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1

Reported tailings dam failures  

Microsoft Academic Search

A detailed search and re-evaluation of the known historical cases of tailings dam failure was carried out. A corpus of 147 cases of worldwide tailings dam disasters, from which 26 located in Europe, was compiled in a database. This contains six sections, including dam location, its physical and constructive characteristics, actual and putative failure cause, sludge hydrodynamics, socio-economical consequences and

M. Rico; G. Benito; A. R. Salgueiro; A. D ´ õez-Herrero; H. G. Pereira

2008-01-01

2

Floods from tailings dam failures  

Microsoft Academic Search

This paper compiles the available information on historic tailings dam failures with the purpose to establish simple correlations between tailings ponds geometric parameters (e.g., dam height, tailings volume) and the hydraulic characteristics of floods resulting from released tailings. Following the collapse of a mining waste dam, only a part of tailings and polluted water stored at the dam is released,

M. Rico; G. Benito; A. Díez-Herrero

2008-01-01

3

Geo-Seismic Environmental Aspects Affecting Tailings Dams Failures  

Microsoft Academic Search

Seismic performance evaluations of tailings dams are essential for characterizing the geo- environmental risks posed by these earthen structures, which should include the geotechnical hazards implied by slope instability failure, free board loss and the potential release of contaminants. The observed damage is more important when liquefaction occurs on the dam body and foundation, which often leads to cracking, settlements,

Juan M. Mayoral; Miguel P. Romo

2008-01-01

4

Safety of Tailings Dams  

NSDL National Science Digital Library

Contains information on different aspects of tailings dams; tailings dam properties, disasters, failure modes, slurry waves, stability analysis, and safe tailings disposal. Also includes a slope stability calculator and a tailings flow slide calculator.

2008-08-25

5

Reported tailings dam failures. A review of the European incidents in the worldwide context.  

PubMed

A detailed search and re-evaluation of the known historical cases of tailings dam failure was carried out. A corpus of 147 cases of worldwide tailings dam disasters, from which 26 located in Europe, was compiled in a database. This contains six sections, including dam location, its physical and constructive characteristics, actual and putative failure cause, sludge hydrodynamics, socio-economical consequences and environmental impacts. Europe ranks in second place in reported accidents (18%), more than one third of them in dams 10-20 m high. In Europe, the most common cause of failure is related to unusual rain, whereas there is a lack of occurrences associated with seismic liquefaction, which is the second cause of tailings dam breakage elsewhere in the world. Moreover, over 90% of incidents occurred in active mines, and only 10% refer to abandoned ponds. The results reached by this preliminary analysis show an urgent need for EU regulations regarding technical standards of tailings disposal. PMID:17854989

Rico, M; Benito, G; Salgueiro, A R; Díez-Herrero, A; Pereira, H G

2007-07-22

6

The tailings dam failures in Maramures county, Romania and their transboundary impacts on the river systems  

Microsoft Academic Search

\\u000a The tailings dam failures that occurred in January and March 2000 in Maramures County northwest Romania, discharged contaminated\\u000a water and sediment directly into river systems that drain into the Tisa River, a major tributary of the River Danube. To ascertain\\u000a the long-term impacts of these spills, a survey of metal contamination in surface water, river channel and floodplain sediment\\u000a in

Paul A. Brewer; Mark G. Macklin; Dan Balteanu; Tom J. Coulthard; Basarab Driga; Andy J. Howard; Graham Bird; Sorin Zaharia; Mihaela Serban

7

Remediation of Tailings Dams  

Microsoft Academic Search

\\u000a Tailings are a waste product of mining activities. The ore is crushed in processing to a size less than 0.1 to 1.0 mm, the\\u000a metal content is removed, and the remaining product is called tailings. Normally, the tailings will be pumped as slurry to\\u000a a sedimentation pond that is surrounded by dams and, sometimes, natural heights that form a tailings

A. G. Benckert

8

A Tragic Disaster Caused by the Failure of Tailings Dams Leads to the Formation of the Stava 1985 Foundation  

Microsoft Academic Search

This paper summarizes the dynamics and causes of the Stava disaster, and highlights some risky design procedures that led to the 19 July 1985 tailings dam failure. It then presents the “Stava 1985 Foundation”, which was formed to focus attention on such risks and to strengthen the culture of respect for human lives and safety.

Onofrio Sammarco

2004-01-01

9

River system recovery following the Nova?-Ro?u tailings dam failure, Maramure? County, Romania  

Microsoft Academic Search

The River Vi?eu catchment in Maramure? County, northwestern Romania, has a long history of base and precious metal mining. Between 1994 and 2003 waste from mining activity at Baia Bor?a was stored in the Nova?-Ro?u tailings pond in the upper Vi?eu catchment. However, in March 2000, the tailings dam failed releasing approximately 100,000m3 of contaminated water and 20,000t of mineral-rich

Graham Bird; Paul A. Brewer; Mark G. Macklin; Dan Balteanu; Mihaela Serban; Basarab Driga; Sorin Zaharia

2008-01-01

10

Trends in Tailing Dam Safety  

Microsoft Academic Search

Recent releases of tailing effluents and solids from containment facilities around the world, including Mary Spruitt (1994), Omai (1995) and Marcopper (1996), have heightened awareness that risks associated with tailing containment must be fully addressed during all phases of a facility life. Recent studies by independent international organizations (United Nations Environment Programme (UNEP), 1996; United Stated Committee on Large Dams

Iain G. Bruce; Clint Logue; Lori-Ann Wilchek

11

Detecting dam failures  

SciTech Connect

This article describes efforts by Southern California Edison to meet Federal Energy Regulatory Commission requirements for unattended dam monitoring against failure. The topics include a description of the two dam systems, monitoring system design and operation including warning sirens for remote camping areas, and installation of the systems.

Knarr, C.M.; Barker, T.J.; McKenery, S.F. (Southern California Edison Co., Rosemead, CA (United States))

1994-06-01

12

The long term fate and environmental significance of contaminant metals released by the January and March 2000 mining tailings dam failures in MaramuresCounty, upper Tisa Basin, Romania  

Microsoft Academic Search

In January and March 2000 two tailings dam failures in MaramuresCounty, northwest Romania, resulted in the release of 200,000 m3 of contaminated water and 40,000 tonnes of tailings into tributaries of the Tisa River, a major tributary of the Danube. The high concentrations of cyanide and contaminant metals released by these dam failures resulted in pollution and fish deaths not

Paul A. Brewer; Tom J. Coulthard; Andy J. Howard; Sorin Zaharia

13

Design of Dams for Mill Tailings.  

National Technical Information Service (NTIS)

The report describes tailings disposal problems at mines throughout the United States in order to identify design principles that can be applied to all types of dams for mill tailings. The circular reviews computer programs for stability analysis and phre...

C. D. Kealy R. L. Soderberg

1969-01-01

14

Stability analysis of a copper tailings dam via laboratory model tests: A Chinese case study  

Microsoft Academic Search

The upstream method is a popular method for raising tailings dams. Currently in China there are more than 12,000 tailings impoundments and almost 95% of them use the upstream method for the construction of the dam. Statistical data has shown that the tailings impoundment is one of the main sources of risk in the mining industry. Failures of tailings impoundments

Guangzhi Yin; Guangzhi Li; Zuoan Wei; Ling Wan; Guohong Shui; Xiaofei Jing

2011-01-01

15

Survey of Radionuclide Distributions Resulting from the Church Rock, New Mexico, Uranium Mill Tailings Pond Dam Failure  

SciTech Connect

An intensive site survey and on-site analysis program were conducted to evaluate the distribution of four radionucliGes in the general vicinity of Gallup, New Mexico, subsequent to the accidental breach of a uranium mill tailings pond dam and the release of a large quantity of tailings pond materials. The objective of this work was to determine the distribution and concentration levels of {sup 210}Pb, {sup 226}Ra, {sup 230}Th, and {sup 238}U in the arroyo that is immediately adjacent to the uranium tailings pond (pipeline arroyo) and in the Rio Puerco arroyo into which the pipeline arroyo drains. An intensive survey between the United Nuclear Corporation (UNC) Church Rock Mill site and the New Mexico-Arizona state border was performed. Sampling locations were established at approximately 500-ft intervals along the arroyo. During the weeks of September 24 through October 5, 1979, a series of samples was collected from alternate sampling locations along the arroyo. The purpose of this collection of samples and their subsequent analysis was to provide an immediate evaluation of the extent and the levels of radioactive contamination. The data obtained from this extensive survey were then compared to action levels which had been proposed by the Nuclear Regulatory Commission and were adapted by the New Mexico Environmental Improvement Division (NMEID) for {sup 230}Th and {sup 226}Ra concentrations that would require site cleanup. The Pacific Northwest Laboratory/Nuclear Regulatory Commission mobile laboratory van was on-site at the UNC Church Rock Mill from September 22, 1979, through December 13, 1979, and was manned by one or more PNL personnel for all but four weeks of this time period. Approximately 1200 samples associated with the Rio Puerco survey were analyzed 1n the laboratory. An additional 1200 samples related to the Rio Puerco cleanup operations which the United Nuclear Corporation was conducting were analyzed on-site in the mobile laboratory. The purpose of these analyses was to determine the effectiveness of the cleanup operations that were ongoing and to evaluate what additional cleanup would be required. This on-site analysis of radioactive contamination constituted the principal task of this project, with the identification of those portions of the arroyo exceeding the NMEID proposed cleanup criteria being the major output. Additiond1 tasks included an evaluation of the initial soil sampling scheme (letter from T. Wolff [NMEID] to J. Abiss [UNC]. oated September 25, 1979) and the proposed NMEID verification sampling scheme (letter from T. Buhl [NMEID] to H. Miller [NRC]. dated April 23, 1980).

Weimer, W. C.; Kinnison, R. R.; Reeves, J. H.

1981-12-01

16

The internet of things (IOT) and cloud computing (CC) based tailings dam monitoring and pre-alarm system in mines  

Microsoft Academic Search

Tailings disposal is a significant consideration for the mining industry, with the majority of the ore processed in most mining operations ending up as tailings. Several tailings dam failure accidents have occurred during the past few years and mine tailings dam failures, which are disastrous with the serious damage and the loss of lives, are occurring at relatively high rates.

Enji Sun; Xingkai Zhang; Zhongxue Li

17

MINE TAILINGS DAMS: WHEN THINGS GO WRONG  

Microsoft Academic Search

Mine tailings impoundment failures continue to occur at unacceptable rates. The worldwide mining industry has experienced roughly one significant impoundment failure per year over the past 30 years. Many of these failure events have resulted in massive damage, severe economical impact and, in several cases, loss of life. A tailings impoundment failure case history database has been developed. In addition

Michael Davies; Todd Martin; Peter Lighthall

18

Implications of Earthquakes on the Stability of Tailings Dams  

Microsoft Academic Search

Analyses of earthquakes show the need of detailed assessment of the vulnerability different industry sectors. As part of this assessment implication of earthquakes for the mining industry and especially the stability of the tailings ponds was investigated. Based on the serious dam failures a decision tree was developed to categorize the loss scenarios. To test the decision tree and to

Tobias Rudolph; Wilhelm G. Coldewey

19

Groundwater pollution due to a tailings dam  

Microsoft Academic Search

In 1982, the Oman Mining Company (OMC) commenced copper mining and smelting operations in the area of Sohar (Wadi Suq), Sultanate of Oman. Seawater was used for mining operations until 1993. During this period, 11 million tonnes of tailings had been deposited behind an unlined tailings dam. This has resulted in a major groundwater pollution problem.This paper presents results from

R. S Sharma; T. S Al-Busaidi

2001-01-01

20

Risk analysis for seismic design of (tailings dams)  

SciTech Connect

Probabilistic seismic risk analysis is a promising method for evaluating design options and establishing seismic design parameters. However, there have been few examples in the literature to guide practitioners in its use. (This paper demonstrates the value of risk analysis for mine tailings dams and provides a case-history application for a seismically active portion of Nevada. Risk analysis provided the basis for selecting among design options having varying liquefaction resistance, and for establishing input parameters for dynamic analysis. Ranges are presented for the quantity and cleanup cost of tailings released in seismic failures to aid in determining expected failure consequences. It is shown that for many tailings dams, accepted lifetime failure probabilities of a few percent may provide a reasonable basis for probabilistic determination of seismic design criteria.)

Vick, S.G.; Atkinson, G.M.; Wilmot, C.I.

1985-07-01

21

3. VIEW OF WEST TAILING DAM, LARGE TANK, AND TAILING, ...  

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

3. VIEW OF WEST TAILING DAM, LARGE TANK, AND TAILING, LOOKING NORTHEAST. A SIX-FOOT SCALE IS LOCATED AGAINST WALL ON LEFT. PURPOSE OF TANK IS UNKNOWN, BUT APPEARS TO HAVE FALLEN FROM ITS ORIGINAL LOCATION AT THE MILL SITE, UP AND TO THE RIGHT OF THIS VIEW. - Skidoo Mine, Park Route 38 (Skidoo Road), Death Valley Junction, Inyo County, CA

22

Design of tailing dam using red mud  

NASA Astrophysics Data System (ADS)

Red mud, waste industrial product from aluminum industries produced approximately 75 million tonnes every year with less than half of this is used. Storage of this unutilized red mud takes vast tracts of usable land and pollutes, land, air and water. Construction of high embankments, under passes, flyovers, tailing dams uses vast tract of natural resources (top soil) is also matter of concern as its takes thousands of years to form the natural soil. This paper discusses use of red mud for construction of tailing dam based on laboratory findings and finite element analysis. The geotechnical properties such as plasticity, compaction, permeability, shear strength characteristics and dispersion of red mud are presented. Stability and seepage analysis of tailing dams as per finite element analysis using the above geotechnical parameters is presented.

Rout, Subrat K.; Sahoo, Tapaswini; Das, Sarat K.

