetic volcanic systems overprint older systems. Using a modified basal outlining algorithm with MOLA gridded data, shield volumes are found to be between 1-20 cubic km. Current results show distributed-style volcanism occuring in Tharsis orders of magnitude more dispersed than analogous volcano clusers on Earth, while individual edifices are found to be an order of magnitude larger than volcanoes in Earth clusters. Proof of concept results are reported for three identified clusters: Arsia Mons Caldera, Syria Planum, and Southern Pavonis Mons.

  12. 75 FR 65032 - Notice of Lodging of Consent Decree

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-21

    ... absorber vent as a Group 2 process vent under the Hazardous Organic NESHAP regulations. For three years, Westlake will also implement an enhanced Leak Detection and Repair program to control emissions of...'s common control, and Westlake will not contest administratively or judicially a finding by the...

  13. 40 CFR 63.1259 - Recordkeeping requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... required by § 63.1253(f)(2) and the pressure relief vent setting and the leak detection records specified... human health or the environment than if the storage tanks and process vents were controlled according to... guidance that the Administrator makes available for use or any other technically sound information or...

  14. 40 CFR 65.163 - Other records.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) Detailed schematics, design specifications of the control device, and piping and instrumentation diagrams... FEDERAL AIR RULE Closed Vent Systems, Control Devices, and Routing to a Fuel Gas System or a Process § 65... bypass lines that could divert a vent stream away from the control device and to the atmosphere, the...

  15. 40 CFR 98.127 - Records that must be retained.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... destruction device, a facility may track dates and time periods that process vents by-pass the destruction... in your GHG Monitoring Plan. (g) Container heel records. If you vent residual fluorinated GHGs from containers, maintain the following records of the measurements and calculations used to estimate emissions of...

  16. 40 CFR 98.127 - Records that must be retained.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... destruction device, a facility may track dates and time periods that process vents by-pass the destruction... in your GHG Monitoring Plan. (g) Container heel records. If you vent residual fluorinated GHGs from containers, maintain the following records of the measurements and calculations used to estimate emissions of...

  17. 40 CFR 98.127 - Records that must be retained.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... destruction device, a facility may track dates and time periods that process vents by-pass the destruction... in your GHG Monitoring Plan. (g) Container heel records. If you vent residual fluorinated GHGs from containers, maintain the following records of the measurements and calculations used to estimate emissions of...

  18. 40 CFR 98.127 - Records that must be retained.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... destruction device, a facility may track dates and time periods that process vents by-pass the destruction... in your GHG Monitoring Plan. (g) Container heel records. If you vent residual fluorinated GHGs from containers, maintain the following records of the measurements and calculations used to estimate emissions of...

  19. 49 CFR 179.103-3 - Venting, loading and unloading valves, measuring and sampling devices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR TANK CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109... not less than one-fourth inch in thickness. (c) When tank car is used to transport liquefied flammable...

  20. 49 CFR 179.103-3 - Venting, loading and unloading valves, measuring and sampling devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR TANK CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109... not less than one-fourth inch in thickness. (c) When tank car is used to transport liquefied flammable...

  1. 49 CFR 179.103-3 - Venting, loading and unloading valves, measuring and sampling devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR TANK CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109... not less than one-fourth inch in thickness. (c) When tank car is used to transport liquefied flammable...

  2. The vent microbiome: patterns and drivers

    NASA Astrophysics Data System (ADS)

    Pachiadaki, M.

    2015-12-01

    Microbial processes within deep-sea hydrothermal vents affect the global biogeochemical cycles. Still, there are significant gaps in our understanding of the microbiology and the biogeochemistry of deep-sea hydrothermal systems. Vents differ in temperature, host rock composition and fluid chemistry; factors that are hypothesized to shape the distribution of the microbial communities, their metabolic capabilities and their activities. Using large-scale single cell genomics, we obtained insights into the genomic content of several linkages of a diffuse flow vent. The genomes show high metabolic versatility. Sulfur oxidation appears to be predominant but there is the potential of using a variety of e- donors and acceptors to obtain energy. To further assess the ecological importance of the vent auto- and heterotrophs, the global biogeography of the analyzed lineages will be investigated by fragment recruitment of metagenomes produced from the same site as well as other hydrothermal systems. Metatranscriptomic and metaproteomic data will be integrated to examine the expression of the predominant metabolic pathways and thus the main energy sources driving chemoautotrophic production. The comparative analysis of the key players and associated pathways among various vent sites that differ in physicochemical characteristics is anticipated to decipher the patterns and drivers of the global dispersion and the local diversification of the vent microbiome.

  3. 40 CFR 63.10400 - How do I demonstrate initial compliance?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CATEGORIES (CONTINUED) National Emission Standards for Hospital Ethylene Oxide Sterilizers Initial Compliance... submitting an Initial Notification of Compliance Status certifying that you are venting the ethylene oxide...

  4. SEAFLOOR MANIFESTATIONS OF GAS VENTING AND NEAR SEAFLOOR GAS HYDRATE OCCURRENCES

    NASA Astrophysics Data System (ADS)

    Paull, C. K.; Ussler, W.; Caress, D. W.; Thomas, H.; Lundsten, E.; Riedel, M.; Lapham, L.

    2009-12-01

    High-resolution multibeam bathymetry and chirp seismic profiles collected with an AUV complimented by ROV observations and sampling reveal the fine scale geomorphology and seafloor structures associated with gas venting and/or near subsurface gas hydrate accumulations along the Pacific North American continental margin. Sites from Santa Monica Basin, northern and southern Hydrate Ridge, Barkley Canyon, Bullseye Vent and three previously unexplored vent sites near Bullseye Vent have been recently investigated. The new AUV data allow the identification of features and seafloor textures that were previously undetected and reveal the impact of gas venting, gas hydrate development and related phenomena on the seafloor morphology. Distinct geomorphic characteristics are interpreted to represent different stages in the development and evolution of the seafloor in these areas. The more mature features include distinct (>10 m high) elevated features (e.g., Santa Monica Mounds and the Hydrate Ridge Pinnacle), widespread areas where methane-derived carbonates are exposed on the surrounding seafloor (e.g., both Hydrate Ridge sites, and an unnamed ridge north of Bullseye Vent), circular seafloor craters with diameters of 3 to 50 m that appear to be associated with missing sections of the original seafloor (e.g., Bullseye Vent, northern Hydrate Ridge, and an unnamed ridge north of Bullseye Vent). Smaller mound-like features (<10 m in diameter and 1-3 m higher than the surrounding seafloor occur at Barkley Canyon and a newly explored vent system called Spinnaker Vent 6 km NW of Bullseye vent. Solid lens of gas hydrate are occasionally exposed along fractures on the sides of these mounds and suggest that these are push-up features associated with gas hydrate growth within the near seafloor sediments. The existence of both extensive methane-derived carbonates and chemosynthetic biological communities characterized by Vesicomya clams and Lamellibrachia tubeworms (which are slow growing) indicate that methane venting has occurred for protracted periods of time at these sites. However, the youngest appearing features occur in a gulch ~1 km NE of Bullseye Vent. They are associated with more-subtle (2-3 m in diameter and ~0.5 m high) seafloor mounds, with their crests crossed with small cracks lined with white bacterial mats, lack exposed methane-derived carbonates, Vesicomya clams or Lamellibrachia tubeworms. ROV-collected vibracores (<1.5 cm long) obtained from these subtle mounds characteristically encountered a hard layer at 30-60 cm sub-bottom. Where this layer was penetrated, methane bubbles would spontaneously gush out the hole and continue to flow out for more than an hour. These observations suggest that these small mounds are young features which have considerable volumes of over-pressured gas trapped near the seafloor. Together these observations reveal the integrated effect that gas and/or gas hydrate occurrences can have on the seafloor. The existence of apparently over-pressured gas within ~1 m of the seafloor has intriguing implications as to the geo-hazard potential of such sites.