2013-06-01

23

Design of Tailings Dams and Impoundments  

Microsoft Academic Search

The state of practice for tailings dam and impoundment design is summarized. The design process, which embraces construction, operational and closure issues together with requisite technical aspects, has evolved over the past several decades though the engineering principles have remained the same. The design process has evolved to meet the demands of a regulatory environment that has become increasingly stringent

Michael P. Davies; Peter C. Lighthall; Steve Rice; Todd E. Martin

24

Fundamental aspects of the flow characteristics of liquefied mine tailings dams  

Microsoft Academic Search

A characteristic common to most tailings dam failures caused by earthquakes or excessive rain storm is that the tailings tend to liquefy and flow for substantial distances as a viscous fluid, with the potential for extensive damage to property and life. Failures of El Cobre, Chile (1965), Mochikoshi, Japan (1978), Aberfan, Wales (1966), Buffalo Creek, West Virginia (1972) are examples

Jeyapalan

1982-01-01

25

IMPACT PREDICTION OF THE REACTIVATION OF AN UNUSED TAILINGS DAM  

Microsoft Academic Search

A frequent occurrence in areas with a long history of mining is the reactivation of mine residue deposits. This paper presents an impact prediction study conducted for the reactivation of a gold tailings dam. Two phases of new tailings deposition are proposed. The objective of the study was to assess the potential impact on downstream groundwater quality. The tailings dam

TERRY HARCK; BERNADETTE AZZIE; CATRIONA COYLE; TALITA GERMISHUYSE; RAVI VADAPALLI; ALBERT VAN ZYL

26

Geological impact of some tailings dams in Sardinia, Italy  

Microsoft Academic Search

This article deals with the results of a survey carried out in Sardinia on both active and abandoned tailings dams, and we also discuss the geological impact of tailings dams of two mines: the Masua mine, a large syngenetic Pb-Zn deposit located in Cambrian limestones, and the Montevecchio mine, a Pb-Zn vein deposit near a Hercynian granite intrusion. The characteristics

Felice Di Gregorio; Raniero Massoli-Novelli

1992-01-01

27

RSNN-Based Instability Disaster Prediction of Tailings Dam  

Microsoft Academic Search

The instability disaster prediction model of tailings dam had been established, based on system analysis of the factors that caused the instability disaster of tailings dam, by selecting 6 prediction index, medium unit weight, cohesion, internal friction angle, slope angle, slope height and pore pressure ratio and combining with using theory of the rough set and neural network. First the

Keping Zhou; Shuna Li; Qingfa Chen; Rui Chen

2009-01-01

28

Environmentally safe design of tailing dams for the management of iron ore tailings in Indian context.  

PubMed

The need for the disposal of iron ore tailings in an enviornmentally firiendly manner is of great concern. This paper investigates the soil engineering properties for the construction of iron ore tailing dam, its foundation, construction materials and design data used for the construction analysis of the tailing dam. Geophysical investigations were carried out to establish the bedrock below the spillway. A computer programme taking into account the Swedish Slip Circle Method of analysis was used in the stability analysis of dam. It also focuses on the charactierstics of the tailings reponsible for the determination of optimum size of tailing pond for the containment of the tailings. The studies on the settling characteristics of tailings indicate much less area in comparison to the area provided in the existing tailing ponds in India. In the proposed scheme, it is suggested to provide an additional unit of sedimentation tank before the disposal of tailings to the tailing pond. PMID:17051916

Ghose, Mrinal K; Sen, P K

2005-10-01

29

National Dam Safety Program. Buick Mine Tailings Dam (MO 30162), White River Basin, Reynolds County, Missouri. Phase I Inspection Report.  

National Technical Information Service (NTIS)

Buick Mine Tailings Dam, Missouri Inventory Number 30162, was inspected. Buick Mine Tailings Dam is classified as a large dam based on its present height of 141 ft. The maximum storage capacity is approximately 19,300 ac-ft. The large dam classification c...

R. G. Berggreen L. M. Krazynski

1981-01-01

30

Primary vegetative growth on an old tailings dam, Zawar mines  

Microsoft Academic Search

Tailings containing toxic qualities of heavy metals are a potential source of pollution. Stabilisation by vegetative methods have been found the most effective. In an attempt to vegetate tailings dams it has been noted that while certain milky latex containing plants can be grown without any preconditioning of the soil, almost any plant can be grown after proper conditioning. However,

D. M. R. Sekhar; M. R. Jakhu

1983-01-01

31

Fundamental aspects of the flow characteristics of liquefied mine tailings dams  

SciTech Connect

A characteristic common to most tailings dam failures caused by earthquakes or excessive rain storm is that the tailings tend to liquefy and flow for substantial distances as a viscous fluid, with the potential for extensive damage to property and life. Failures of El Cobre, Chile (1965), Mochikoshi, Japan (1978), Aberfan, Wales (1966), Buffalo Creek, West Virginia (1972) are examples of such catastrophic incidents. In these four incidents more than 400 lives were lost, and the loss of property was approximately $200 million. In order to be able to assess the potential for damage in case of such a failure, it is necessary to predict the possible extent of flow slide movement. This paper discusses simple procedures for performing such analyses. Also, in order to illustrate the use of these analysis procedures in tailings dam design, two case histories are analyzed.

Jeyapalan, J.K.

1982-09-01

32

Geological impact of some tailings dams in Sardinia, Italy  

NASA Astrophysics Data System (ADS)

This article deals with the results of a survey carried out in Sardinia on both active and abandoned tailings dams, and we also discuss the geological impact of tailings dams of two mines: the Masua mine, a large syngenetic Pb-Zn deposit located in Cambrian limestones, and the Montevecchio mine, a Pb-Zn vein deposit near a Hercynian granite intrusion. The characteristics and metal content of material in the dams were analyzed. A high contamination of heavy metals (Pb, Zn, Cd, Cu) was found both in the soils and water of Rio Montevecchio, a stream draining the tailings dams and other mining operations in the area. The study indicates that a control plan to minimize heavy metal pollution must be drawn up for all mines of the area, whether active or abandoned.

di Gregorio, Felice; Massoli-Novelli, Raniero

1992-05-01

33

2. VIEW OF EAST TAILING DAM (FOREGROUND), LOOKING EAST SOUTHEAST ...  

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

2. VIEW OF EAST TAILING DAM (FOREGROUND), LOOKING EAST SOUTHEAST UP WASH TOWARD ORE BIN, OVERBURDEN, ADITS, AND ROAD SHOWN IN CA-290-1. MILL SITE IS UP AND TO THE RIGHT OF THIS VIEW. STANDARD FIFTY-GALLON DRUM IN FOREGROUND GIVES SCALE OF WALL. - Skidoo Mine, Park Route 38 (Skidoo Road), Death Valley Junction, Inyo County, CA

34

1. VIEW OF THE MILL TAILINGS FACING NORTHWEST. SEDIMENT DAM ...  

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

1. VIEW OF THE MILL TAILINGS FACING NORTHWEST. SEDIMENT DAM AND POND IN THE FOREGROUND, AND WATER PUMP (FEATURE B-25) ON THE LOWER RIGHT SIDE OF PHOTO. - Nevada Lucky Tiger Mill & Mine, East slope of Buckskin Mountain, Paradise Valley, Humboldt County, NV

35

Risk analysis for seismic design of (tailings dams)  

Microsoft Academic Search

Probabilistic seismic risk analysis is a promising method for evaluating design options and establishing seismic design parameters. However, there have been few examples in the literature to guide practitioners in its use. (This paper demonstrates the value of risk analysis for mine tailings dams and provides a case-history application for a seismically active portion of Nevada. Risk analysis provided the

Steven G. Vick; Gail M. Atkinson; Charles I. Wilmot

1985-01-01

36

Modeling the Seismic Response of Coal-Waste Tailings Dams  

Microsoft Academic Search

Coal is often processed near coal mines to remove some impurities before it is transported to its users. Each year, millions of tons of refuse are generated and need to be stored in the coal producing regions. A typical coal-waste storage facility is a tailings dam which includes an embankment made of coarse refuse and impoundment slurry of fine refuse.

Xiangwu Zeng; Jiaer Wu; Richard Rohlf

37

Compaction of Upstream Construction Tailings Dam Beaches Using Dozers  

Microsoft Academic Search

Upstream construction tailings dams in the oilsands mining industry rely on a compacted shell and beaches of non- liquefiable sand to contain the pond and internal loose beach deposits. Compaction energy to densify the sand in the shell is provided by dozers which densify the sand through the vibration of trafficking repeatedly across the sand surface, together with the downward

Scott Martens; Tyler Lappin

38

Rehabilitation of Tailings Dams on the Central Rand; Johannesburg  

Microsoft Academic Search

Underground mining on the Central Rand goldfield of the Witwatersrand basin south of Johannesburg has led to a number of environmental impacts of which the establishment of tailings dams is the most important. These mining residue deposits are impacting negatively on the environment and on social and economic development of the area. This is because of pollution and sterilization of

N. F. Mphephu

39

Investigation of environmental impacts of tailings dams  

Microsoft Academic Search

Mining has been one of the key sectors for industrialisation of the world for centuries. As the mining activities enlarge, the amount of waste materials readily increases. Storage of waste materials or tailings disposal has become a serious matter for the mining industry due to its enlargement especially for the last 30 years. During the beneficiation of valuable metals and

Safak Ozkan; Bedri Ipekoglu

2002-01-01

40

Estimation of the Variability of Tailings Dams Properties in Order to Perform Probabilistic Assessment  

Microsoft Academic Search

Dams are often used for storing mine tailings. These structures present failure mechanisms that can lead to major risks for\\u000a surrounding populations. In view to managing these risks, it is necessary to take a probabilistic approach in predicting their\\u000a behaviour. The application of such approaches is limited by the difficulty of obtaining experimental data to estimate the\\u000a variability of the

A. Gabriel Villavicencio; Pierre Breul; Claude Bacconnet; Daniel Boissier; A. Raúl Espinace

41

Application to monitoring of tailings dam based on 3D laser scanning technology  

NASA Astrophysics Data System (ADS)

This paper presented a new method of monitoring of tailing dam based on 3D laser scanning technology and gave the method flow of acquiring and processing the tailing dam data. Taking the measured data for example, the author analyzed the dam deformation by generating the TIN, DEM and the curvature graph, and proved that it's feasible to global monitor the tailing dam using 3D laser scanning technology from the theory and method.

Ren, Fang; Zhang, Aiwu

2011-05-01

42

Geochemical modeling of cyanide in tailing dam gold processing plant  

NASA Astrophysics Data System (ADS)

This research is aimed at investigating possible neutralization of cyanide in tailing dam of Muteh gold processing plant in Isfahan, Iran at various conditions such as pH and temperature using USEPA Visual MINTEQ geochemical model simulation. The model is based on geochemical equilibrium which uses the simultaneous solution of the non-linear mass action expressions and linear mass balance relationships to formulate and solve the multiple-component chemical equilibrium problems. In this study the concentration of aqueous species in tailing dam as an aqueous, solid and gaseous were used as input in the model. Temperature and pH variation were simulated. The results of the model indicated that cyanide may be complexes in 10 < pH < 5. In other pH values complexation is not important. The results also indicated that cyanide reduction mechanism in acidic pH and temperature above 30°C is due to cyanide acid formation which is vaporized.

Khodadadi, Ahmad; Monjezi, M.; Mehrpouya, H.; Dehghani, H.

2009-09-01

43

Geochemical modeling of cyanide in tailing dam gold processing plant  

Microsoft Academic Search

This research is aimed at investigating possible neutralization of cyanide in tailing dam of Muteh gold processing plant in\\u000a Isfahan, Iran at various conditions such as pH and temperature using USEPA Visual MINTEQ geochemical model simulation. The\\u000a model is based on geochemical equilibrium which uses the simultaneous solution of the non-linear mass action expressions and\\u000a linear mass balance relationships to

Ahmad Khodadadi; M. Monjezi; H. Mehrpouya; H. Dehghani

2009-01-01

44

Tailings dams stability analysis using numerical modelling of geotechnical and geophysical data  

NASA Astrophysics Data System (ADS)

Methods for monitoring seepage and detecting internal erosion are essential for the safety evaluation of embankment dams. Internal erosion is one of the major reasons for embankment dam failures, and there are thousands of large tailings dams and waste-rock dumps in the world that may pe considered as hotspots for environmental impact. In this research the geophysical survey works were performed on Cetatuia 2 tailings dam. Electrical resistivity imaging (ERI) method was able to detect spatially anomalous zones inside the embankment dam. These anomalies are the results of internal erosion phenomena which may progressing inside the dam and is difficult to detect by conventional methods. Data aquired by geophysical survey together with their interpretations were used in the numerical model for slope stability assessment. The final results show us the structural weakness induced by the presence of internal erosion elements especially for seismic loading case. This research methodology may be also available for tailings dam monitoring purposes. Electrical Rezistivity Imaging (ERI) was performed on Cetatuia 2 dam at the Uranium Milling Plant Feldioara, in order to map areas with lateral and vertical changes in resistivity. The electrodes are connected to an automated computer operated switch box that selects the 4 electrodes to be used. A computer controls the switch box and the measuring device, and runs a program that selects the electrodes, makes the measurement, and stores the measurement. For inversion processing procedures was used Res2Din software. The measured resistivity were plotted by the pseudo section contouring method. There are five resistivity pseudosections obtained from the Cetatuia 2 tailings dam during the october 2007 measurements. Four transversal profiles trans1 to trans4 are perpendicular to the berms and the longitudinal one long1 is placed along dam's crest. The high resistivities near the berms surfaces corresponds to unsaturated fill materials and the low resistivities near the crest correspond to water saturated material. The resistivities values greater then 80 ohm.m may be explained by some error obtained for that inversion model. Profiles trans3 and trans4 were measured on perpendicular directions to berm alignment and show two distinct zones. The upward low resistivities zone correspond to water saturated materials especially from the compacted clay dam's core and the downward high resistivities zone belongs to unsaturated fill materials. The boundary between high and low resistivity at the depth of about 5 to 7 meters shows the groundwater level. The continuation of the high resistivity zones towards the end of the profile trans3, which is different from other profiles is probably due to the presence of dry coarse materials in shallow depth correspondingly to sandy clay. The sand fractions from the clay matrix may be affected by internal erosional phenomena, due to seepage currents that overpassed the material critical gradient. In this case the relative high resistivities values were considered as a presumptive erosional pattern. This profile was considered for the slope stability finite element modelling. The profile long1 which is placed along dam's crest is the longest profiles and extends up to nearly 420 m. The boundary between high and low resistivity at the depth of about 4 to 8 meters shows the groundwater across the dam core. The central part of the profile (about meter 200) shows the same relative high resistivities that occurred on transversal profile trans3. Resistivity data was used for building the 3D electrical resistivity model. The water saturated materials have locations very close to dam's crest (resistivity values usually lower then 10 ohm.m) and on both dam's arms. The groundwater levels were confirmed by the piezometric measurements. Electrical Rezistivity Imaging method had the possibility to show the most important disturbant elements that in certain conditions may weak the dam's state of safety. This study considered the SSR (Shear Strength Reduction) technique for sl

Mihai, S.; Zlagnean, M.; Oancea, I.; Petrescu, A.

2009-04-01

45

Shaking Table Study to Investigate Failure Modes of Arch Dams.  

National Technical Information Service (NTIS)

Determining the stability of concrete dams using linear elastic finite element analyses can be very subjective when the results indicate nonlinear response. To reduce uncertainty associated with failure of concrete arch dams during an earthquake, large la...

T. Payne

2002-01-01

46

Physical Modeling of Marginally Stable Tailings Dams Using Centrifuge Simulation Techniques.  

National Technical Information Service (NTIS)

The stability of a marginally stable tailings dam is investigated using centrifuge simulations and flow and stability analyses. The centrifuge simulations are conducted on Sandia's large radius machine using tailings from a coal mine. Pore pressure measur...

H. J. Sutherland R. P. Rechard A. A. Heckes

1984-01-01

47

Physical modeling of marginally stable tailings dams using centrifuge simulation techniques  

Microsoft Academic Search

The stability of a marginally stable tailings dam is investigated using centrifuge simulations and flow and stability analyses. The centrifuge simulations are conducted on Sandia's large radius machine using tailings from a coal mine. Pore pressure measurements and photographic coverage of the phreatic surface permit the determination of the flow field developed in the dam. The simulations investigate the effects

H. J. Sutherland; R. P. Rechard; A. A. Heckes

1984-01-01

48

Safety Analysis of Seepage Control on the Tailing Dam of Ekou Iron Mine  

Microsoft Academic Search

The safety operation of tailing dam not only affects the normal production of mine, but also directly impacts on the people's lives and property as well as the ecological environment of downstream. Seepage is the most important factor for the safety of the tailing dam and the environment of the reservoir area, so it is necessary to control seepage strictly.

Shen Zhenzhong; Ma Ming; Xu Liqun; Gan Lei

2009-01-01

49

Trace elements contamination of soils around gold mine tailings dams at Obuasi, Ghana  

Microsoft Academic Search

This study investigated the issue of tailings dams as a potential source of trace elements contamination in soils at the Obuasi gold mine in Ghana. Soil samples taken from depths of up to 12 cm and within a radius of 400 m from the tailings dams (active and decommissioned), were analysed for As, Cu, Pb and Zn using atomic absorption

P. Antwi-Agyei; J. N. Hogarh; G. Foli

50

IMPROVEMENT IN THE STABILIY OF UPSTREAM METHOD PHOSPHATE TAILINGS DAMS WITH ROCK FILL SHELLS  

Microsoft Academic Search

Upstream method tailings dam c onstruction has been used throughout the world as an economic method for containm ent of slurry deposited tailin gs waste as hydraulic fill. These types of dams can be engineered to be stable in low seis micity zones of the world with c ontrol of the water pool away from the dam limits. Upstream method

ALLAN J. BREITENBACH

51

Physical modeling of marginally stable tailings dams using centrifuge simulation techniques  

SciTech Connect

The stability of a marginally stable tailings dam is investigated using centrifuge simulations and flow and stability analyses. The centrifuge simulations are conducted on Sandia's large radius machine using tailings from a coal mine. Pore pressure measurements and photographic coverage of the phreatic surface permit the determination of the flow field developed in the dam. The simulations investigate the effects of packing density and particle size distribution on the stability of a dam. The results illustrate that an increase in packing density can increase the stability of the embankment and that the addition of slurried fines to the embankment affects stability by changing the properties of the tailings used to construct the dam and by limiting the discharge of water from the reservoir through the dam. For the tailings studied here, the increase in packing density and fines increases the stability of the dam by changing the material properties of the tailings. However, these changes also restrict the flow through the embankment and thereby reduce the stability of the dam by raising the level of both the reservoir and the phreatic surface. The addition of fines into the reservoir dramatically lowers the position of the phreatic surface by restricting the flow of water into the dam. The effect of this decreased flow is to increase the stability of the embankment, if over-topping of the dam does not occur. 14 references, 15 figures, 2 tables.

Sutherland, H.J.; Rechard, R.P.; Heckes, A.A.

1984-02-01

52

ESTIMATING OVERALL RISK OF DAM FAILURE: PRACTICAL CONSIDERATIONS IN COMBINING FAILURE PROBABILITIES  

Microsoft Academic Search

With the move to a risk based approach to dam safety there has been a concomitant focus on estimating the probability of failure of dams. The majority of risk guidelines relate to the total probability of failure and therefore the individual probabilities estimated for different components and loading conditions need to be combined. In most cases the failure modes of

Peter Hill; David Bowles; Phillip Jordan; Rory Nathan

2004-01-01

53

Quasi-stable Slope-Failure Dams in High Asia  

NASA Astrophysics Data System (ADS)

Collapses of steep mountain slopes in the Himalaya, Karakoram, Pamir, Hindu Kush, and Tibetan Plateau are well known as a result of:(1) generally high seismicity in active tectonic areas; (2) prior deglaciation leaving undercut, unstable cliffs; (3) present-day debuttressing of rock cliffs by glacial down-wasting in conditions of global warming; and (4) degradation of permafrost cohesion and water-ice cementation in high mountain slopes. Landslide dams across mountain rivers are also well known worldwide and generally do not endure for long because of the common landslide-lake outburst floods (LLOF) whose discharge is commonly sufficiently large to remove much of the dam in a short time. A number of massive slope-failure dams in south High Asia, however, have endured for centuries and require explanations for the length of duration, whereas recent examples require robust assessment for better predictive hazard analysis. Three main factors contribute to longevity of slope-failure dams: (1) mega-rocks >15-30 m that inhibit dam failure in overflow breaches; (2) mega-porosity wherein incoming discharge to the landslide lake is balanced by subterranean water through-flow within the landslide dam; (3) impermeable clay fills caused by remobilization of prior lacustrine-dammed sediment that impart dam strength to allow lasting integrity for a time, and (4) climate-change induced lake-level lowering. Several examples of long-lived or unusually stable, slope-failure dams associated with pronounced structural/tectonic associations include: (1) Pangong Tso, Ladakh and Tibet; (2) Lake Shewa, Afghanistan; (3) Sarez Lake, Tajikistan; and (4) Lake Hunza, Pakistan. Pangong Tso and Lake Shewa were emplaced thousands of years ago and only Lake Shewa shows some instability of the dam front where percolating water maintains lake level but may be causing new slumping. Sarez Lake behind the Usoi landslide dam was emplaced by an earthquake in 1911 and maintains its level by seepage. Lake Hunza developed behind a new landslide dam in 2010 but remobilized lacustrine clay from a prior damming event and large blocks have maintained dam integrity in spite of overflow beginning 29 May 2010. Character and condition of landslide dams clearly controls whether LLOF or stability will prevail.

Shroder, J. F.

2010-12-01

54

Walter Bouldin Dam Failure and Reconstruction.  

National Technical Information Service (NTIS)

Walter Bouldin is one of several hydroelectric developments of Alabama Power Company. On February 10, 1975, an earth embankment section of Walter Bouldin Dam was breached, causing total evacuation of the forebay reservoir and rendering the 225-MW power pl...

1978-01-01

55

Laboratory study of the clogging process and factors affecting clogging in a tailings dam  

Microsoft Academic Search

Laboratory simulation of clogging in the Lixi tailings dam (Shaanxi Province, China) is urgently required because clogging is an important factor affecting the dam stability. This work firstly presents the results of ferrous iron oxidation experiments using buffer solution. The results indicate that the ferrous iron oxidation follows first order kinetics, and the oxidation process is strongly dependent on pH,

Jun Wu; Yanqing Wu; Jian Lu

2008-01-01

56

National Dam Inspection Program. Cornwall Tailings Dam (NDI Number PA-00597, DER Number 38-87), Susquehanna River Basin, Bernhard Creek, Lebanon County, Pennsylvania. Phase I Inspection Report.  

National Technical Information Service (NTIS)

Cornwall Tailings Dam was constructed by the Bethlehem Mine Corporation as a settlement basin for their tailings from a nearby iron ore mine operation. The mine was closed in 1977 and the facilities of the dam are presently not in use. At the time of insp...

1979-01-01

57

Close-range photogrammetric reconstruction of moraine dam failures  

NASA Astrophysics Data System (ADS)

Glacial Lake Outburst Floods (GLOFs) from moraine-dammed lakes represent a high magnitude, low frequency catastrophic glacio-fluvial phenomena, with the potential to cause significant damage to property and infrastructure in high-mountain regions. Detailed accounts of GLOF dynamics, in particular the initiation and propagation of dam breaching are extremely rare, owing to their occurrence in often remote, inaccessible areas, as well as the impracticalities associated with attempting to directly instrument such high magnitude, turbulent flows. In addition to the dearth of detailed, first-hand observations of dam failures, reconstruction of breaches and failure mechanisms derived from morphological evidence is hampered by the lack of high-quality, high-resolution DTMs of remote alpine areas. Previous studies have therefore resorted to the use of coarse resolution data products (SRTM, ASTER GDEM) to quantify characteristics of failure events, e.g. pre-flood lake volume, dam height/width, which may give rise to considerable uncertainty in related numerical simulations and assessments of downstream flood hazards. In this paper we employ a novel low-cost, close-range photogrammetric technique, termed 'Structure-from-Motion' (SfM) to provide detailed in-situ reconstructions of dam and valley topography for two moraine dam complexes which have produced historical GLOFs in the Khumbu Himal, Nepal. Requiring little more than a consumer-grade digital camera and suitable ground control for implementation, the resolution of the final data products are comparable to that obtained using ground-based or airborne LiDAR. These data facilitate the extraction of precise estimates of dam (and breach) geometry, volumes of water and sediment removed during the outburst events, and the downstream channel topography. We conclude by directly comparing such key metrics derived from low-resolution topographic datasets, with those acquired in situ using the SfM technique, and discuss the implications for the reconstruction of flood dynamics.

Westoby, M. J.; Brasington, J.; Glasser, N. F.; Hambrey, M. J.; Reynolds, J. M.

2012-04-01

58

The Environmental Impact of Cavnicului Valley Tailing Dams  

Microsoft Academic Search

Summary  In the Maramure? County, Cavnicului Valley there exist three tailing ponds belonging to the Cavnic Mining Company from C.N.M.P.N.\\u000a REMIN Baia Mare: Vr?nicioara, M?l?ini and Plopi?-R?chi?ele. This paper presents an analysis of the tailing ponds from a physical\\u000a and chemical stability point of view. The conclusion is that the tailing ponds of Vr?nicioara and Plopi?-R?chi?ele constitute\\u000a stability from a sliding

I. Bud; S. Duma; I. Denu?; I. Ta?cu

2007-01-01

59

The use of electroosmotic technique to improve safety conditions of abandoned tailing dams  

Microsoft Academic Search

A considerable number of tailing dams is scattered all over the abandoned mining districts of Sardinia. Some of them are actually huge and represent dangerous sources of contaminant diffusion in soil and underground water. Due to the volume of the basins, the best remediation strategy appears to be the construction of low permeability barriers both at the basin bottom and

Battista Grosso; Marco Cigagna; Pier Paolo Manca; Paolo Troncia

60

Design, construction and management of tailings storage facilities for surface disposal in China: case studies of failures.  

PubMed

Rapid development of China's economy demands for more mineral resources. At the same time, a vast quantity of mine tailings, as the waste byproduct of mining and mineral processing, is being produced in huge proportions. Tailings impoundments play an important role in the practical surface disposal of these large quantities of mining waste. Historically, tailings were relatively small in quantity and had no commercial value, thus little attention was paid to their disposal. The tailings were preferably discharged near the mines and few tailings storage facilities were constructed in mainland China. This situation has significantly changed since 2000, because the Chinese economy is growing rapidly and Chinese regulations and legislation require that tailings disposal systems must be ready before the mining operation begins. Consequently, data up to 2008 shows that more than 12 000 tailings storage facilities have been built in China. This paper reviews the history of tailings disposal in China, discusses three cases of tailings dam failures and explores failure mechanisms, and the procedures commonly used in China for planning, design, construction and management of tailings impoundments. This paper also discusses the current situation, shortcomings and key weaknesses, as well as future development trends for tailings storage facilities in China. PMID:23064963

Wei, Zuoan; Yin, Guangzhi; Wang, J G; Wan, Ling; Li, Guangzhi

2012-10-11

61

Dynamic decision making for dam-break emergency management - Part 2: Application to Tangjiashan landslide dam failure  

NASA Astrophysics Data System (ADS)

Tangjiashan landslide dam, which was triggered by the Ms = 8.0 Wenchuan earthquake in 2008 in China, threatened 1.2 million people downstream of the dam. All people in Beichuan Town 3.5 km downstream of the dam and 197 thousand people in Mianyang City 85 km downstream of the dam were evacuated 10 days before the breaching of the dam. Making such an important decision under uncertainty was difficult. This paper applied a dynamic decision-making framework for dam-break emergency management (DYDEM) to help rational decision in the emergency management of the Tangjiashan landslide dam. Three stages are identified with different levels of hydrological, geological and social-economic information along the timeline of the landslide dam failure event. The probability of dam failure is taken as a time series. The dam breaching parameters are predicted with a set of empirical models in stage 1 when no soil property information is known, and a physical model in stages 2 and 3 when knowledge of soil properties has been obtained. The flood routing downstream of the dam in these three stages is analyzed to evaluate the population at risk (PAR). The flood consequences, including evacuation costs, flood damage and monetized loss of life, are evaluated as functions of warning time using a human risk analysis model based on Bayesian networks. Finally, dynamic decision analysis is conducted to find the optimal time to evacuate the population at risk with minimum total loss in each of these three stages.

Peng, M.; Zhang, L. M.

2013-02-01

62

On the liquefaction failure of an earth dam  

SciTech Connect

In an effort to better assess the potential for sliding and liquefaction failure of earthen dams when subjected to earthquake loadings, a dynamic finite element approach focusing on these two failure mechanisms as well as on the vital role of the pore water pressure was undertaken. The constitutive response of the granular soil skeleton and its coupling with the fluid phase is formulated based on the Blot dynamic equations of motion. The constitutive model for the soil material was assumed to be linear with nonlinear terms included in the hysteretic damping terms. Despite the linear character of this theoretical model, one can still draw important conclusions regarding the stability and the liquefaction resistance of the cross-section. As an example, a hypothetical earth dam constructed over a saturated soil layer was considered. The steady state conditions of in-situ stress and pore pressure distributions in both the embankment and the foundation are evaluated and implemented in the stability and liquefaction criteria in conjunction with the dynamic analysis. The latter is carried out in the frequency domain and it reflects the response of the dam-foundation system to a seismic excitation. The computational aspect of the study is performed with finite element analysis. A transmitting boundary formulation for the two phase material was used to treat the infinite space problem. It is anticipated that the intensity of the earthquake input and certain soil properties have a profound effect on the failure susceptibility of the dam section. To address the uncertainties regarding the true values of such parameters, the analysis considered them parametrically.