  5. 46 CFR 154.519 - Piping relief valves.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Process Piping Systems § 154.519 Piping relief valves. (a) The liquid relief valve that protects the cargo piping system from liquid pressure exceeding the design pressure must discharge into: (1) A cargo tank; or (2) A cargo vent mast if that vent mast has a means for the detection and removal of the liquid...

  6. 46 CFR 154.519 - Piping relief valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Process Piping Systems § 154.519 Piping relief valves. (a) The liquid relief valve that protects the cargo piping system from liquid pressure exceeding the design pressure must discharge into: (1) A cargo tank; or (2) A cargo vent mast if that vent mast has a means for the detection and removal of the liquid...

  7. 46 CFR 154.519 - Piping relief valves.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Process Piping Systems § 154.519 Piping relief valves. (a) The liquid relief valve that protects the cargo piping system from liquid pressure exceeding the design pressure must discharge into: (1) A cargo tank; or (2) A cargo vent mast if that vent mast has a means for the detection and removal of the liquid...

  8. 46 CFR 154.519 - Piping relief valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Process Piping Systems § 154.519 Piping relief valves. (a) The liquid relief valve that protects the cargo piping system from liquid pressure exceeding the design pressure must discharge into: (1) A cargo tank; or (2) A cargo vent mast if that vent mast has a means for the detection and removal of the liquid...

  9. Ash production and dispersal from sustained low-intensity Mono-Inyo eruptions

    NASA Astrophysics Data System (ADS)

    Black, Benjamin A.; Manga, Michael; Andrews, Benjamin

    2016-08-01

    Recent rhyolitic volcanism has demonstrated that prolonged low-intensity ash venting may accompany effusive dome formation. We examine the possibility and some consequences of episodes of extended, weak ash venting at the rhyolitic Mono-Inyo chain in Eastern California. We describe ash-filled cracks within one of the youngest domes, Panum Crater, which provide a textural record of ash venting during dome effusion. We use synchrotron-based X-ray computed tomography to characterize the particles in these tuffisites. Particle sizes in well-sorted tuffisite layers agree well with grain size distributions observed during weak ash venting at Soufrière Hills Volcano, Montserrat, and yield approximate upper and lower bounds on gas velocity and mass flux during the formation of those layers. We simulate ash dispersal with Ash3d to assess the consequences of long-lived Mono-Inyo ash venting for ash deposition and the accompanying volcanic hazards. Our results highlight the sensitivity of large-scale outcomes of volcanic eruptions to small-scale processes.

  10. Measure Guideline: Passive Vents

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Berger, David; Neri, Robin

    2016-02-05

    This document addresses the use of passive vents as a source of outdoor air in multifamily buildings. The challenges associated with implementing passive vents and the factors affecting performance are outlined. A comprehensive design methodology and quantified performance metrics are provided. Two hypothetical design examples are provided to illustrate the process. This document is intended to be useful to designers, decision-makers, and contractors implementing passive ventilation strategies. It is also intended to be a resource for those responsible for setting high-performance building program requirements, especially pertaining to ventilation and outdoor air. To ensure good indoor air quality, a dedicated sourcemore » of outdoor air is an integral part of high-performance buildings. Presently, there is a lack of guidance pertaining to the design and installation of passive vents, resulting in poor system performance. This report details the criteria necessary for designing, constructing, and testing passive vent systems to enable them to provide consistent and reliable levels of ventilation air from outdoors.« less

  11. 40 CFR 63.8240 - What are my monitoring requirements?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Mercury Emissions From Mercury Cell...? For each by-product hydrogen stream, each end box ventilation system vent, and each mercury thermal...

  12. 40 CFR 63.8240 - What are my monitoring requirements?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Mercury Emissions From Mercury Cell...? For each by-product hydrogen stream, each end box ventilation system vent, and each mercury thermal...

  13. 40 CFR 63.8240 - What are my monitoring requirements?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Mercury Emissions From Mercury Cell...? For each by-product hydrogen stream, each end box ventilation system vent, and each mercury thermal...

  14. 40 CFR 63.8240 - What are my monitoring requirements?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Mercury Emissions From Mercury Cell...? For each by-product hydrogen stream, each end box ventilation system vent, and each mercury thermal...

  15. Heterotrophic Proteobacteria in the vicinity of diffuse hydrothermal venting.

    PubMed

    Meier, Dimitri V; Bach, Wolfgang; Girguis, Peter R; Gruber-Vodicka, Harald R; Reeves, Eoghan P; Richter, Michael; Vidoudez, Charles; Amann, Rudolf; Meyerdierks, Anke

    2016-12-01

    Deep-sea hydrothermal vents are highly dynamic habitats characterized by steep temperature and chemical gradients. The oxidation of reduced compounds dissolved in the venting fluids fuels primary production providing the basis for extensive life. Until recently studies of microbial vent communities have focused primarily on chemolithoautotrophic organisms. In our study, we targeted the change of microbial community compositions along mixing gradients, focusing on distribution and capabilities of heterotrophic microorganisms. Samples were retrieved from different venting areas within the Menez Gwen hydrothermal field, taken along mixing gradients, including diffuse fluid discharge points, their immediate surroundings and the buoyant parts of hydrothermal plumes. High throughput 16S rRNA gene amplicon sequencing, fluorescence in situ hybridization, and targeted metagenome analysis were combined with geochemical analyses. Close to diffuse venting orifices dominated by chemolithoautotrophic Epsilonproteobacteria, in areas where environmental conditions still supported chemolithoautotrophic processes, we detected microbial communities enriched for versatile heterotrophic Alpha- and Gammaproteobacteria. The potential for alkane degradation could be shown for several genera and yet uncultured clades. We propose that hotspots of chemolithoautotrophic life support a 'belt' of heterotrophic bacteria significantly different from the dominating oligotrophic microbiota of the deep sea. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

  16. 40 CFR Table 5 to Subpart Uuuu of... - Continuous Compliance With Emission Limits and Work Practice Standards

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... material balance that includes the pertinent data used to determine the percent reduction of total sulfide... material balance; and (3) complying with the continuous compliance requirements for closed-vent systems. 2... material balance that includes the pertinent data used to determine the percent reduction of toluene...

  17. 40 CFR Table 5 to Subpart Uuuu of... - Continuous Compliance With Emission Limits and Work Practice Standards

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... material balance that includes the pertinent data used to determine the percent reduction of total sulfide... material balance; and (3) complying with the continuous compliance requirements for closed-vent systems. 2... material balance that includes the pertinent data used to determine the percent reduction of toluene...

  18. Vapor segregation and loss in basaltic melts

    USGS Publications Warehouse

    Edmonds, M.; Gerlach, T.M.

    2007-01-01

    Measurements of volcanic gases at Pu'u'O??'o??, Kilauea Volcano, Hawai'i, reveal distinct degassing regimes with respect to vapor segregation and loss during effusive activity in 2004-2005. Three styles of vapor loss are distinguished by the chemical character of the emitted volcanic gases, measured by open path Fourier transform infrared spectroscopy: 1 persistent continuous gas emission, 2 gas piston events, and 3 lava spattering. Persistent continuous gas emission is associated with magma ascent and degassing beneath the crater vents, then eruption of the degassed magma from flank vents. Gas piston events are the result of static gas accumulation at depths of 400-900 m beneath Pu'u'O??'o??. A CO2-rich gas slug travels up the conduit at a few meters per second, displacing magma as it expands. Lava spattering occurs due to dynamic bubble coalescence in a column of relatively stagnant magma. The Large gas bubbles are H2O rich and are generated by open-system degassing at depths of <150 m. Static gas accumulation and dynamic bubble coalescence are both manifestations of vapor segregation in basaltic melts, but their implications differ. Accumulation and segregation of CO2-rich vapor at depth does not deplete the melt of H2O (required to drive lava fountains near to the surface) and therefore gas piston events can occur interspersed with lava fountaining activity. Lava spattering, however, efficiently strips H2O-rich vapor from magma beneath the crater vents; the magma must then erupt effusively from vents on the flank of the cone. ?? 2007 The Geological Society of America.