Simos, N.; Reich, M. [Brookhaven National Lab., Upton, NY (United States); Costantino, C.J. [City Coll., New York, NY (United States). Dept. of Civil Engineering

1993-12-01

63

The potential for catastrophic dam failure at Lake Nyos maar, Cameroon  

Microsoft Academic Search

The upper 40 m of Lake Nyos is bounded on the north by a narrow dam of poorly consolidated pyroclastic rocks, emplaced during the eruptive formation of the Lake Nyos maar a few hundred years ago. This 50-m-wide natural dam is structurally weak and is being eroded at an uncertain, but geologically alarming, rate. The eventual failure of the dam

J. P. Lockwood; J. E. Costa; M. L. Tuttle; J. Nni; S. G. Tebor

1988-01-01

64

SEISMIC DESIGN OF LOS QUILLAYES TAILINGS DAMS IN CHILE DISEÑO SISMICO DE LA PRESA DE RELAVES LOS QUILLAYES IN CHILE  

Microsoft Academic Search

The paper describes the characteristics of Los Quillayes high tailings dam currently in operation at Los Pelambres copper mine in Chile and also includes a description of the selected design earthquake, the geotechnical characterization of tailings sand including cyclic strength, and the stability analysis originally carried out, both 2D and 3D, and other design considerations. A description of the current

Luis Valenzuela

65

Hydrogeophysical Modeling of Spatial and Temporal Salt Flushing of a Tailings Dam  

NASA Astrophysics Data System (ADS)

The Southwest Sand Storage (SWSS) is a large tailings dam located at Syncrude Canada’s Mildred Lake Operations, 40 km north of Fort McMurray, Alberta. It is 25 km2 in area, up to 40 m high and contains 300 million cubic metres of tailings sand. Sand was mounded and compacted to form a perimeter dyke that consists of 10 m high slopes separated by benches that are either “tipped-in” or “tipped-out”. The dyke is undrained and has an overall shallow slope of 10:1. The pond within the dam receives a slurry of sand tailings containing about 50% (by weight) of process affected water with high concentrations of sodium, calcium, sulphate and bicarbonate ions. The performance and viability of the reclaimed and vegetated landform following closure was questioned because the landscape might be negatively affected by the movement and discharge of process affected water through the dam. Some degree of temporal salt flushing from the percolation of rainwater was anticipated, but the vertical and the lateral extent of this flushing could not be modeled in the absence of detailed field measurements. To quantify the spatial and temporal flushing of salt at SWSS, two detailed monitoring transects were established. Nests of piezometers were installed along each transect to obtain point measurements for hydraulic head, electrical conductivity, soil-moisture and temperature. Water samples were periodically collected from the piezometers and from multi-level sampling ports distributed across the watertable. To supplement and complement the hydrogeologic data, Electrical Resistivity Tomography (ERT) surveys were conducted concurrently with hydrogeologic data collection in 2001, 2004, and 2008. Electrical conductivity difference plots (DmS/m) illustrate temporal salt flushing along the transects. The results indicate that the degree of flushing is closely associated with groundwater flow system scale, recharge rates, and dyke topography. Tipped-in (i.e., relatively flat) benches result in higher recharge rates and deeper water tables that are more favourable to salt flushing and to enhanced separation between plant roots and salty groundwater, as compared to tipped-out (i.e., slightly sloped) benches. Similarly, local flow systems established over the bench scale have a greater tendency for flushing compared to intermediate flow systems that may require centuries to flush. The conductivity difference plots closely match the hydrogeologic data, thus demonstrating the effectiveness of ERT as a non-invasive technique to model salt flushing within a tailings dam.

Cheema, T. J.; Mendoza, C. A.; Price, A.

2009-12-01

66

Quantitative and Qualitative Geospatial Analysis of a Probable Catastrophic Dam Failure  

NASA Astrophysics Data System (ADS)

Geospatial techniques were used in assessing inundation extents that would occur in the event of a catastrophic failure of Fort Peck dam. Fort Peck dam, located in Montana, USA has a spillway design which under dam failure the crest is expected to reach Williston a major economic hub in North Dakota in 1.4 days with a peak elevation of 1891 ft (576.377 m) msl (mean sea level). In this study, we address flooding extents and impacts on establishments with respect to a peak elevation of 1891 ft. From this study, we can unequivocally state that the City of Williston will be significantly impacted if Fort Peck dam fails with almost all critical needs, for example, gasoline stations, emergency facilities and grocery stores completely inundated. A secondary catastrophic event may be tied to the primary economic activity in Williston, that is, oil rigs of which most lie on the pathway of an inadvertent flood crest. We also applied a Discrete Fourier Transformation (DFT), and Lomb-Scargle normalized periodogram analyses and fitting of Fort Peck dam reservoir level fluctuations to gauge (a) likelihood of the dam overtopping, and (b) anatomic life span. Whereas we found that inasmuch as the dam could be considered stable by directly analyzing other dams that have failed, there is still a lower likelihood of it to fail at a 99-232 years range from construction. There was lack of concomitancy between overtopping and dam failure rates.

Oduor, P. G.; Stenehjem, J.

2011-12-01

67

ISSUES, RESOLUTIONS, AND RESEARCH NEEDS RELATED TO EMBANKMENT DAM FAILURE ANALYSIS  

Technology Transfer Automated Retrieval System (TEKTRAN)

This document is the proceedings of a 3-day workshop on "Issues, Resolutions, and Research Needs Related to Embankment Dam Failure Analysis," held in Oklahoma City, OK, June 26-28th, 2001. The workshop consisted of convening and facilitating a group of experts with respect to dam safety associated ...

68

Failure Dynamics of a Homogeneous Earth Dam Leaking Through a Fissure  

Microsoft Academic Search

Often, the catastrophic failure of a dam is due to water passing over the crest. The initial length of the overflow front may be from a few meters up to hundreds while the structure is undamaged or only a few meters if a fissure or breach is formed. There are several models for dam erosion through fissures, which use river

V. Kh. Davletshin

2001-01-01

69

National Dam Safety Program. Research Needs Workshop: Embankment Dam Failure Analysis.  

National Technical Information Service (NTIS)

One of the activities authorized by the Dam Safety and Security Act of 2002 is research to enhance the Nation's ability to assure that adequate dam safety programs and practices are in place throughout the United States. The Act of 2002 states that the Di...

2008-01-01

70

Sludge weathering and mobility of contaminants in soil affected by the Aznalcollar tailing dam spill (SW Spain)  

Microsoft Academic Search

As a result of the collapse of the Aznalcollar mine tailings dam, a large extension of the Guadiamar valley in SW Spain was covered with a layer of pyrite sludge. Although most of the sludge was removed, a small amount remains in the soil, constituting a potential source of water pollution. A column experiment was carried out in order to

C Domènech; C Ayora; J de Pablo

2002-01-01

71

Mineralogical characterization of tailing dams: incidence of abandoned mining works on soil pollution (Linares, Jaén)  

NASA Astrophysics Data System (ADS)

The metallogenic district of Linares-La Carolina (Jaén, Spain) consists of dyke mineralizations mainly of galena, accompanied by blende, chalcopyrite and barite. Associated to these abandoned mines, relatively extensive areas occupied by spoil heaps and tailing impoundments exist and constitute potential sources of soil pollution by metals and semimetals. In order to analyze the pollution potential of these mining wastes, we have carried out a mineralogical and geochemical study of seven tailing dams and surrounding soils in the area. The mineralogy of the samples was studied by x-ray diffraction (XRD) and scanning electron microscope (SEM). In addition, the total metal content of samples was determined by inductively coupled plasma mass spectrometry (ICP-MS) analysis. Samples were taken from the first 30 cm of the waste piles and soil deposits and white efflorescences were also obtained from the surface of the tailings. In all analyzed heaps, high to very high total contents in Pb (1220-22890 mg/kg), Zn (150-51280 mg/kg), Mn (2658-4160 mg/kg), Ba (1026-19610 mg/kg) and Fe (19400-138000 mg/kg) were observed. The concentrations for these same elements in the studied soils range from 527-9900 mg/kg for Pb, 27-1700 mg/kg for Zn, 506-2464 mg/kg for Mn, 2832-4306 for Ba and 8642-29753 mg/kg for Fe, and these figures indicate a contamination of the soils, according to the guidelines established by the Spanish law. The XRD and SEM results indicate that the tailings are primarily constituted by gangue of the exploited mineralization: quartz, calcite, ankerite, feldspars and phyllosilicates. They are inherited, primary mineral phases. Galena, also primary, appears in low proportion, as well as lepidocrocite, melanterite and cerussite, being these three last secondary minerals and indicating a certain remobilization of metal cations, especially lead and iron. On the other hand, quartz and phyllosilicates predominate in the soils, in which, in addition, is identified a little proportion of galena (primary mineral) and ferro-hexahydrite, also indicating mobilization of Fe. As regarding white surface blooms, they are formed mostly of magnesium sulphate with different hydration states. The morphology of these mineral precipitates reveals that they have been subject to cycle of washing and subsequent dehydration, which indicates that these phases present a great mobility in the environment, and they may be contributing to the transport of metals from the tailings into the surroundings soils.

de la Torre, M. J.; Hidalgo, C.; Rey, J.; Martínez, J.

2012-04-01

72

Scale amplification of natural debris flows caused by cascading landslide dam failures  

NASA Astrophysics Data System (ADS)

Debris flows are typically caused by natural terrain landslides triggered by intense rainfalls. If an incoming mountain torrent collapses a series of landslide dams, large debris flows can form in a very short period. Moreover, the torrent can amplify the scale of the debris flow in the flow direction. The catastrophic debris flows that occurred in Zhouqu, China, on 8 August 2010 were caused by intense rainfall and the upstream cascading failure of landslide dams along the gullies. In the wake of the incident, a field study was conducted to better understand the process of cascading landslide dam failures and the formation of debris flows. This paper looks at the geomorphic properties of the debris-flow gullies, estimates the peak flow discharges at different locations using three different methods, and analyzes the key modes (i.e., different landslide dam types and their combinations) of cascading landslide dam failures and their effect on the scale amplification of debris flows. The results show that five key modes in Luojiayu gully and two modes in Sanyanyu gully accounted for the scale amplification of downstream debris flows in the Zhouqu event. This study illustrates how the hazardous process of natural debris flows can begin several kilometers upstream as a complex cascade of geomorphic events (failure of landslide dams and erosion of the sloping bed) can scale to become catastrophic discharges. Neglecting recognition of these hazardous geomorphic and hydrodynamic processes may result in a high cost.

Cui, P.; Zhou, Gordon G. D.; Zhu, X. H.; Zhang, J. Q.

2013-01-01

73

Dams  

NSDL National Science Digital Library

National Geographic's Dams Web site offers an interactive investigation into the good and bad impacts of dam construction. Visitors choose to view a river system before, during, or after a dam is built. Then at each time interval they can click on various sections of the river and read a short description of what is happening there. For example, after the dam is built, the reservoir that is created upstream causes several hydrological problems such as loss of water from evaporation. Although the text provided on the site is somewhat lacking, the well-done graphics and interactivity make it worth a visit.

1997-01-01

74

Novel Method to Assess the Risk of Dam Failure  

Microsoft Academic Search

A new flexible, rapid and affordable risk assessment procedure was developed and verified for dams based on case studies in Scotland (UK) and the region of Baden (Germany). A database of six different sustainable flood retention basin (SFRB) types with varying flood control potential has been developed. In Scotland, there are a relatively high number of current and former large

Miklas Scholz; Qinli Yang

2011-01-01

75

Geomicrobiological and geochemical investigation of a pyrrhotite-containing mine waste tailings dam near Selebi-Phikwe in Botswana  

Microsoft Academic Search

An acid mine drainage (AMD) generating tailings dam consisting of waste from about 32 years of Ni-, Cu-, Zn- and Co-sulfidic ore processing near Selebi-Phikwe, Botswana, was investigated to quantify the AMD generation potential for developing a remediation strategy within the mine closure plan. The climate in the region is semiarid with an average annual temperature of 21 °C. The approximately 40 m

Axel Schippers; Dagmar Kock; Michael Schwartz; Michael E. Böttcher; Horst Vogel; Mike Hagger

2007-01-01

76

The potential for catastrophic dam failure at Lake Nyos maar, Cameroon  

NASA Astrophysics Data System (ADS)

The upper 40 m of Lake Nyos is bounded on the north by a narrow dam of poorly consolidated pyroclastic rocks, emplaced during the eruptive formation of the Lake Nyos maar a few hundred years ago. This 50-m-wide natural dam is structurally weak and is being eroded at an uncertain, but geologically alarming, rate. The eventual failure of the dam could cause a major flood (estimated peak discharge, 17000 m3/s) that would have a tragic impact on downstream areas as far as Nigeria, 108 km away. This serious hazard could be eliminated by lowering the lake level, either by controlled removal of the dam or by construction of a 680-m-long drainage tunnel about 65 m below the present lake surface. Either strategy would also lessen the lethal effects of future massive CO2 gas releases, such as the one that occurred in August 1986.

Lockwood, J. P.; Costa, J. E.; Tuttle, M. L.; Nni, J.; Tebor, S. G.

1988-09-01

77

INVESTIGATIONS INTO THE DEPTH AND RATE OF WEATHERING ON WITWATERSRAND GOLD TAILINGS DAM SURFACES AS KEY INFORMATION FOR LONG-TERM ARD RISK ASSESSMENTS 1  

Microsoft Academic Search

The generation of Acid Mine Drainage (AMD) from tailings dams of the Witwatersrand goldfields in South Africa, is arguably one of the main strategic environmental issues facing the gold mining industry and the South African government. Fine grained, sulfidic, tailings impoundments generate AMD through the diffusive ingress of oxygen into unsaturated pore spaces. Golder Associates conducted research on behalf of

Nico Bezuidenhout; Pierre D. S. Rousseau

78

Characteristics of Landslide Dam Failure by Practicing an Original Scale Field Experiment in Landow Creek, Huisun Experimental Forest, Taiwan  

NASA Astrophysics Data System (ADS)

This research built two artificial landslide dams, an original scale field experiment, in Landow creek, Huisun experimental forest on November 7th 2012. The purposes are to discuss characteristics of landslide dam failure, such as variations of velocity, development of the breach, and alteration of topography. We present four CCDs at upstream and downstream sides of two artificial landslide dams and used the Unmanned Aerial Vehicle (UAV) for monitoring and recording the processes of landslide dam failures. Besides, six water level sensors set up at upstream, and downstream sides of dams to identify inflow and outflow water level and determine the flow discharge; then, applying image judgments technique to determine the flow velocity and direction. Moreover, 3D LiDar scanner used to analyze the river morphology before and after the experiment. Landslide dam failure proceeds with three steps, pipping, turning into retrogressive erosion, and overtopping; however, overtopping dominates the most phenomenon in this experiment. During the impoundment filling, the downstream slope of landslide dam tends to steep as the retrogressive erosion occurs. After dam failure, the impoundment filled with sedimentary deposits; in addition, the original downstream main channel develops into many new flow paths and becomes braided river morphology. The momentary velocity of dam outbreak was nearly three times the inflow velocity; then the momentary discharge from the first failed dam to second dam was over more than 50 times the inflow discharge. The sediment concentration was inversely proportional to time at both upstream and downstream side due to the armor layer decreased. There are two outburst breaches processes, V and U types. The breaches development of two dams were both from V to U type, and vertical degradation to horizontal extension. The first breach dimension and the impoundment volume are both smaller than the second dam; hence we assumed that the breach dimension and impoundment volume have a significant correlation. The research results could provide better analyzing landslide dam hazards.

Chen, Su-Chin; Hsu, Tzu-Yang; Chao, Yi-Chiung

2013-04-01

79

The impact of tailings dam spills and clean-up operations on sediment and water quality in river systems: the R??os Agrio–Guadiamar, Aznalcóllar, Spain  

Microsoft Academic Search

The Aznalcóllar tailings dam at Boliden Apirsa's Aznalcóllar\\/Los Frailes Ag–Cu–Pb–Zn mine 45 km west of Seville, Spain, was breached on 25 April 1998, flooding approximately 4600 hectares of land along the R??os Agrio and Guadiamar with approximately 5.5 million m3 of acidic water and 1.3×106 m3 of heavy metal-bearing tailings. Most of the deposited tailings and approximately 4.7×106 m3 of

Karen A Hudson-Edwards; Mark G Macklin; Heather E Jamieson; Paul A Brewer; Tom J Coulthard; Andy J Howard; Jon N Turner

2003-01-01

80

Tailings dam seepage at the rehabilitated Mary Kathleen uranium mine, Australia  

Microsoft Academic Search

This study reports on the seepage of metals, metalloids and radionuclides from the Mary Kathleen uranium mill tailings repository. Since rehabilitation in the 1980s, the capped tailings have developed a stratified hydrochemistry, with acid (pH 3.7), saline, metal-rich (Fe, Mn, Ni, U±As, Pb, Zn), oxygenated (1.05 mg L?1 DO), radioactive waters in the upper tailings pile and near-neutral pH (pH

B. G. Lottermoser; P. M. Ashley

2005-01-01

81

Electrodialytic remediation of copper mine tailings  

Microsoft Academic Search

Mining activities in Chile have generated large amounts of solid waste, which have been deposited in mine tailing impoundments. These impoundments cause concern to the communities due to dam failures or natural leaching to groundwater and rivers.This work shows the laboratory results of nine electrodialytic remediation experiments on copper mine tailings. The results show that electric current could remove copper

Henrik K. Hansen; Adrián Rojo; Lisbeth M. Ottosen

2005-01-01

82

Combination of sequential chemical extraction and modelling of dam-break wave propagation to aid assessment of risk related to the possible collapse of a roasted sulphide tailings dam  

Microsoft Academic Search

The Sotiel–Coronada abandoned mining district (Iberian Pyrite Belt) produced complex massive sulphide ores which were processed by flotation to obtain Cu, Zn and Pb concentrates. The crude pyrite refuses were roasted for sulphuric acid production in a plant located close to the flotation site, and waste stored in a tailing dam. The present study was focused on the measurements of

Rafael Pérez-López; Reinaldo Sáez; Antonio M. Álvarez-Valero; José Miguel Nieto; Gaetano Pace

2009-01-01

83

Phytostabilisation of tailing dams: a quantification of physiological and biological responses in plants.  

PubMed

Effect of unamended and variously amended tailings of Rajpura-Dariba mines, Udaipur, India was studied on certain physiological and biochemical responses of plants. Plants grown in unamended tailings, showed reduction in shoot-root length, shoot-root dry weight, chlorophyll content and an increase in total phenol contents and peroxidase activity. Ameliorations resulted in an increase in growth and chlorophyll contents, a decrease in total phenol contents and reduction in peroxidase activity in the test plants. PMID:16649623

Sharma, A; Aery, N C

2004-10-01

84

Evaluation of heavy metal bio-availability from Almagrera pyrite-rich tailings dam (Iberian Pyrite Belt, SW Spain) based on a sequential extraction procedure  

Microsoft Academic Search

The beginning of polymetallic sulphide ore exploitation at Almagrera, Iberian Pyrite Belt, SW Spain, has been dated back to pre-Roman times; mining activity lasted until 2001 when it was definitely halted. The Almagrera sulphide tailings dam was built at the Sotiel–Coronada mine, where Cu, Zn and Pb concentrates were obtained by flotation processes, and sulphide (mainly pyrite) wastes formed. The

Antonio M. Álvarez-Valero; Reinaldo Sáez; Rafael Pérez-López; Joaquín Delgado; José M. Nieto

2009-01-01

85

Comparison of Failure Modes from Risk Assessment and Historical Data for Bureau of Reclamation Dams. Dam Safety Research Report.  

National Technical Information Service (NTIS)

In the summer of 1997, the Bureau of Reclamation Dam Safety Office funded a student summer sabbatical to review initial studies of Risk Analysis of various dams. Two major questions were addressed: (1) Are risk analyses producing consistent results from t...

J. Tatalovich

1997-01-01

86

Potential Flood Elevations and Economic Losses after a Catastrophic Dam Failure-- Remote Sensing Lesson  

NSDL National Science Digital Library

This remote sensing lesson from iGETT uses the example of flood elevations and a potential dam failure to give students experience using ArcGIS, ENVI and HAZUS-MH technologies. The lesson uses GIS and remote sensing technologies in the context of emergency preparedness and response planning. This lesson from iGETT includes a learning unit summary, instructor and student guides, support documents and a series of data files. A quick, free registration is required to view or download any of the materials.

2012-03-06

87

Ion mobility based on column leaching of South African gold tailings dam with chemometric evaluation  

Microsoft Academic Search

New column leaching experiments were designed and used as an alternative rapid screening approach to element mobility assessment. In these experiments, field-moist material was treated with an extracting solution to assess the effects of acidification on element mobility in mine tailings. The main advantage of this version of column leaching experiments with partitioned segments is that they give quick information

Ewa M Cukrowska; Koovila Govender; Morris Viljoen

2004-01-01

88

Sediment quality in Rio Guadiamar (SW, Spain) after a tailing dam collapse: contamination, toxicity and bioavailability.  

PubMed

An integrated assessment of sediment quality in the Guadiamar River after a mining spill was conducted. The concentration of different metals and other conventional parameters were measured in sediments located along the river. Four sediment toxicity tests (Hyalella azteca 28-day survival and growth test; Chironomus riparius 10-day survival and growth test; Hexagenia spp. 21-day survival and growth test; and Tubifex tubifex 28-day reproduction and survival test) were carried out to determine the effects associated with the accidental spill. The geochemical fractions of 6 metals (Fe, Mn, Zn, Cu, Pb, and Cd) were determined to establish the bioavailability of the metals. The relationship found in the concentrations of metals associated with the mobile fractions of the sediments in the sites studied is similar to the toxic mud from tailing pond and confirms that the toxic effects are associated with the metals Zn and Cd originating from the spill. PMID:16820209

Riba, Inmaculada; Delvalls, T Angel; Reynoldson, Trefor B; Milani, Danielle

2006-07-03

89

REPORT ON THE OUTCOMES OF A WORKSHOP ON ISSUES, RESOLUTIONS, AND RESEARCH NEEDS RELATED TO EMBANKMENT DAM FAILURE ANALYSES  

Technology Transfer Automated Retrieval System (TEKTRAN)

This paper summarizes the purpose, methodology, and outcomes of the June 2001 USDA/FEMA Workshop on Issues, Resolutions, and Research Needs Related to Embankment Dam Failure Analysis held in Oklahoma City, OK. The purpose of this workshop was to determine state of the practice, identify short-term ...

90

Cardiomyopathy and right-sided congestive heart failure in a red-tailed hawk (Buteo jamaicensis).  

PubMed

A 15-year-old female red-tailed hawk (Buteo jamaicensis) was evaluated because of dyspnea, anorexia, and coelomic distension. Diagnostic imaging results confirmed severe coelomic effusion and revealed a markedly dilated right ventricle. The diagnosis was right-sided congestive heart failure. Results of measurements of vitamin E, selenium, lead, zinc, and cardiac troponin levels were normal or nondiagnostic. The hawk was treated with furosemide, antifungal and antimicrobial agents, and supplemental fluids and oxygen, but euthanasia was elected because of the poor prognosis and the practical difficulties associated with intensive case management. To our knowledge, this is the first described case of cardiomyopathy and congestive heart failure in a captive red-tailed hawk. PMID:21657185

Knafo, S Emmanuelle; Rapoport, Gregg; Williams, Jamie; Brainard, Benjamin; Driskell, Elizabeth; Uhl, Elizabeth; Crochik, Sonia; Divers, Stephen J

2011-03-01

91

National Dam Safety Program. Old Mines Tailings Dam (MO 30706), Mississippi - Kaskaskia - St. Louis Basin, Washington County, Missouri. Phase I Inspection Report.  

National Technical Information Service (NTIS)

The purpose of the inspection was to assess the general condition of the dam with respect to safety. The assessment was based on an evaluation of the available data, a visual inspection, and an evaluation of the hydrology and hydraulics of the site to det...

K. B. King S. H. Kline J. H. Gray

1980-01-01

92

Radiation consequences of a hypothetical failure of a dam at the coolant reservoir of the chernobyl nuclear power plant  

Microsoft Academic Search

Mathematical simulation is used to estimate the possible radiation consequences of an accidental failure of the protective\\u000a dam of the coolant reservoir at the Chernobyl nuclear power plant. The dynamics of the emptying of the reservoir and the escape\\u000a of radionuclides is calculated. The additional contamination of bottom deposits in the Dnepr River, which can be caused by\\u000a the accidental

A. L. Kononovich; A. M. Prudovskii; S. Ya. Shkol'nikov; A. E. Asarin; A. N. Zhirkevich; B. Ya. Oskolkov; A. V. Nosovskii; L. E. Kulikov; Yu. A. Ostryanin

2000-01-01

93

Assessment of Vegetation Establishment on Tailings Dam at an Iron Ore Mining Site of Suburban Beijing, China, 7 Years After Reclamation with Contrasting Site Treatment Methods  

NASA Astrophysics Data System (ADS)

Strip-mining operations greatly disturb soil, vegetation and landscape elements, causing many ecological and environmental problems. Establishment of vegetation is a critical step in achieving the goal of ecosystem restoration in mining areas. At the Shouyun Iron Ore Mine in suburban Beijing, China, we investigated selective vegetation and soil traits on a tailings dam 7 years after site treatments with three contrasting approaches: (1) soil covering (designated as SC), (2) application of a straw mat, known as "vegetation carpet", which contains prescribed plant seed mix and water retaining agent (designated as VC), on top of sand piles, and (3) combination of soil covering and application of vegetation carpet (designated as SC+VC). We found that after 7 years of reclamation, the SC+VC site had twice the number of plant species and greater biomass than the SC and VC sites, and that the VC site had a comparable plant abundance with the SC+VC site but much less biodiversity and plant coverage. The VC site did not differ with the SC site in the vegetation traits, albeit low soil fertility. It is suggested that application of vegetation carpet can be an alternative to introduction of topsoil for treatment of tailings dam with fine-structured substrate of ore sands. However, combination of topsoil treatment and application of vegetation carpet greatly increases vegetation coverage and plant biodiversity, and is therefore a much better approach for assisting vegetation establishment on the tailings dam of strip-mining operations. While application of vegetation carpet helps to stabilize the loose surface of fine-structured mine wastes and to introduce seed bank, introduction of fertile soil is necessary for supplying nutrients to plant growth in the efforts of ecosystem restoration of mining areas.

Yan, Demin; Zhao, Fangying; Sun, Osbert Jianxin

2013-09-01

94

Investigation of the Failure Modes of Concrete Dams: Physical Modes Tests.  

National Technical Information Service (NTIS)

This report describes the design and testing of physical models of concrete arch dams. Two series of models are included. In the first series, a planar, two-dimensional model which represents a 1/50 scale model of the Koyna Dam in India is tested. The mod...

D. W. Harris

2002-01-01

95

DAM OVERTOPPING RESEARCH  

Technology Transfer Automated Retrieval System (TEKTRAN)

Aging of the watershed dams and development within the watersheds that have created changes in watershed hydrology have increased the potential for dam overtopping. Development around the dam and reservoir may increase the consequences of associated dam failure and, combined with financial constrai...

96

Electrodialytic Remediation of Copper Mine Tailings: Sulphuric and Citric Acid Addition  

Microsoft Academic Search

Decades of mining activities in Chile have generated large amounts of solid waste, which have been deposited in mine tailing impoundments. These impoundments cause concern due to dam failures or natural leaching to groundwater and rivers.This work shows the laboratory results of 11 electrodialytic remediation experiments on copper mine tailings with the addition of sulphuric and citric acid. Comparing this

Adrian Rojo; Henrik K. Hansen

2005-01-01

97

Question concerning causes of the failure and evaluation of the condition of the arch-gravity dam at the Sayano-Shushenskaya HPP  

Microsoft Academic Search

Two versions of possible causes of the failure at the Sayano-Shushenskoe HPP are examined: one concerning the possibility\\u000a of the transfer of force from the dam onto the structure of the machine room, and the other concerning limiting vibrations\\u000a of the No. 2 generating set, which were supposedly recorded prior to the failure.