  19. Vapor segregation and loss in basaltic melts

    NASA Astrophysics Data System (ADS)

    Edmonds, Marie; Gerlach, Terrence M.

    2007-08-01

    Measurements of volcanic gases at Pu'u‘Ō’ō, Kilauea Volcano, Hawai'i, reveal distinct degassing regimes with respect to vapor segregation and loss during effusive activity in 2004-2005. Three styles of vapor loss are distinguished by the chemical character of the emitted volcanic gases, measured by open path Fourier transform infrared spectroscopy: (1) persistent continuous gas emission, (2) gas piston events, and (3) lava spattering. Persistent continuous gas emission is associated with magma ascent and degassing beneath the crater vents, then eruption of the degassed magma from flank vents. Gas piston events are the result of static gas accumulation at depths of 400-900 m beneath Pu'u‘Ō’ō. A CO2-rich gas slug travels up the conduit at a few meters per second, displacing magma as it expands. Lava spattering occurs due to dynamic bubble coalescence in a column of relatively stagnant magma. The large gas bubbles are H2O rich and are generated by open-system degassing at depths of <150 m. Static gas accumulation and dynamic bubble coalescence are both manifestations of vapor segregation in basaltic melts, but their implications differ. Accumulation and segregation of CO2-rich vapor at depth does not deplete the melt of H2O (required to drive lava fountains near to the surface) and therefore gas piston events can occur interspersed with lava fountaining activity. Lava spattering, however, efficiently strips H2O-rich vapor from magma beneath the crater vents; the magma must then erupt effusively from vents on the flank of the cone.

  20. Characterizing Microbial Community and Geochemical Dynamics at Hydrothermal Vents Using Osmotically Driven Continuous Fluid Samplers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Robidart, Julie C.; Callister, Stephen J.; Song, Peng F.

    2013-05-07

    Microbes play a key role in mediating all aquatic biogeochemical cycles, and ongoing efforts are aimed at better understanding the relationships between microbial phylogenetic and physiological diversity, and habitat physical and chemical characteristics. Establishing such relationships is facilitated by sampling and studying microbiology and geochemistry at the appropriate spatial and temporal scales, to access information on the past and current environmental state that contributes to observed microbial abundances and activities. A modest number of sampling systems exist to date, few of which can be used in remote, harsh environments such as hydrothermal vents, where the ephemeral nature of venting underscoresmore » the necessity for higher resolution sampling. We have developed a robust, continuous fluid sampling system for co-registered microbial and biogeochemical analyses. The osmosis-powered bio-osmosampling system (BOSS) use no electricity, collects fluids with daily resolution or better, can be deployed in harsh, inaccessible environments and can sample fluids continuously for up to five years. Here we present a series of tests to examine DNA, RNA and protein stability over time, as well as material compatability, via lab experiments. We also conducted two field deployments at deep-sea hydrothermal vents to assess changes in microbial diversity and protein expression as a function of the physico-chemical environment. Our data reveal significant changes in microbial community composition co-occurring with relatively modest changes in the geochemistry. These data additionally provide new insights into the distribution of an enigmatic sulfur oxidizing symbiont in its free-living state. Data from the second deployment reveal differences in the representation of peptides over time, underscoring the utility of the BOSS in meta-proteomic studies. In concert, these data demonstrate the efficacy of this approach, and illustrate the value of using this method to study microbial and geochemical phenomena.« less

  1. Stratigraphic architecture of hydromagmatic volcanoes that have undergone vent migration: a review of Korean case studies

    NASA Astrophysics Data System (ADS)

    Sohn, Y.

    2011-12-01

    Recent studies show that the architecture of hydromagmatic volcanoes is far more complex than formerly expected. A number of external factors, such as paleohydrology and tectonics, in addition to magmatic processes are thought to play a role in controlling the overall characteristics and architecture of these volcanoes. One of the main consequences of these controls is the migration of the active vent during eruption. Case studies of hydromagmatic volcanoes in Korea show that those volcanoes that have undergone vent migration are characterized by superposition or juxtaposition of multiple rim deposits of partial tuff rings and/or tuff cones that have contrasting lithofacies characteristics, bed attitudes, and paleoflow directions. Various causes of vent migration are inferred from these volcanoes. Large-scale collapse of fragile substrate is interpreted to have caused vent migration in the Early Pleistocene volcanoes of Jeju Island, which were built upon still unconsolidated continental shelf sediments. Late Pleistocene to Holocene volcanoes, which were built upon a stack of rigid, shield-forming lava flows, lack features due to large-scale substrate collapse and have generally simple and circular morphologies either of a tuff ring or of a tuff cone. However, ~600 m shift of the eruptive center is inferred from one of these volcanoes (Ilchulbong tuff cone). The vent migration in this volcano is interpreted to have occurred because the eruption was sourced by multiple magma batches with significant eruptive pauses in between. The Yangpori diatreme in a Miocene terrestrial half-graben basin in SE Korea is interpreted to be a subsurface equivalent of a hydromagmatic volcano that has undergone vent migration. The vent migration here is inferred to have had both vertical and lateral components and have been caused by an abrupt tectonic activity near the basin margin. In all these cases, rimbeds or diatreme fills derived from different source vents are bounded by either prominent or subtle, commonly laterally extensive truncation surfaces or stratigraphic discontinuities. Careful documentation of these surfaces and discontinuities thus appears vital to proper interpretation of eruption history, morphologic evolution, and even deep-seated magmatic processes of a hydromagmatic volcano. In this respect, the technique known as 'allostratigraphy' appears useful in mapping, correlation, and interpretation of many hydrovolcanic edifices and sequences.

  2. Video monitoring reveals pulsating vents and propagation path of fissure eruption during the March 2011 Pu'u 'Ō'ō eruption, Kilauea volcano

    NASA Astrophysics Data System (ADS)

    Witt, Tanja; Walter, Thomas R.

    2017-01-01

    Lava fountains are a common eruptive feature of basaltic volcanoes. Many lava fountains result from fissure eruptions and are associated with the alignment of active vents and rising gas bubbles in the conduit. Visual reports suggest that lava fountain pulses may occur in chorus at adjacent vents. The mechanisms behind such a chorus of lava fountains and the underlying processes are, however, not fully understood. The March 2011 eruption at Pu'u 'Ō'ō (Kilauea volcano) was an exceptional fissure eruption that was well monitored and could be closely approached by field geologists. The fissure eruption occurred along groups of individual vents aligned above the feeding dyke. We investigate video data acquired during the early stages of the eruption to measure the height, width and velocity of the ejecta leaving eight vents. Using a Sobel edge-detection algorithm, the activity level of the lava fountains at the vents was determined, revealing a similarity in the eruption height and frequency. Based on this lava fountain time series, we estimate the direction and degree of correlation between the different vents. We find that the height and velocity of the eruptions display a small but systematic shift in time along the vents, indicating a lateral migration of lava fountaining at a rate of 11 m/s from W to E. This finding is in agreement with a propagation model of a pressure wave originating at the Kilauea volcano and propagating through the dyke at 10 m/s from W to E. Based on this approach from videos only 30 s long, we are able to obtain indirect constraints on the physical dyke parameters, with important implications for lateral magma flow processes at depth. This work shows that the recording and analysis of video data provide important constraints on the mechanisms of lava fountain pulses. Even though the video sequence is short, it allows for the confirmation of the magma propagation direction and a first-order estimation of the dyke dimensions.

  3. Volcanic Lightning, Pyroclastic Density Currents, Ballistic Fall, Vent Tremor, and One Very Loud Blast: Acoustic Analysis of the 14 July 2013 Vulcanian Eruption at Tungurahua, Ecuador.

    NASA Astrophysics Data System (ADS)

    Anderson, J.; Johnson, J. B.; Steele, A. L.; Anzieta, J. C.; Ortiz, H. D.; Hall, M. L.; Ruiz, M. C.