A. P. Karpik; A. P. Epifanov; N. I. Stefanenko

2011-01-01

98

Results of Evaluation of Bolt Failures at the R.C. Byrd Locks and Dam.  

National Technical Information Service (NTIS)

During rehabilitation of the roller gates at the R.C. Byrd Locks and Dam, Gallipolis, OH, the U.S. Army Engineer District, Huntington found some of the bolts had failed. Analysis by the Construction Engineering Research Laboratory found the primary cause ...

R. A. Weber V. F. Hock S. Morefield

2003-01-01

99

A physically-based method for predicting peak discharge of floods caused by failure of natural and constructed earthen dams  

USGS Publications Warehouse

We analyse a simple, physically-based model of breach formation in natural and constructed earthen dams to elucidate the principal factors controlling the flood hydrograph at the breach. Formation of the breach, which is assumed trapezoidal in cross-section, is parameterized by the mean rate of downcutting, k, the value of which is constrained by observations. A dimensionless formulation of the model leads to the prediction that the breach hydrograph depends upon lake shape, the ratio r of breach width to depth, the side slope ?? of the breach, and the parameter ?? = (V.D3)(k/???gD), where V = lake volume, D = lake depth, and g is the acceleration due to gravity. Calculations show that peak discharge Qp depends weakly on lake shape r and ??, but strongly on ??, which is the product of a dimensionless lake volume and a dimensionless erosion rate. Qp(??) takes asymptotically distinct forms depending on whether < ??? 1 or < ??? 1. Theoretical predictions agree well with data from dam failures for which k could be reasonably estimated. The analysis provides a rapid and in many cases graphical way to estimate plausible values of Qp at the breach.We analyze a simple, physically-based model of breach formation in natural and constructed earthen dams to elucidate the principal factors controlling the flood hydrograph at the breach. Formation of the breach, which is assumed trapezoidal in cross-section, is parameterized by the mean rate of downcutting, k, the value of which is constrained by observations. A dimensionless formulation of the model leads to the prediction that the breach hydrograph depends upon lake shape, the ratio r of breach width to depth, the side slope ?? of the breach, and the parameter ?? = (V/D3)(k/???gD), where V = lake volume, D = lake depth, and g is the acceleration due to gravity. Calculations show that peak discharge Qp depends weakly on lake shape r and ??, but strongly on ??, which is the product of a dimensionless lake volume and a dimensionless erosion rate. Qp(??) takes asymptotically distinct forms depending on whether ?????1 or ?????1. Theoretical predictions agree well with data from dam failures for which k could be reasonably estimated. The analysis provides a rapid and in many cases graphical way to estimate plausible values of Qp at the breach.

Walder, J. S.; O'Connor, J. E.; Costa, J. E.

1997-01-01

100

Modelling The Run-out of Mine Tailings  

Microsoft Academic Search

The flow which results from the failure of a mine tailings dam has been modelled experimentally by the sub-aerial release from behind a lock gate of a highly concen- trated monodisperse suspension of silicon carbide particles in water. The experimen- tal results suggest that in the initial stages of these flows, fluid inertia is significant; however, as the current advances

A. J. Hogg; D. Pritchard

2002-01-01

101

Bioaccumulation of Heavy Metals in the Lizard Psammodromus algirus After a Tailing-Dam Collapse in Aznalcóllar (Southwest Spain)  

Microsoft Academic Search

Quantification of heavy metal concentrations in biota is a common technique that helps environmental managers measure the\\u000a level of pollutants circulating in ecosystems. Despite interest in heavy metals as indicators of localized pollution, few\\u000a studies have assessed these pollutants in reptiles. In 1998, the tailing pond of a pyrite mine near Aznalcóllar (southwestern\\u000a Spain), containing mud with high heavy metal

Rocío Márquez-Ferrando; Xavier Santos; Juan M. Pleguezuelos; Diego Ontiveros

2009-01-01

102

A physically-based method for predicting peak discharge of floods caused by failure of natural and constructed earthen dams  

USGS Publications Warehouse

We analyse a simple, physically-based model of breach formation in natural and constructed earthen dams to elucidate the principal factors controlling the flood hydrograph at the breach. Formation of the breach, which is assumed trapezoidal in cross-section, is parameterized by the mean rate of downcutting, k, the value of which is constrained by observations. A dimensionless formulation of the model leads to the prediction that the breach hydrograph depends upon lake shape, the ratio r of breach width to depth, the side slope ?? of the breach, and the parameter ?? = (V/ D3)(k/???gD), where V = lake volume, D = lake depth, and g is the acceleration due to gravity. Calculations show that peak discharge Qp depends weakly on lake shape r and ??, but strongly on ??, which is the product of a dimensionless lake volume and a dimensionless erosion rate. Qp(??) takes asymptotically distinct forms depending on whether ?? > 1. Theoretical predictions agree well with data from dam failures for which k could be reasonably estimated. The analysis provides a rapid and in many cases graphical way to estimate plausible values of Qp at the breach.

Walder, J. S.

1997-01-01

103

Analyzing the spillway failure of the Montedoglio dam in Central Italy  

NASA Astrophysics Data System (ADS)

The Montedoglio dam, built in the 1980s for irrigation and drinking water purposes, is an important reservoir on the Tiber River located in central Italy. The earth-fill dam is 64.30 m high with a drainage area of 276 km2. The water storage volume, with the water at the height of the spillway, is approximately 153 millions m3. On December 29, 2010 during final tests of the dam consisting to raising the reservoir level to the spillway crest, three concrete blocks of the spillway collapsed causing large damages in the territory downstream mainly to agriculture, infrastructures and other constructions (over 100 millions of euros of economic losses), luckily without casualties thanks also to timely action of the national/regional Civil Protection system. The discharge hydrograph following up the Montedoglio spillway collapse and its routing along the Tiber river valley are investigated here. The mathematical modelling of the reservoir depletion allows advancing well-founded hypotheses on the breach formation and in particular on the time interval in which the spillways collapsed found equal to 0.02 hours. The analysis is based on the recorded water reservoir level during the catastrophic event and on the comparison between the computed outflow discharge hydrograph and the one recorded at Gorgabuia equipped section located just downstream Montedoglio dam. The consequent dambreak flood wave is propagated downstream by using a one-dimensional model for flood wave routing and, based on the comparison between the flooded area extension estimated by the hydraulic model and the one observed through surveys and inspections carried out during the catastrophic event, the roughness calibration is addressed assessing different Manning roughness coefficient values for the main channel and the floodplains, respectively. For the analysis of the catastrophic event, data on water reservoir levels, river cross-sections geometry, discharges recorded at two gauged river sites and flooded area extension have been collected, thus getting a valuable knowledge which can be of support to improve the understanding and the management of dambreak events.

Tarpanelli, A.; Moramarco, T.; Barbetta, S.; Melone, F.; Berni, N.; Pandolfo, C.; Morbidelli, R.

2012-04-01

104

Causes of the catastrophic failure of an earth dam built on gypsiferous alluvium and dispersive clays (Altorricón, Huesca Province, NE Spain)  

Microsoft Academic Search

This paper analyses the causes of the catastrophic failure of an earth dam that took place on 21 January 2001 during the first filling test in the NE of Spain (Altorricón village, Huesca Province). The San Juan reservoir, with a capacity of 850,000 m3, was built in 1999 on gypsiferous mantled pediment deposits overlying Tertiary dispersive clay sediments. The basin

F. Gutiérrez; G. Desir; M. Gutiérrez

2003-01-01

105

Bioaccumulation of heavy metals in the lizard Psammodromus algirus after a tailing-dam collapse in Aznalcóllar (Southwest Spain).  

PubMed

Quantification of heavy metal concentrations in biota is a common technique that helps environmental managers measure the level of pollutants circulating in ecosystems. Despite interest in heavy metals as indicators of localized pollution, few studies have assessed these pollutants in reptiles. In 1998, the tailing pond of a pyrite mine near Aznalcóllar (southwestern Spain), containing mud with high heavy metal concentrations, collapsed, releasing 6 million m(3) of toxic sludge into the Guadiamar Basin. Here we analyze heavy metal concentrations in the most common reptile in the area, the large psammodromus, Psammodromus algirus, a rather small lizard. We quantified levels of several elements (Hg, Sb, Cd, Cr, Tl, Sn, Ba, Cu, Pb, Sr, Mn, Rb, As, and Zn) in lizard tail clips collected in and around the affected area during the springs of 2005 and 2006. Samples were collected from two contaminated localities, one directly affected by the spill, and another adjacent to the tailing pond, but not covered by toxic mud. We also collected samples from a nonpolluted control site in the same basin. We found higher concentrations of As, Tl, Sn, Pb, Cd, and Cu in lizards from the affected area than in lizards from the control site, indicating the continued presence of heavy metal pollutants in the terrestrial food chain 8 years after the mine accident. We did not uncover sexual or annual differences in heavy metal concentrations, although concentrations increased with lizard size. We discuss how heavy metals moved across the food chain to lizards, despite intensive restoration efforts after the accident, and suggest that reptiles to be included in biomonitoring programs of heavy metals pollution in terrestrial habitats. PMID:18587604

Márquez-Ferrando, Rocío; Santos, Xavier; Pleguezuelos, Juan M; Ontiveros, Diego

2008-06-28

106

Zipingpu Concrete Face Rockfill Dam Failures caused by the 8.0R Earthquake on the 12th May 2008 (Chengdu, China)  

NASA Astrophysics Data System (ADS)

The 8.0R earthquake that struck Sichuan on the 12th of May 2008, in the district of Chengdu of Southern China resulted in tenths of thousands casualties, the complete destruction of many towns and extended damages to public works. The earthquake was triggered by a reverse fault of NE-SW trend, more than 100 km long, that divides morphologically the affected area in two sections, the eastern one with mild low topography and the western one with intense relief representing the boundary of Tibet Mountains. This mountainous section is characterized by a rich drainage network that drains the greater region of the Tibet plateau. Along the trace of this high-stand for thousands of years numerous hydraulic works have been attempted in order to manage the water supply. Especially during the past decades, 400 small and large dams have been constructed. The main dam is the Zipingpu dam. It is a Concrete Face Rockfill Dam (CFRD) that has a height of 150m, a capacity of 1.2 billion m3 and includes a hydroelectric plant of 3.4 billion Kwh power. The Zipingpu dam is located 10km east of the earthquake epicenter and after the earthquake of 8.0R, the following failures were recorded: (i) Subsidence of the crown in the central part of the dam, of the order of 50cm in relation to the side survey control points, (ii) Deformation of the lower face of the dam, an area of approximately 1000 m2, (iii) Deviations and deformations of the construction elements throughout the face of the dam, (iv) Widening of construction joints (approximately 15 cm on the upper face), (v) Extended massive landslides throughout the reservoir, and (vi) Landslides on both left and right abutments of the dam causing further damages to secondary constructions. After the evaluation of the dam damages, the discharge of the reservoir was ordered through the emergency spillway in order to minimize the risk of a potential disaster for the nearby towns and especially Dujiangyan. Finally, the causes of the failures are investigated based on the available data.

Lekkas, E.

2009-04-01

107

75 FR 62024 - Metal and Nonmetal Dams  

Federal Register 2010, 2011, 2012, 2013

...and 57 RIN 1219-AB70 Metal and Nonmetal Dams AGENCY: Mine Safety and Health Administration...construction, operation, and maintenance of safe dams which can assure miners are protected from the hazards of dam failures. DATES: The comment period...

2010-10-07

108

NRC (Nuclear Regulatory Commission) Inventory of Dams.  

National Technical Information Service (NTIS)

The NRC Inventory of Dams has been prepared as required by the charter of the NRC Dam Safety Officer. The inventory lists 51 dams associated with nuclear power plant sites and 14 uranium mill tailings dams (licensed by NRC) in the U.S. as of February 1, 1...

G. E. Lear O. O. Thompson

1983-01-01

109

Arsenic concentrations in soils impacted by dam failure of coal-ash pond in Zemianske Kostolany, Slovakia.  

PubMed

In this study, the concentrations of arsenic were determined in the soils around old coal-ash pond. The soils in the study area were severely contaminated with arsenic after dam failure of the coal-ash pond. The mean concentrations of arsenic in soils collected from three sampling depths of 0-20, 20-40 and >40 cm were 173, 155 and 426 ?g/g, respectively, exceeding greatly the Dutch intervention threshold for this element. Arsenic concentrations were positively correlated with total iron and aluminium contents in the soils (r = 0.73, p < 0.001 and r = 0.72, p < 0.001, respectively), indicating that oxyhydroxides of iron and aluminium may control the distribution of arsenic in these soils. Ammonium nitrate extractant was used to mimic availability of arsenic for plant uptake from the soils. Between 0.05 and 6.21% of the total soil arsenic were extracted using a single extraction test and a significant positive correlation between soil leachate pH and arsenic extractability (r = 0.70, p < 0.01) was observed. This suggested that soil pH might play a role in the bioavailability of arsenic. PMID:21331534

Jurkovi?, L'ubomír; Hiller, Edgar; Veselská, Veronika; Pet'ková, Katarína

2011-02-18

110

A REVIEW OF CATASTROPHIC FLOW FAILURES OF DEPOSITS OF MINE WASTE AND MUNICIPAL REFUSE  

Microsoft Academic Search

Catastrophic flow failures occur in mine tailings dams and dumps of discards and other mine waste with alarming frequency. In recent years catastrophic flow failures have also occurred in dumps of municipal refuse and even in what were considered to be carefully controlled and well engineered landfills. Apart from the environmental devastation caused by these flows, they are also dangerous

G. E. BLIGHT; A. B. FOURIE

111

Modelling The Run-out of Mine Tailings  

NASA Astrophysics Data System (ADS)

The flow which results from the failure of a mine tailings dam has been modelled experimentally by the sub-aerial release from behind a lock gate of a highly concen- trated monodisperse suspension of silicon carbide particles in water. The experimen- tal results suggest that in the initial stages of these flows, fluid inertia is significant; however, as the current advances and becomes shallower, the propagation is increas- ingly controlled by viscous forces, and the flow rapidly arrests, leaving a thick layer of sediment with a well-defined front. The run-out distance is controlled both by the particle-dependent rheology of the suspension and by the initial inertial flow. We describe a dynamical model in which the suspension is treated as a single-phase non-Newtonian fluid with a yield stress. The problem of a tailings dam failure is con- sidered as an analogue of the classic shallow-water dam-break problem. We inves- tigate analytically and numerically how this model may be used to characterise the inertial-viscous transition and the eventual run-out distance of the current. We discuss how simple dynamical models may help to predict the run-out of tailings following dam breaches.

Hogg, A. J.; Pritchard, D.

112

Small dams need better management  

NASA Astrophysics Data System (ADS)

Many small dams around the world are poorly maintained and represent a safety hazard, according to Pisaniello et al. Better oversight of small dams is needed, the authors argue. The researchers reviewed literature, conducted case studies in four states in Australia, and developed policy benchmarks and best practices for small-dam management. Small dams, often just several meters high and typically privately owned by individual farmers, have historically caused major damage when they fail. For instance, in China in 1975, 230,000 people died when two large dams failed because of the cumulative failure of 60 smaller upstream dams. In the United States, in 1977 the 8-meter-high Kelly Barnes Lake dam failed, killing 39 people. Many other small-dam failures around the world have resulted in casualties and severe ecological and economic damage.

Balcerak, Ernie

2012-03-01

113

National Dam Safety Program. Pea Ridge Mine Dam (MO 30473), Mississippi - Kaskaskia - St. Louis Basin, Washington County, Missouri. Phase I Inspection Report.  

National Technical Information Service (NTIS)

Pea Ridge Mine Dam is an active tailings dam. Unlike most tailings dams in the area which were constructed for barite ore processing operations, this dam was constructed for an iron mining operation. Cobber reject is the primary material used to construct...

J. Y. Perez S. F. Gizienski

1980-01-01

114

Nueva alternativa para el control de compactación de tranques de relave. El Penetrómetro PANDA. The PANDA penetrometer: A new alternative for the compaction control of tailing dams  

Microsoft Academic Search

The cooper mining industry is one of the cornerstones of the Chilean economy and represents nearly the 36% of the world production. Copper sulfide production generates millions of tons of residues per year; among them one of major importance are known as tailings. Among the different deposits used for the bedding of these residues, the most widely used are tailing

R. Palma; J. Peña; G. Villavicencio

115

Electrodialytic remediation of copper mine tailings.  

PubMed

Mining activities in Chile have generated large amounts of solid waste, which have been deposited in mine tailing impoundments. These impoundments cause concern to the communities due to dam failures or natural leaching to groundwater and rivers. This work shows the laboratory results of nine electrodialytic remediation experiments on copper mine tailings. The results show that electric current could remove copper from watery tailing if the potential gradient was higher than 2 V/cm during 21 days. With addition of sulphuric acid, the process was enhanced because the pH decreased to around 4, and the copper by this reason was released in the solution. Furthermore, with acidic tailing the potential gradient was less than 2 V/cm. The maximum copper removal reached in the anode side was 53% with addition of sulphuric acid in 21 days experiment at 20 V using approximately 1.8 kg mine tailing on dry basis. In addition, experiments with acidic tailing show that the copper removal is proportional with time. PMID:15629576

Hansen, Henrik K; Rojo, Adrián; Ottosen, Lisbeth M

2005-01-31

116

Failure of a mine waste dump in Zimbabwe: Causes and consequences  

NASA Astrophysics Data System (ADS)

A combination of factors are considered important in causing the failure and subsequent development of a flowslide of a gold mine waste dump (or tailings dam) at Arcturus, near Harare, Zimbabwe. These factors comprise poor basal drainage, steep perimeter walls, saturation of the walls and basal sediments through continued spigoting of slurry during a period of heavy rainfall, and the effect of this saturation on the tailings. Properties of the tailings, eyewitness accounts, documentary evidence, and site characteristics are discussed. The failure and subsequent development of a fatal 300-m flowslide are reconstructed in a five-phase developmental model. The general applicability of the results is discussed.

Shakesby, Richard A.; Whitlow, J. Richard

1991-09-01

117

Dam Impacts  

NSDL National Science Digital Library

While the creation of a dam provides many benefits, it can have negative impacts on local ecosystems. Students learn about the major environmental impacts of dams and the engineering solutions used to address them.

Integrated Teaching And Learning Program

118

Dam Forces  

NSDL National Science Digital Library

Students learn how the force of water helps determine the size and shape of dams. They use clay to build models of four types of dams, and observe the force of the water against each type. They conclude by deciding which type of dam they, as Splash Engineering engineers, will design for Thirsty County.

Integrated Teaching And Learning Program And Laboratory

119

Geotechnical Characteristics of Copper Mine Tailings: A Case Study  

Microsoft Academic Search

Waste management issue in mining industry has become increasingly important. In this regard, construction of tailings dams\\u000a plays a major role. Most of the tailings dams require some kinds of remedial actions during their operational lifetime, among\\u000a which heightening is the most common. In the first stage of the remedial provisions for Sarcheshmeh Copper Complex tailings\\u000a dam in Iran, it

Abolfazl Shamsai; Ali Pak; S. Mohyeddin Bateni; S. Amir Hossein Ayatollahi

2007-01-01

120

Investigation Of The Use Of Mine Tailings For Unpaved Road Base  

Microsoft Academic Search

Tailings have been traditionally stored in ponds surrounded by tailings dams for many years but since many accidents, including fatal ones, took place that involved tailings dams, a new approach has become necessary for their storage. An approach devised by Robinsky in the early seventies for the storage and disposal of mine tailings suggests that it is more advantageous environmentally

Ali A. Mahmood; Catherine N. Mulligan

2010-01-01

121

Models of ‘appropriate’ practice in private dam safety assurance  

Microsoft Academic Search

Large dams are generally built and managed by Governments and private dams are built by individual owners. A number of horrific failures of both types have triggered serious concerns over the safety of dams in each country. For the larger dams, the response has been to spend vast amounts on structural upgrading works. Unfortunately, only a few countries have developed

John D Pisaniello; Jennifer M McKay

1998-01-01

122

National Program for Inspection of Non-Federal Dams. Williams Lake Dam (MA 00451), Merrimack River Basin, Marlborough, Massachusetts. Phase 1 Inspection Report.  

National Technical Information Service (NTIS)

Williams Lake Dam is an earth embankment dam with a downstream rubble masonry wall. The dam is about 183 ft. long and 6 ft. high. The dam is small in size and has a hazard potential of high. Failure of the dam would flood Interstate Route I-495 and a hous...

1980-01-01

123

106. DAM EARTH DIKE SUBMERSIBLE DAMS & DIKE ...  

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

106. DAM - EARTH DIKE - SUBMERSIBLE DAMS & DIKE CONN. AT MOVABLE DAM (ML-8-52/2-FS) March 1940 - Upper Mississippi River 9-Foot Channel, Lock & Dam No. 8, On Mississippi River near Houston County, MN, Genoa, Vernon County, WI

124

Cracking Dams  

NSDL National Science Digital Library

This is a comprehensive site that looks at many components of dams, including construction, destruction, and other issues. Access is organized into three levels by grade level. Information on cracks, case histories of the building and problems associated with some well known dams, and some real and imagined scenarios are included.

Polaha, Megann

125

Numerical modelling dam break analysis for water supply project  

NASA Astrophysics Data System (ADS)

Dam provides many benefits to the society, but it can also cause extensive damage to downstream area when it fails. Dam failure can cause extensive damage to properties and loss of human life due to short warning time available. In general, dam spillway was designed to drain the maximum discharge from the dam during the Probable Maximum Flood (PMF). The spillway is functioned to prevent the dam from failure due to overtopping, which can lead to the dam failure. Dam failure will result in large volume of water travelling at very high velocity to the downstream area of the dam. It can cause extensive property damage, destruction of important facilities, and significant loss of human life along the way. Due to the potential of high hazard it poses to the downstream area, a dam break analysis is considered very essential. This paper focuses into the dam failure analysis for Kahang Dam by prediction of breach flow hydrographs and generation of inundation map at downstream area. From the PMF scenario simulation, the maximum inflow is 525.12 m3/s and peak discharge from the dam during dam failure is 6188m3/s. The results are able to provide information for preparation of Emergency Response Plan (PMF), in which appropriate steps can be taken by relevant authorities to avoid significant loss of human lives.

Lariyah, M. S.; Vikneswaran, M.; Hidayah, B.; Muda, Z. C.; Thiruchelvam, S.; Abd Isham, A. K.; Rohani, H.

2013-06-01

126

Lake Nyos Dam  

NASA Astrophysics Data System (ADS)

Lake Nyos, or to be more precise, the upper 38 m of Lake Nyos, is held back by a natural dam (Figure 1) which, if it were to fail, would wreak havoc in the valleys to the north and cause a serious flood to surge down the Katsina Ala into Nigeria. Lockwood et al., [1987], who have been investigating the Lake Nyos gas disaster, which killed an estimated 1700 people in August 1986, presented a paper on the potential for disastrous failure of the Lake Nyos dam to the AGU Fall Meeting. Part of what they said was subsequently reported in New Scientist (December 10, 1987, p. 18). They have placed on record their view that the dam is only 400 years old and are reported to have stated that it is eroding away at the alarming rate of 1.5 m/yr. If their figures are correct, then surely the dam will fail within a decade or two at the most, and there is indeed cause for alarm and immediate action. However, teams from Cameroon, France, Italy, Japan , Switzerland, Britain, Nigeria, and Germany also visited Lake Nyos in the immediate aftermath of the gas disaster, and none of their reports have suggested that the dam is in itself an imminent threat.

Freeth, S. J.

127

EMBANKMENT-DAM BREACH PARAMETERS.  

USGS Publications Warehouse

The study used data from 43 embankment-dam failures to develop equations that predict breach formation model parameters. These data include the failure mode, embankment characteristics, reservoir conditions at the time of failure, geometry of the final breach, and the time taken to form the breach. Regression equations were developed to predict (1) the average width of a trapezoidal breach, (2) the average side-slope factor of a trapezoidal breach, and (3) the breach formation time.

Froehlich, David, C.

1987-01-01

128

Twin-tailed fail-over for fileservers maintaining full performance in the presence of a failure  

DOEpatents

A method for maintaining full performance of a file system in the presence of a failure is provided. The file system having N storage devices, where N is an integer greater than zero and N primary file servers where each file server is operatively connected to a corresponding storage device for accessing files therein. The file system further having a secondary file server operatively connected to at least one of the N storage devices. The method including: switching the connection of one of the N storage devices to the secondary file server upon a failure of one of the N primary file servers; and switching the connections of one or more of the remaining storage devices to a primary file server other than the failed file server as necessary so as to prevent a loss in performance and to provide each storage device with an operating file server.

Coteus, Paul W. (Yorktown Heights, NY); Gara, Alan G. (Mount Kisco, NY); Giampapa, Mark E. (Irvington, NY); Heidelberger, Philip (Cortlandt Manor, NY); Steinmacher-Burow, Burkhard D. (Mount Kisco, NY)

2008-02-12

129

Dam Failure Inundation Map Project.  

National Technical Information Service (NTIS)

At the end of the first year, we remain on schedule. Property owners were identified and contacted for land access purposes. A prototype software package has been completed and was demonstrated to the Division of Land and Natural Resources (DLNR), Nationa...

C. Johnson J. Iokepa J. Dahlman J. Michaud

2000-01-01

130

Natural Debris Dams and Debris-Dam Lakes  

NSDL National Science Digital Library

This site contains information that will help students to realize that in addition to the direct risk from debris flows and debris avalanches, voluminous deposition of volcanic material in valleys commonly forms unstable natural dams by blocking preexisting drainages and that if the size and structural integrity of the blockage is insufficient to hold back the reservoir that will form, catastrophic failure of the dam will result. Such a hazardous situation may persist for months, years, or decades following an eruption. An example is given of Mount St. Helens, where the debris avalanche raised the level of Spirit Lake 64 meters and dammed its natural outlet even higher and lakes formed in the tributaries of Coldwater and Castle Creeks. In addition, the site has links to publications and reports documenting historical landslide dams from around the world.

131

11. VIEW OF THE ROAD TO SEDIMENT DAM LOOKING FROM ...  

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

11. VIEW OF THE ROAD TO SEDIMENT DAM LOOKING FROM EDGE OF TAILINGS. WATER PUMP (FEATURE B-25) IS VISIBLE IN CENTER LEFT OF FRAME. - Nevada Lucky Tiger Mill & Mine, East slope of Buckskin Mountain, Paradise Valley, Humboldt County, NV

132

Cracking Dams  

NSDL National Science Digital Library

This interactive activity aids students in understanding structures (particularly dams), fracture mechanics, engineering, hydraulics and geotechnology. This site emphasizes analytical thinking, iterative design, multiple solutions and teamwork. Learning in this activity is mostly collaborative, particularly in the WebQuests, which complement the simulations and activities. There are also hands-on sections and case-based reasoning. There are many references and links provided for more information.

2007-06-15

133

SIMULATION TIGRIS RIVER FLOOD WAVE IN MOSUL CITY DUE TO A HYPOTHETICAL MOSUL DAM BREAK  

Microsoft Academic Search

Mosul dam is one of the biggest hydraulic structures in Iraq. It is located on Tigris River north Iraq and was selected as a case study to predict flood disasters caused by a hypothetical Mosul dam failure due to its foundation defect in which the dam had been survive since 1986 (initial time of dam operation). It is an earth-fill

Thair M. Al-Taiee; Anass M. M. Rasheed

134

One and Two-Dimensional Coupled Hydrodynamics Model for Dam Break Flow * * Project supported by the National Basic Research Program of China(973 Program, Grant No. 2003CB415203), the National Natural Science Foundation of China (Grant No.50579054)  

Microsoft Academic Search

1-D and 2-D mathematical models for dam break flow were established and verified with the measured data in laboratory. The 1-D and 2-D models were then coupled, and used to simulate the dam break flow from the reservoir tail to the dam site, the propagation of dam break waves in the downstream channel, and the submergence of dam break flow

Fang-li YANG; Xiao-feng ZHANG; Guang-ming TAN

2007-01-01

135

Enhancing the safety of tailings management facilities  

SciTech Connect

Unsafe tailings management facilities (TMFs) have caused serious accidents in Europe threatening human health/life and the environment. While advanced design, construction and management procedures are available, their implementation requires greater emphasis. An integrated research project funded by the European Union was carried out between 2002 and 2005 with the overall goal of improving the safety of TMFs (Sustainable Improvement in Safety of Tailings Facilities - TAILSAFE, http://www.tailsafe.com/). The objective of TAILSAFE was to develop and apply methods of parameter evaluation and measurement for the assessment and improvement of the safety state of tailings facilities, with particular attention to the stability of tailings dams and slurries, the special risks inherent when such materials include toxic or hazardous wastes, and authorization and management procedures for tailings facilities. Aspects of tailings facilities design, water management and slurry transport, non-destructive and minimally intrusive testing methods, monitoring and the application of sensors, intervention and remediation options were considered in TAILSAFE. A risk reduction framework (the TAILSAFE Parameter Framework) was established to contribute to the avoidance of catastrophic accidents and hazards from tailings facilities. Tailings from the mining and primary processing of metals, minerals and coal were included within the scope of TAILSAFE. The project focused on the avoidance of hazards by developing procedures and methods for investigating and improving the stability of tailings dams and tailings bodies.