    2014-12-01

    Acoustic recordings reveal a variety of volcanic activities during an exceptionally loud vulcanian eruption at Tungurahua. A period of several months of mild surface activity came to an abrupt end with the emission of a powerful blast wave heard at least 180 km away. Sensors 2080 m from the vent recorded a stepped rise to its maximum overpressure of 1220 Pa (corresponding to a sound pressure level of 156 dB) and its unusually long dominant period of 5.6 s. We discuss source processes that produced the blast wave, considering that wave propagation could be nonlinear near the vent because of high overpressures. More than an hour of acoustic activity was recorded after the blast wave, including sound from falling ballistics, reflections of the blast wave from nearby mountains, pyroclastic density currents, and acoustic tremor at the vent. Glitches in the acoustic records related to plume lightning were also serendipitously observed, although thunder could not be unambiguously identified. We discuss acoustic signatures of falling ballistics and pyroclastic density currents and how array-style deployments and analytic methods can be used to reveal them. Placement of sensors high on the volcano's slopes facilitated resolving these distinct processes. This study demonstrates that near-vent, array-style acoustic installations can be used to monitor various types of volcanic activity.

  4. Development and relationship of monogenetic and polygenetic volcanic fields in time and space.

    NASA Astrophysics Data System (ADS)

    Germa, Aurelie; Connor, Chuck; Connor, Laura; Malservisi, Rocco

    2013-04-01

    The classification of volcanic systems, developed by G. P. L. Walker and colleagues, relates volcano morphology to magma transport and eruption processes. In general, distributed monogenetic volcanic fields are characterized by infrequent eruptions, low average output rate, and a low spatial intensity of the eruptive vents. In contrast, central-vent-dominated systems, such as stratovolcanoes, central volcanoes and lava shields are characterized by frequent eruptions, higher average flux rates, and higher spatial intensity of eruptive vents. However, it has been observed that a stratovolcano is often associated to parasitic monogenetic vents on its flanks, related to the central silicic systems, and surrounded by an apron of monogenetic edifices that are part of the volcanic field but independent from the principal central system. It appears from spatial distribution and time-volume relationships that surface area of monogenetic fields reflects the lateral extent of the magma source region and the lack of magma focusing mechanisms. In contrast, magma is focused through a unique conduit system for polygenetic volcanoes, provided by a thermally and mechanically favorable pathway toward the surface that is maintained by frequent and favorable stress conditions. We plan to relate surface observations of spatio-temporal location of eruptive vents and evolution of the field area through time to processes that control magma focusing during ascent and storage in the crust. We choose to study fields that range from dispersed to central-vent dominated, through transitional fields (central felsic system with peripheral field of monogenetic vents independent from the rhyolitic system). We investigate different well-studied volcanic fields in the Western US and Western Europe in order to assess influence of the geodynamic setting and tectonic stress on the spatial distribution of magmatism. In summary, incremental spatial intensity maps should reveal how fast a central conduit is created during the development of a volcanic field, and how this could influence the outbreak of dispersed monogenetic volcanoes that are not geochemically linked to the central system.

  5. 9 CFR 381.305 - Equipment and procedures for heat processing systems.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... plates. Whenever one or more divider plates are used between any two layers of containers or placed on... from several still retorts shall lead to the atmosphere. The manifold header shall not be controlled by...) Venting through multiple 1 inch (2.5 cm) vents discharging directly to the atmosphere. EC11SE91.047...

  6. 9 CFR 381.305 - Equipment and procedures for heat processing systems.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... plates. Whenever one or more divider plates are used between any two layers of containers or placed on... from several still retorts shall lead to the atmosphere. The manifold header shall not be controlled by...) Venting through multiple 1 inch (2.5 cm) vents discharging directly to the atmosphere. EC11SE91.047...

  7. 9 CFR 381.305 - Equipment and procedures for heat processing systems.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... plates. Whenever one or more divider plates are used between any two layers of containers or placed on... from several still retorts shall lead to the atmosphere. The manifold header shall not be controlled by...) Venting through multiple 1 inch (2.5 cm) vents discharging directly to the atmosphere. EC11SE91.047...

  8. 40 CFR 63.116 - Process vent provisions-performance test methods and procedures to determine compliance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... conduct a performance test to determine percent emission reduction or outlet organic HAP or TOC... organic HAP concentration and percent reduction may be measured as either total organic HAP or as TOC... measurement of total organic HAP or TOC (minus methane and ethane) concentrations in all vent streams and...

  9. 40 CFR 60.611 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... recovery device or series of such devices applied to the same process stream. Total organic compounds (TOC...(d)(5) and § 60.614(e) and TOC concentration as required in § 60.615(b)(4) and § 60.615(g)(4), those... requirement per unit reduction of TOC associated with an individual air oxidation vent stream, based on vent...

  10. 40 CFR Table 5 of Subpart Bbbbbbb... - Reporting Requirements

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... vent streams from equipment in target HAP service to a PM control device with a PM percent reduction efficiency of 95 percent (98 percent for new sources) or an outlet concentration of 0.03 gr/dscf or less a... requirement to route all process vent streams from equipment in target HAP service to a PM control device that...

  11. 40 CFR Table 5 of Subpart Bbbbbbb... - Reporting Requirements

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... vent streams from equipment in target HAP service to a PM control device with a PM percent reduction efficiency of 95 percent (98 percent for new sources) or an outlet concentration of 0.03 gr/dscf or less a... requirement to route all process vent streams from equipment in target HAP service to a PM control device that...

  12. 40 CFR Table 5 of Subpart Bbbbbbb... - Reporting Requirements

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... vent streams from equipment in target HAP service to a PM control device with a PM percent reduction efficiency of 95 percent (98 percent for new sources) or an outlet concentration of 0.03 gr/dscf or less a... requirement to route all process vent streams from equipment in target HAP service to a PM control device that...

  13. 40 CFR Table 5 of Subpart Bbbbbbb... - Reporting Requirements

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... vent streams from equipment in target HAP service to a PM control device with a PM percent reduction efficiency of 95 percent (98 percent for new sources) or an outlet concentration of 0.03 gr/dscf or less a... requirement to route all process vent streams from equipment in target HAP service to a PM control device that...

  14. 40 CFR Table 5 of Subpart Bbbbbbb... - Reporting Requirements

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... vent streams from equipment in target HAP service to a PM control device with a PM percent reduction efficiency of 95 percent (98 percent for new sources) or an outlet concentration of 0.03 gr/dscf or less a... requirement to route all process vent streams from equipment in target HAP service to a PM control device that...

  15. 40 CFR 63.1426 - Process vent requirements for determining organic HAP concentration, control efficiency, and...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... performance test for those control techniques in accordance with paragraph (b)(6) of this section. The design..., immediately preceding the use of the control technique. A design evaluation shall also address other vent... paragraph (f)(1)(i) of this section, the design evaluation shall document the control efficiency and address...

  16. Identification of possible recent water/lava source vents in the Cerberus plains: Stratigraphic andcrater count age constraints

    NASA Astrophysics Data System (ADS)

    Thomas, Rebecca J.

    2013-04-01

    In order to investigate sources of lava and water to the Cerberus plains of Mars, geomorphological mapping on High Resolution Imaging Science Experiment (HiRISE) images was carried out to reveal the history of activity of fissures and pits which lie upstream of channels and deposits associated with a wrinkle ridge near Cerberus Fossae. The fissures and pits are superbly exposed and imaged, and flows and channels emanate directly from them, interpreted as clear evidence that these are vents. The mapping establishes stratigraphic relationships between the plains and the channels and deposits originating from the vents, establishing the vent history. For example, to the south of the wrinkle ridge, both incised channels and leveed flows extend onto the southern plain and are clearly the final phase of plains-forming activity. Conversely, to the north, vent-sourced channels only incise the plain close to the ridge—beyond that, they are overlain by large-scale regional flows that appear to have originated from the direction of Athabasca Valles. In the southeast, there is evidence of contemporaneity between vent-sourced activity and large-scale plains-forming flow that was not sourced from the vents, indicating that activity here was part of a broader process of Cerberus plains formation from multiple sources. Crater counts show all the activity to be Late Amazonian, with the latest activity tentatively dating to circa 11 Ma. Thus, this study implies that very recent outflows from these vents contributed to the formation of the Cerberus plains and constrains the timing and local flow direction of plains-forming deposits from other sources.

  17. Comparing chemolithoautotrophic subseafloor communities across geochemical gradients using meta-omics and RNA-SIP

    NASA Astrophysics Data System (ADS)

    Fortunato, C. S.; Huber, J. A.

    2015-12-01

    The chemolithoautotrophic microbial community of the rocky subseafloor potentially provides a large amount of organic carbon to the deep ocean, yet our understanding of the activity and metabolic complexity of subseafloor organisms remains poorly described. Past studies have shown that the taxonomic structure of subseafloor communities differs based on the geochemical signatures of individual vents. In this study, we expanded beyond phylogeny and used a combination of metagenomic, metatranscriptomic, and RNA-based stable isotope probing (RNA-SIP) analyses to identify the metabolic potential, expression patterns, and the active autotrophic players and genomic pathways present in venting fluids from Axial Seamount, an active submarine volcano off the coast of Oregon, USA. Low-temperature diffuse vent fluids from three hydrothermal vents, Marker 113, Marker 33, and Anemone, were filtered and preserved on the seafloor for metagenome and metatranscriptome analyses. Fluid for RNA-SIP was also collected and incubated shipboard with 13C-labeled sodium bicarbonate at 30ºC, 55ºC, and 80ºC for each vent. Taxonomically, Epsilonproteobacteria comprised a significant proportion of the community at all three vents, but each vent also had distinct groups that were abundant including SUP05 at Anemone and Methanococcus at Marker 113. Functionally, vents shared many metabolic processes including genes for denitrification, sulfur reduction and sulfur, hydrogen, and ammonium oxidation, which were present and expressed in similar abundance across all three vents. One metabolic difference between vents was the presence and expression of genes for methanogenesis, which were highly abundant and expressed at Marker 113, in lower abundance and expression at Marker 33, and not present at Anemone. RNA-SIP analysis is ongoing but initial results from Marker 113 revealed that at mesophilic, thermophilic, or hyperthemophilic temperatures, different genera and autotrophic metabolisms dominated. In addition, RNA-SIP showed that at 80ºC a different hyperthermophilic group dominated at each vent. Overall, this study demonstrates the metabolic and taxonomic diversity of the subseafloor and better characterizes the subseafloor chemolithoautotrophs and their role in biogeochemical cycling.

  18. 40 CFR 63.8243 - What equations and procedures must I use to demonstrate continuous compliance?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Pollutants: Mercury Emissions From Mercury Cell Chlor-Alkali Plants Continuous Compliance Requirements § 63... hydrogen streams and end box ventilation system vents. For each consecutive 52-week period, you must determine the g Hg/Mg Cl2 produced from all by-product hydrogen streams and all end box ventilation system...

  19. 40 CFR 63.8243 - What equations and procedures must I use to demonstrate continuous compliance?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Pollutants: Mercury Emissions From Mercury Cell Chlor-Alkali Plants Continuous Compliance Requirements § 63... hydrogen streams and end box ventilation system vents. For each consecutive 52-week period, you must determine the g Hg/Mg Cl2 produced from all by-product hydrogen streams and all end box ventilation system...

  20. 40 CFR 63.8243 - What equations and procedures must I use to demonstrate continuous compliance?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Pollutants: Mercury Emissions From Mercury Cell Chlor-Alkali Plants Continuous Compliance Requirements § 63... hydrogen streams and end box ventilation system vents. For each consecutive 52-week period, you must determine the g Hg/Mg Cl2 produced from all by-product hydrogen streams and all end box ventilation system...

  1. Continuous production of ethanol by use of flocculent zymomonas mobilis

    DOEpatents

    Arcuri, Edward J.; Donaldson, Terrence L.

    1983-01-01

    Ethanol is produced by means of a floc-forming strain of Zymomonas mobilis bacteria. Gas is vented along the length of a column containing the flocculent bacteria to preclude disruption of liquid flow.

  2. 40 CFR 65.107 - Standards: Pumps in light liquid service.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... or fuel gas system or connected by a closed vent system to a control device that complies with the requirements of § 65.115; or (C) Equipped with a closed-loop system that purges the barrier fluid into a... section. (3) Routed to a process or fuel gas system or equipped with a closed vent system. Any pump that...

  3. Building America Case Study: Design Guidance for Passive Vents in New Construction Multifamily Buildings, New York, New York

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    2016-02-01

    This document addresses the use of passive vents as a source of outdoor air in multifamily buildings. The challenges associated with implementing passive vents and the factors affecting performance are outlined. A comprehensive design methodology and quantified performance metrics are provided. Two hypothetical design examples are provided to illustrate the process. This document is intended to be useful to designers, decision-makers, and contractors implementing passive ventilation strategies. It is also intended to be a resource for those responsible for setting high-performance building program requirements, especially pertaining to ventilation and outdoor air. To ensure good indoor air quality, a dedicated sourcemore » of outdoor air is an integral part of high-performance buildings. Presently, there is a lack of guidance pertaining to the design and installation of passive vents, resulting in poor system performance. This report details the criteria necessary for designing, constructing, and testing passive vent systems to enable them to provide consistent and reliable levels of ventilation air from outdoors.« less

  4. Experimental study of geysers through a vent pipe connected to flowing sewers.

    PubMed

    Huang, Biao; Wu, Shiqiang; Zhu, David Z; Schulz, Harry E

    2017-04-01

    Geysers of air-water mixtures in urban drainage systems is receiving considerable attention due to public safety concerns. However, the geyser formation process and its relation with air release from pressurized pipes are still relatively little known. A large-scale physical model, that consisted of a main tunnel with a diameter of 270 mm and a length of 25 m connecting two reservoirs and a vertical vent pipe, was established to investigate geyser evolution and pressure transients. Experimental results including dynamic pressure data and high speed videos were analysed in order to characterize geysering flow through the vent pipe. Pressure transients were observed during geysering events. Their amplitudes were found to be about three times the driving pressure head and their periods were close to the classic surge tank predictions. The influence of flow rate and vent pipe size were examined: geyser heights and pressure peaks decreased for small flow rate and large diameter vent pipe. It is suggested that geyser heights are related with the pressure head and the density of the air-water mixture.

  5. LOX Tank Helium Removal for Propellant Scavenging

    NASA Technical Reports Server (NTRS)

    Chato, David J.

    2009-01-01

    System studies have shown a significant advantage to reusing the hydrogen and oxygen left in these tanks after landing on the Moon in fuel cells to generate power and water for surface systems. However in the current lander concepts, the helium used to pressurize the oxygen tank can substantially degrade fuel cell power and water output by covering the reacting surface with inert gas. This presentation documents an experimental investigation of methods to remove the helium pressurant while minimizing the amount of the oxygen lost. This investigation demonstrated that significant quantities of Helium (greater than 90% mole fraction) remain in the tank after draining. Although a single vent cycle reduced the helium quantity, large amounts of helium remained. Cyclic venting appeared to be more effective. Three vent cycles were sufficient to reduce the helium to small (less than 0.2%) quantities. Two vent cycles may be sufficient since once the tank has been brought up to pressure after the second vent cycle the helium concentration has been reduced to the less than 0.2% level. The re-pressurization process seemed to contribute to diluting helium. This is as expected since in order to raise the pressure liquid oxygen must be evaporated. Estimated liquid oxygen loss is on the order of 82 pounds (assuming the third vent cycle is not required).

  6. Vulnerability of Deep-sea Hydrothermal Vent Communities to Disturbance: Evidence from Post-eruption Colonization on the East Pacific Rise

    NASA Astrophysics Data System (ADS)

    Mills, S. W.; Le Bris, N.; Beaulieu, S.; Sievert, S. M.; Mullineaux, L. S.

    2016-02-01

    Hydrothermal vents on fast-spreading ridges experience frequent disturbances that exterminate local faunal communities. Vent communities generally are expected to be resilient to natural disturbance, but they may instead undergo a successional path to an alternative state, due to changes in larval supply, vent-fluid chemistry or physical habitat. Furthermore, recolonization after human disturbance, such as mining of mineral deposits, may be quite different. Resilience is important on a larger scale, as it influences diversity and dynamics in the regional metacommunity. In early 2006 a catastrophic eruption paved over most existing communities near 9°50'N on the East Pacific Rise, creating a natural clearance experiment and opportunity to investigate resilience. We had been monitoring recruitment at the site before the eruption, and have continued through 2014. In the first year post-eruption we found significant differences in species composition from pre-eruption communities, most notably the arrival of one limpet species Ctenopelta porifera that had been recorded previously only from 13°N, and the dominance of another, Lepetodrilus tevnianus, that had not been present in years prior to the event. After 2 years, C. porifera numbers had declined precipitously, most likely due to a decrease in vent fluid flux, while L. tevnianus persisted and a diverse suite of additional species started to arrive. Over the next 8 years, changes in species diversity and composition indicated that the community was transitioning toward a state similar to its pre-eruption condition, but key differences remained. These results demonstrate that environment, larval supply and foundation species all influence succession of vent communities on the East Pacific Rise, and that the trajectory and rate of recovery are difficult to predict even after natural disturbance in this well-studied locale.

  7. Subseafloor Microbial Life in Venting Fluids from the Mid Cayman Rise Hydrothermal System

    NASA Astrophysics Data System (ADS)

    Huber, J. A.; Reveillaud, J.; Reddington, E.; McDermott, J. M.; Sylva, S. P.; Breier, J. A.; German, C. R.; Seewald, J.

    2012-12-01

    In hard rock seafloor environments, fluids emanating from hydrothermal vents are one of the best windows into the subseafloor and its resident microbial community. The functional consequences of an extensive population of microbes living in the subseafloor remains unknown, as does our understanding of how these organisms interact with one another and influence the biogeochemistry of the oceans. Here we report the abundance, activity, and diversity of microbes in venting fluids collected from two newly discovered deep-sea hydrothermal vents along the ultra-slow spreading Mid-Cayman Rise (MCR). Fluids for geochemical and microbial analysis were collected from the Von Damm and Piccard vent fields, which are located within 20 km of one another, yet have extremely different thermal, geological, and depth regimes. Geochemical data indicates that both fields are highly enriched in volatiles, in particular hydrogen and methane, important energy sources for and by-products of microbial metabolism. At both sites, total microbial cell counts in the fluids ranged in concentration from 5 x 10 4 to 3 x 10 5 cells ml-1 , with background seawater concentrations of 1-2 x 10 4 cells ml-1 . In addition, distinct cell morphologies and clusters of cells not visible in background seawater were seen, including large filaments and mineral particles colonized by microbial cells. These results indicate local enrichments of microbial communities in the venting fluids, distinct from background populations, and are consistent with previous enumerations of microbial cells in venting fluids. Stable isotope tracing experiments were used to detect utilization of acetate, formate, and dissolve inorganic carbon and generation of methane at 70 °C under anaerobic conditions. At Von Damm, a putatively ultra-mafic hosted site located at ~2200 m with a maximum temperature of 226 °C, stable isotope tracing experiments indicate methanogenesis is occurring in most fluid samples. No activity was detected in Piccard vent fluids, a basalt-hosted black smoker site located at ~4950 m with a maximum temperature of 403 °C. However, hyperthermophilic and thermophilic heterotrophs of the genus Thermococcus were isolated from Piccard vent fluids, but not Von Damm. These obligate anaerobes, growing optimally at 55-90 °C, are ubiquitous at hydrothermal systems and serve as a readily cultivable indicator organism of subseafloor populations. Finally, molecular analysis of vent fluids is on-going and will define the microbial population structure in this novel ecosystem and allow for direct comparisons with other deep-sea and subsurface habitats as part of our continuing efforts to explore the deep microbial biosphere on Earth.

  8. Pu'u 'Ō'ō-Kūpaianaha eruption of Kilauea, November 1991-February 1994; field data and flow maps

    USGS Publications Warehouse

    Heliker, C. Christina; Mangan, Margaret T.; Mattox, Tari N.; Kauahikaua, James P.

    1998-01-01

    The Pu'u 'Ō'ō-Kūpaianaha eruption on the east rift zone of Kīlauea, which began in January 1983, is the longest-lived rift zone eruption of the last two centuries. By 1994, a broad field of lava, nearly 1 km3 in volume and 12 km wide at the coast, had buried 87 km2 of the volcano's south flank. The initial six months of fissure eruptions (episodes 1-3) were followed by three years of episodic lava fountaining from the Pu'u 'Ō'ō vent (episodes 4–47). In July 1986, after two days of fissure eruptions up- and downrift from Pu'u 'Ō'ō (episodes 48a and 48b), the eruption shifted to a new vent, Kūpaianaha, 3.5 km downrift. For the next five-and-a-half years (episode 48), Kūpaianaha was the site of nearly continuous low-level effusion. The 49th episode occurred in November 1991, when several fissures opened between Pu'u 'Ō'ō and Kūpaianaha (see Mangan and others, 1995, Bulletin of Volcanology, v. 57, p. 127-135). This three-week-long outburst was the result of the waning output of the Kūpaianaha vent, which finally died in February 1992 (see Kauahikaua and others, 1996, Bulletin of Volcanology, v. 57, p. 641-648). The third epoch of the eruption began ten days later, when vents opened on the uprift slope of the Pu'u 'Ō'ō cone. Several flank vents erupted over the next two years (episodes 50-53). In the first year, from February 1992 through February 1993, the low-level effusion was interrupted by 21 brief pauses. These ended with the beginning of episode 53 in February 1993, and for the next year, lava effusion was continuous. Episode 53 was ongoing at the end of the interval covered by this report. During the years that Kūpaianaha was active, the Pu'u 'Ō'ō conduit gradually evolved into a crater 300 m in diameter as the conduit walls collapsed. Beginning in 1987, an active lava pond was intermittently visible in the bottom of the crater; from 1990 on, the pond was almost continuously present. The Pu'u 'Ō‘ō pond drained at the beginning of episode 49 in November 1991, and the crater floor collapsed. Lava was visible in the crater by early December, and pond overflows resurfaced the crater floor, raising it to its former level of 35 m below the rim by the end of January 1992. This report includes flow-field maps and a table giving a) start and stop times of the eruptive episodes and of pauses in the eruption, b) Pu'u 'Ō'ō lava pond and crater-floor elevations, and c) elevations of the episode 50-53 vents and of the floors of the collapse pits that subsequently formed over these vents. A chronology of this interval of the eruption and an interpretation of the data included in this report can be found in Heliker and others (1998, Bulletin of Volcanology, v. 59, p. 381-393).

  9. Evaluating life-safety risk of fieldwork at New Zealand's active volcanoes

    NASA Astrophysics Data System (ADS)

    Deligne, Natalia; Jolly, Gill; Taig, Tony; Webb, Terry

    2014-05-01

    Volcano observatories monitor active or potentially active volcanoes. Although the number and scope of remote monitoring instruments and methods continues to grow, in-person field data collection is still required for comprehensive monitoring. Fieldwork anywhere, and especially in mountainous areas, contains an element of risk. However, on volcanoes with signs of unrest, there is an additional risk of volcanic activity escalating while on site, with potentially lethal consequences. As an employer, a volcano observatory is morally and sometimes legally obligated to take reasonable measures to ensure staff safety and to minimise occupational risk. Here we present how GNS Science evaluates life-safety risk for volcanologists engaged in fieldwork on New Zealand volcanoes with signs of volcanic unrest. Our method includes several key elements: (1) an expert elicitation for how likely an eruption is within a given time frame, (2) quantification of, based on historical data when possible, given a small, moderate, or large eruption, the likelihood of exposure to near-vent processes, ballistics, or surge at various distances from the vent, and (3) estimate of fatality rate given exposure to these volcanic hazards. The final product quantifies hourly fatality risk at various distances from a volcanic vent; various thresholds of risk (for example, zones with more than 10-5 hourly fatality risk) trigger different levels of required approval to undertake work. Although an element of risk will always be present when conducting fieldwork on potentially active volcanoes, this is a first step towards providing objective guidance for go/no go decisions for volcanic monitoring.

  10. 40 CFR Table 2 to Subpart G of... - Process Vents-Coefficients for Total Resource Effectiveness for New Source Nonhalogenated and...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Nonhalogenated Flare 0.5276 0.0998 −2.096×10−3 −2.000×10−4 Thermal Incinerator 0 Percent Heat Recovery 0.4068 0.0171 8.664×10−3 −3.162×10−4 Thermal Incinerator 70 Percent Heat Recovery 0.6868 3.209×10−3 3.546×10−3 1... Process Vents, Storage Vessels, Transfer Operations, and Wastewater Pt. 63, Subpt. G, Table 2 Table 2 to...

  11. 40 CFR Table 1 to Subpart G of... - Process Vents-Coefficients for Total Resource Effectiveness for Existing Source Nonhalogenated...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Coefficients a b c d Nonhalogenated Flare 1.935 3.660×10−1 −7.687×10−3 −7.333×10−4 Thermal Incinerator 0 Percent Heat Recovery 1.492 6.267×10−2 3.177×10−2 −1.159×10−3 Thermal Incinerator 70 Percent Heat Recovery... for Process Vents, Storage Vessels, Transfer Operations, and Wastewater Pt. 63, Subpt. G, Table 1...

  12. Near-vent chemical processes in a hydrothermal plume: Insights from an integrated study of the Endeavour segment

    NASA Astrophysics Data System (ADS)

    Coogan, L. A.; Attar, A.; Mihaly, S. F.; Jeffries, M.; Pope, M.

    2017-04-01

    The Endeavour segment of the Juan de Fuca mid-ocean ridge is one of the best studied ridge segments and has recently been instrumented as part of Ocean Networks Canada's NEPTUNE cabled observatory. Here we investigate the interaction between high-temperature vent fluids and the overlying water column. A new tow-yo survey found that the average temperature anomaly in the neutrally buoyant plume was ˜0.043°C. The water column temperature and light attenuation anomalies correlate linearly in some areas of the plume but in other areas there is a low light attenuation anomaly relative to the temperature anomaly. This temperature excess is interpreted to reflect heat input through (particle-poor) diffuse flow. If this is correct, about half of the heat flux along the Endeavour segment comes from diffuse flow. Sediment trap and push core data show that the mass accumulation rate of the hydrothermal component of the sediments decreases rapidly with distance from the major vent fields. Large changes in the composition of the hydrothermal component of the sediments also occur with distance from the vent fields. The composition of the sediments indicates (i) sulfides precipitate early and accumulate most rapidly close to the vents with a preferential order of element removal from the plume of Cd > Ag > Cu > Co ˜ Fe; (ii) barite is deposited somewhat further from the vents. Strontium and Pb appear to be strongly incorporated in barite and/or other sulfate minerals; (iii) at most a few percent of the mass of these "insoluble" elements that is vented gets deposited within 1.5 km of the vents.

  13. High-throughput sequencing and analysis of the gill tissue transcriptome from the deep-sea hydrothermal vent mussel Bathymodiolus azoricus

    PubMed Central

    2010-01-01

    Background Bathymodiolus azoricus is a deep-sea hydrothermal vent mussel found in association with large faunal communities living in chemosynthetic environments at the bottom of the sea floor near the Azores Islands. Investigation of the exceptional physiological reactions that vent mussels have adopted in their habitat, including responses to environmental microbes, remains a difficult challenge for deep-sea biologists. In an attempt to reveal genes potentially involved in the deep-sea mussel innate immunity we carried out a high-throughput sequence analysis of freshly collected B. azoricus transcriptome using gills tissues as the primary source of immune transcripts given its strategic role in filtering the surrounding waterborne potentially infectious microorganisms. Additionally, a substantial EST data set was produced and from which a comprehensive collection of genes coding for putative proteins was organized in a dedicated database, "DeepSeaVent" the first deep-sea vent animal transcriptome database based on the 454 pyrosequencing technology. Results A normalized cDNA library from gills tissue was sequenced in a full 454 GS-FLX run, producing 778,996 sequencing reads. Assembly of the high quality reads resulted in 75,407 contigs of which 3,071 were singletons. A total of 39,425 transcripts were conceptually translated into amino-sequences of which 22,023 matched known proteins in the NCBI non-redundant protein database, 15,839 revealed conserved protein domains through InterPro functional classification and 9,584 were assigned with Gene Ontology terms. Queries conducted within the database enabled the identification of genes putatively involved in immune and inflammatory reactions which had not been previously evidenced in the vent mussel. Their physical counterpart was confirmed by semi-quantitative quantitative Reverse-Transcription-Polymerase Chain Reactions (RT-PCR) and their RNA transcription level by quantitative PCR (qPCR) experiments. Conclusions We have established the first tissue transcriptional analysis of a deep-sea hydrothermal vent animal and generated a searchable catalog of genes that provides a direct method of identifying and retrieving vast numbers of novel coding sequences which can be applied in gene expression profiling experiments from a non-conventional model organism. This provides the most comprehensive sequence resource for identifying novel genes currently available for a deep-sea vent organism, in particular, genes putatively involved in immune and inflammatory reactions in vent mussels. The characterization of the B. azoricus transcriptome will facilitate research into biological processes underlying physiological adaptations to hydrothermal vent environments and will provide a basis for expanding our understanding of genes putatively involved in adaptations processes during post-capture long term acclimatization experiments, at "sea-level" conditions, using B. azoricus as a model organism. PMID:20937131

  14. In-Situ pH Measurements in Mid-Ocean Ridge Hydrothermal Vent Fluids: Constraints on Subseafloor Alteration Processes at Crustal Depths

    NASA Astrophysics Data System (ADS)

    Schaen, A. T.; Ding, K.; Seyfried, W. E.

    2013-12-01

    Developments in electrochemistry and material science have facilitated the construction of ceramic (YSZ) based chemical sensor systems that can be used to measure and monitor pH and redox in aqueous fluids at elevated temperatures and pressures. In recent years, these sensor systems have been deployed to acquire real-time and time series in-situ data for high-temperature hydrothermal vent fluids at the Main Endeavour Field (Juan de Fuca Ridge), 9oN (East Pacific Rise), and at the ultramafic-hosted Rainbow field (36oN, Mid-Atlantic Ridge). Here we review in-situ pH data measured at these sites and apply these data to estimate the pH of fluids ascending to the seafloor from hydrothermal alteration zones deeper in the crust. In general, in-situ pH measured at virtually all vent sites is well in excess of that measured shipboard owing to the effects of temperature on the distribution of aqueous species and the solubility of metal sulfides, especially Cu and Zn, originally dissolved in the vent fluids. In situ pH measurements determined at MEF (Sully vent) and EPR 9oN (P-vent) in 2005 and 2008 were 4.4 ×0.02 and 5.05×0.05, respectively. The temperature and pressure (seafloor) of the vent fluids at each of the respective sites were 356oC and 220 bar, and 380oC and 250 bar. Plotting these data with respect to fluid density reveals that the in-situ pH of each vent fluid is approximately 1.5 pH units below neutrality. The density-pH (in-situ) correlation, however, is important because it provides a means from which the vent fluids were derived. Using dissolved silica and chloride from fluid samples at the MEF (Sully) suggest T/P conditions of approximately 435oC, 380 bar, based on quartz-fluid and NaCl-H2O systems. At the fluid density calculated for these conditions, pH (in-situ) is predicted to be ~6.2. Attempts are presently underway to assess the effect of the calculated pH on metal sulfide and silicate (e.g., plagioclase, chlorite) solubility in comparison with constraints imposed by the full range of chemical components in the vent fluids sampled and analyzed in association with pH (in-situ) measurements. Since pH is a master variable in all geochemical systems, the novel approach proposed here may provide new insight on hydrothermal alteration processes at conditions difficult or impossible to assess by more traditional means, ultimately influencing hydrothermal fluid fluxes.

  15. Web-based volcano monitoring data from the Pu‘u ‘O‘o eruptive vent (Kilauea Volcano, Hawai‘i) as a tool for geoscience education

    NASA Astrophysics Data System (ADS)

    Poland, M. P.; Townson, R.; Loren, A.; Brooks, B. A.; Foster, J. H.

    2009-12-01

    A significant challenge in college and university geoscience courses is conveying the dynamic nature of the Earth to students. The Internet, however, offers an opportunity to engage classes by making accessible the best examples of current geologic activity, regardless of location. In volcanology, Kilauea, Hawai‘i, is well known as one of the most active volcanoes in the world, and the Web site for the U.S. Geological Survey’s Hawaiian Volcano Observatory offers a daily update of volcanic activity that is followed by people around the globe. The Pu‘u ‘O‘o eruptive vent, on Kilauea‘s east rift zone, has been the focus of near continuous eruption since 1983, experiencing cycles of growth and collapse, high lava fountains, lava lakes, and other phenomena over the course of its existence. To track volcanic activity, various types of monitoring instruments have been installed on and around Pu‘u ‘O‘o, including (as of August 2009) two webcams, one short-period seismometer, one broadband seismometer, seven continuous GPS stations, and two continuous borehole tiltmeters. Monitoring data from Pu‘u ‘O‘o will be made available via the Internet as part of a collaborative research and education project between the Hawaiian Volcano Observatory, National Aeronautics and Space Administration, and University of Hawai‘i at Mānoa. The educational Web site is intended for use in college and university courses, from introductory science classes to graduate-level seminars. Scheduled to come on line by fall 2009, the Web site will provide tools to explore current monitoring results from the eruptive vent. Geophysical data, such as GPS, seismic, and tilt measurements, will be accessible via a time-series query tool, and the complete archive of webcam imagery will be available for examination of visual changes in volcanic activity over time. The Web site will also include background information and references concerning the 1983-present eruption, descriptions of monitoring tools, and resources for instructors. The goal of this project is to demonstrate the dynamic nature of the Earth, promote excitement about the process of scientific discovery, and inspire the next generation of Earth scientists. To encourage use of the Web site, a workshop will be held in mid-2010 to develop curricula for various levels of college and university courses.

  16. Seismological evidence for an along-axis hydrothermal flow at the Lucky Strike hydrothermal vents site

    NASA Astrophysics Data System (ADS)

    Rai, A.; Wang, H.; Singh, S. C.; Crawford, W. C.; Escartin, J.; Cannat, M.

    2010-12-01

    Hydrothermal circulation at ocean spreading centres plays fundamental role in crustal accretion process, heat extraction from the earth and helps to maintain very rich ecosystem in deep Ocean. Recently, it has been suggested that hydrothermal circulation is mainly along the ridge axis at fast spreading centres above along axis melt lens (AMC). Using a combination of micro-earthquake and seismic reflection data, we show that the hydrothermal circulation at the Lucky Strike segment of slow spreading Mid-Atlantic Ridge is also along axis in a narrow (~1 km) zone above a wide (2-3 km) AMC. We find that the seismicity mainly lies above the seismically imaged 3 km wide 7 km long melt lens at 3.2 km depth. We observe a vertical plume of seismicity above a weak AMC reflection just north of the hydrothermal vent fields that initiates just above the AMC and continues to the seafloor. This zone is collocated with active rifting of the seafloor in the neo-volcanic zone. Beneath the hydrothermal vents sites, where a strong melt lens is imaged, the seismicity initiates at 500 m above the AMC and continues to the seafloor. Just south of the hydrothermal field, where the AMC is widest and strongest, the seismicity band lies 500 m above the melt lens in a 800 m thick zone, which does not continue to the seafloor. The presence the weak melt lens reflection could be due to a cooled and crystallised AMC (mush) that permits the penetration of hydrothermal fluids down to the top of the AMC indicated by seismicity plume and might be the in-flow zone for hydrothermal circulation. The strong AMC reflection could be due to fresh supply of melt in the AMC (pure melt), which has pushed the cracking front 500 m above the AMC. Beneath the hydrothermal fields, the strong AMC reflection and seismicity 500 above the AMC to the seafloor could represent cracking along the up-flow zone. The 800 m thick zone of seismicity above the pure melt zone could be the zone of hydrothermal cracking zone. We do not observe any seismicity along the main bounding faults. These results suggest that the hydrothermal flow is mainly along the ridge axis in a narrow zone above the AMC, even when the AMC only 7 km long.

  17. Hydrologic and geochemical monitoring in Long Valley Caldera, Mono County, California, 1985

    USGS Publications Warehouse

    Farrar, C.D.; Sorey, M.L.; Rojstaczer, S.A.; Janik, C.J.; Winnett, T.L.; Clark, M.D.

    1987-01-01

    Hydrologic and geochemical monitoring, to detect changes caused by magmatic and tectonic processes in the Long Valley caldera has continued through 1985. The monitoring included the collection of the following types of data: chemical and isotopic composition of water and gases from springs, wells, and steam vents; temperatures in wells, springs, and steam vents; flow rates of springs and streams; water levels in wells; and barometric pressure and precipitation at several sites. In addition, reservoir temperatures for the geothermal system were estimated from computations based on chemical geothermometers applied to fluid samples from wells and springs. Estimates of thermal water discharged from springs were made on the basis of boron and chloride fluxes in surface waters for selected sites in the Casa Diablo area and along the Mammoth-Hot Creek drainage. These data are presented in tables and graphs. The Long Valley area was relatively quiescent throughout 1985 in terms of geodetic changes and seismic activity. As a consequence , the hydrologic system varied mainly in response to seasonal influences of temperature, atmospheric pressure, and precipitation. However, spring flows near Casa Diablo were influenced by pumping at the geothermal production well field nearby. (Author 's abstract)

  18. 40 CFR Table 7 to Subpart Jjj of... - Group 1 Batch Process Vents and Aggregate Batch Vent Streams-Monitoring, Recordkeeping, and...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... collected—PR. d,e Carbon Adsorber f a. Total regeneration steam flow or nitrogen flow, or pressure (gauge or absolute) during carbon bed regeneration cycle(s), and 1. Record the total regeneration steam flow or nitrogen flow, or pressure for each carbon bed regeneration cycle.2. Record and report the total...

  19. 40 CFR Table 6 to Subpart U of... - Group 1 Batch Front-End Process Vents and Aggregate Batch Vent Streams-Monitoring, Recordkeeping...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... collected—PR. d,e Carbon adsorber f a. Total regeneration steam flow or nitrogen flow, or pressure gauge or absolute) during carbon bed regeneration cycle(s), and 1. Record of total regeneration steam flow or nitrogen flow, or pressure for each carbon bed regeneration cycle. 2. Record and report the total...

  20. 40 CFR Table 6 to Subpart U of... - Group 1 Batch Front-End Process Vents and Aggregate Batch Vent Streams-Monitoring, Recordkeeping...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... collected—PR. d,e Carbon adsorber f a. Total regeneration steam flow or nitrogen flow, or pressure gauge or absolute) during carbon bed regeneration cycle(s), and 1. Record of total regeneration steam flow or nitrogen flow, or pressure for each carbon bed regeneration cycle. 2. Record and report the total...

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