Meggyes, T.; Niederleithinger, E.; Witt, K.J.; Csovari, M.; Kreft-Burman, K.; Engels, J.; McDonald, C.; Roehl, K.E. [BAM, Berlin (Germany). Federal Institute for Material Research & Testing

2008-07-01

136

A game analysis with policy suggestions for safety management of mine tailings facility  

Microsoft Academic Search

According to the serious trend of dam facility accidents, the complicity actions among local government, tailings facility and community residents are analyzed. Using game theory, two mixed strategy equilibrium models are constructed using economic game theory, that is, four stakeholders of safety management for dam reservoir, which includes central government, local government, tailings reservoir and community residents, are regarded as

Yiqing Zhao; Zhiguo Cao; Zhongxue Li; Yaqin Zhao

2010-01-01

137

Tail toy  

US Patent & Trademark Office Database

A toy having a tail attached to a flap which is tucked into clothing worn by a child at the rear so the tail appears to be part of the child. The flap is thin and has a large surface area for frictional engagement with the clothing. Both the flap and tail are soft and flexible, and the flap can detach from the clothing when the tail is pulled. In one embodiment, the flap can detach from the tail when pulled with a predetermined amount of force. Self expression, independence, knowledge and empathy for wildlife are promoted in the child by the toy. The flap can also house a story or picture relating to the animal represented by the tail, further interesting and enlightening the child.

Steiger; Vivian E. Y. (Manhattan Beach, CA)

1995-05-23

138

DSM saves the dam. [Deep Soil Mix  

Microsoft Academic Search

As US dams age and deteriorate, there is a growing need to upgrade them to meet new regulations and factors of safety. This article describes how, at Lockington Dam in Ohio's Miami Valley, construction of a deep-soil-mix soil-cement cutoff wall offered the best solution, both technically and economically, to prevent potential seepage-induced failure. Seventy-five years ago, the largest single constructing

1994-01-01

139

Geology and Dams. Volume V.  

National Technical Information Service (NTIS)

Contents: Kama Dam on river Kama; Kairakkum Dam on river Syr-Dar'ya; Head* Dam on river Vakhsh; Uch-Kurgan Dam on river Naryn; Lower-Bozsu Dam no. 4 on irrigational channel Lower-Bozsu; First Khrami Dam on the river Kharami; Dubossar Dam on r. Dniester; K...

A. A. Borovog

1971-01-01

140

Tails of waiting times and their bounds  

Microsoft Academic Search

Tails of distributions having the form of the geometric convolution are considered. In the case of light-tailed summands,\\u000a a simple proof of the famous Cramér asymptotic formula is given via the change of probability measure. Some related results\\u000a are obtained, namely, bounds of the tails of geometric convolutions, expressions for the distribution of the 1st failure time\\u000a and failure rate

Vladimir Kalashnikov; Gurami Tsitsiashvili

1999-01-01

141

Using historic aerial photography and paleohydrologic techniques to assess long-term ecological response to two Montana dam removals  

Microsoft Academic Search

The restorative potential of dam removal on ecosystem function depends on the reversibility of dam effects and its operations. While dam removal is an established engineering practice, the need for an understanding of the ecological response remains. We used paleoflood hydrology, hydrologic modeling, and aerial photo interpretation to investigate the long-term ecologic responses to dam failure and breach. We investigated

Denine Schmitz; Matt Blank; Selita Ammondt; Duncan T. Patten

2009-01-01

142

Correlation of serum IgG concentration in foals and refractometry index of the dam's pre- and post-parturient colostrums: an assessment for failure of passive transfer in foals.  

PubMed

The object of this study was to evaluate the usefulness of measuring the differences in the values of the serum total protein (DVSTP) concentration of foals and the refractometry index (DVRI) of the milk of dams before and after nursing of the colostrum for assessing failure of passive transfer (FPT) in foals. Serum samples from 31 foals were collected before the first nursing and other 1 to 6 times between 4 and 24 hr after birth. Paired colostrum and milk samples were collected from 14 of their dams at the same time. Serum samples were analyzed for IgG concentration using a single radial immunodiffusion (SRID) test (98 samples) and total protein concentration using a temperature-compensating refractometer (98 samples). Colostrum and milk samples were analyzed for refractometry index (RI) using a Brix refractometer (71 samples). DVSTP concentration and DVRI were significantly correlated with serum IgG concentration. The negative predictive values (NPVs) of DVSTP concentration for detecting serum IgG concentrations<400 mg/dl and<800 mg/dl were 98.2% and 91.3% when the cutoff value is set to 0.4 mg/dl and 0.8 mg/dl, respectively. Furthermore, the NPVs of DVRI for detecting serum IgG concentrations<400 mg/dl and<800 mg/dl were 97.3% and 96.3% when the cutoff value is set to 6% and 10%, respectively. The results suggest that measurement of DVRI is useful in assessing FPT as an initial "stall-side" screening test, because it is easy, inexpensive to perform and allows for rapid interpretation. PMID:22785030

Korosue, Kenji; Murase, Harutaka; Sato, Fumio; Ishimaru, Mutsuki; Kotoyori, Yasumitsu; Nambo, Yasuo

2012-06-08

143

National Program for Inspection of Non-Federal Dams. Lost Wilderness Lake Northern Dam MA 01059, Farmington River Basin, Tolland, Massachusetts. Phase I Inspection Report.  

National Technical Information Service (NTIS)

The dam is an earthen embankment 240 ft. long and 23 ft. high with a drop inlet principal spillway structure and a 10 inch outlet conduit. The dam is intermediate in size with a low hazard classification. Failure of the dam will not threaten any homes. Th...

1979-01-01

144

National Program for Inspection of Non-Federal Dams. West Lake Dam (MA 00288), Connecticut River Basin, Sandisfield, Massachusetts. Phase 1 Inspection Report.  

National Technical Information Service (NTIS)

The dam is an earthfill embankment about 920 feet in length, and 25 feet in height and has a reinforced concrete principle spillway, The dam has been rated fair. It has a classification of intermediate size and high hazard. Failure of the dam would pose a...

1979-01-01

145

The environmental impact of gold mine tailings footprints in the Johannesburg region, South Africa  

Microsoft Academic Search

Gold mining in South Africa resulted in vast volumes of tailings, which have been deposited in impoundments. Poor management\\u000a of most of the tailings dams resulted in the escape of seepage, adversely affecting soils and water quality. Some tailings\\u000a dams have been partially or completely reclaimed leaving contaminated footprints. These zones pose a serious threat to the\\u000a underlying dolomitic aquifers.

T. Rösner; A. van Schalkwyk

2000-01-01

146

49. LOCK AND DAM NO. 26 (REPLACEMENT). FIRST STAGE DAM ...  

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

49. LOCK AND DAM NO. 26 (REPLACEMENT). FIRST STAGE DAM -- DAM CONCRETE -- TYPICAL PIER ISOMETRIC. M-L 26(R) 40/1 - Upper Mississippi River 9-Foot Channel Project, Lock & Dam 26R, Alton, Madison County, IL

147

50. LOCK AND DAM NO. 26 (REPLACEMENT). FIRST STAGE DAM ...  

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

50. LOCK AND DAM NO. 26 (REPLACEMENT). FIRST STAGE DAM -- DAM CONCRETE -- GENERAL ARRANGEMENT -- SECTION AND ELEVATIONS. M-L 26(R) 40/3 - Upper Mississippi River 9-Foot Channel Project, Lock & Dam 26R, Alton, Madison County, IL

148

CRIB DAM, LOOKING ALONG DAM FROM WEST ABUTMENT, SHOWING PLANK ...  

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

CRIB DAM, LOOKING ALONG DAM FROM WEST ABUTMENT, SHOWING PLANK SHEATHING IN FOREGROUND. VIEW TO EAST - Kachess Dam, 1904 Cascade Canal Company Crib Dam, Kachess River, 1.5 miles north of Interstate 90 , Easton, Kittitas County, WA

149

Experimental research on the dam-break mechanisms of the Jiadanwan landslide dam triggered by the Wenchuan earthquake in China.  

PubMed

Dam breaks of landslide dams are always accompanied by large numbers of casualties, a large loss of property, and negative influences on the downstream ecology and environment. This study uses the Jiadanwan landslide dam, created by the Wenchuan earthquake, as a case study example. Several laboratory experiments are carried out to analyse the dam-break mechanism of the landslide dam. The different factors that impact the dam-break process include upstream flow, the boulder effect, dam size, and channel discharge. The development of the discharge channel and the failure of the landslide dam are monitored by digital video and still cameras. Experimental results show that the upstream inflow and the dam size are the main factors that impact the dam-break process. An excavated discharge channel, especially a trapezoidal discharge channel, has a positive effect on reducing peak flow. The depth of the discharge channel also has a significant impact on the dam-break process. The experimental results are significant for landslide dam management and flood disaster prevention and mitigation. PMID:23844387

Xu, Fu-gang; Yang, Xing-guo; Zhou, Jia-wen; Hao, Ming-hui

2013-06-04

150

Experimental Research on the Dam-Break Mechanisms of the Jiadanwan Landslide Dam Triggered by the Wenchuan Earthquake in China  

PubMed Central

Dam breaks of landslide dams are always accompanied by large numbers of casualties, a large loss of property, and negative influences on the downstream ecology and environment. This study uses the Jiadanwan landslide dam, created by the Wenchuan earthquake, as a case study example. Several laboratory experiments are carried out to analyse the dam-break mechanism of the landslide dam. The different factors that impact the dam-break process include upstream flow, the boulder effect, dam size, and channel discharge. The development of the discharge channel and the failure of the landslide dam are monitored by digital video and still cameras. Experimental results show that the upstream inflow and the dam size are the main factors that impact the dam-break process. An excavated discharge channel, especially a trapezoidal discharge channel, has a positive effect on reducing peak flow. The depth of the discharge channel also has a significant impact on the dam-break process. The experimental results are significant for landslide dam management and flood disaster prevention and mitigation.

Xu, Fu-gang; Yang, Xing-guo; Hao, Ming-hui

2013-01-01

151

Animal Tails  

NSDL National Science Digital Library

Call it tail envy. With only a vestigial nub to show for ourselves, perhaps it's no wonder that animal tails capture our attention. The following Web sites present some of the more interesting tails to be found in the animal kingdom. The first Web site contains a recent article from Discovery News describing new findings that at least one species of scorpion produces two distinct types of tail venom, which have completely different effects on their victims (1). The next site from Singapore Zoological Gardens introduces the cebids (our New World monkey cousins), some of which have amazing prehensile tails that are used like a fifth limb (2). The rattlesnake is another famously-tailed creature, highlighted in the following site from the Arizona-Sonora Desert Museum (3). The site covers the main aspects of rattlesnake natural history, including a section on how the rattle forms. The Great Plains Nature Center in Wichita, Kansas, offers a Web page devoted to the beaver, including tail trivia and an audio clip of a resident beaver surprised in his den at the Kansas Wildlife Exhibit (4). Anyone who has witnessed the freakishly fascinating spectacle of a gecko leaving its tail behind to distract a would-be predator will appreciate this brief bio of the Tokay gecko, presented by ReptileCenter.com, the Herpetologist's Portal (5). Stacy's Wag'N'Train -- offering dog-training classes in San Jose, California -- provides this online guide to dog body language, which would have a very limited vocabulary without the tail (6). So, how did the peacock get its tail? It's a simple question that has driven zoologists crazy for over a century. The next Web site (7) contains an in-depth article on the subject from the Independent (London), offered through National Geographic News. And finally, the bizarre gulper eel -- able to tie its tail in several knots -- gets is own Web page on Pangea, the Web server for the Department of Educational Leadership and Technology at Southeastern Louisiana University (8). This deep-sea curiosity uses its bioluminescent tail tip to lure hapless prey into its impossibly gigantic mouth.

Sohmer, Rachel.

2003-01-01

152

Germination, Growth, and Nodulation of Sesbania rostrata Grown in Pb\\/Zn Mine Tailings  

Microsoft Academic Search

Sesbania rostrata   in pure and amended Pb\\/Zn tailings. About 90% of seeds of S. rostrata germinated in pure Pb\\/Zn tailings, which contained high concentrations of Pb, Zn, Cu, and Cd. Although seedling growth suffered\\u000a from the adverse environment of Pb\\/Zn tailings, they became established on tailings stands, in the greenhouse, as well as\\u000a on the actual tailings dam, and completed

Z. Y. Yang; J. G. Yuan; G. R. Xin; H. T. Chang; M. H. Wong

1997-01-01

153

Mine tailings integrated investigations: The case of Rio tailings (Panasqueira Mine, Central Portugal)  

Microsoft Academic Search

Mining generates huge quantities of waste materials from ore extraction and milling operations, which accumulate in tailings and open impoundments. The risks associated with mine tailings have different nature, namely stability, rupture, surface and groundwater contamination, acid mine drainage (AMD) and precipitation of secondary minerals. In fact catastrophic failure of tailings impoundments has occurred, transporting slurry, dissolved metals and fine

C. Grangeia; P. Ávila; M. Matias; E. Ferreira da Silva

2011-01-01

154

RESEARCH ACTIVITIES ON THE EROSION MECHANICS OF OVERTOPPED EMBANKMENT DAMS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The asset value of dams and flood defense structures in the US, EU, and around the world amounts to billions of dollars. Many dams are located close to centers of population and industry and the consequences of failure of these structures include the risk of both loss of life and property. Erosion...

155

Safety Goals for High-Hazard Dams: Are Dams Too Safe?  

NASA Astrophysics Data System (ADS)

The 1977 National Dam Inspection Program determined that many high-hazard dams in the United States were incapable of passing a probable maximum flood (PMF). Retrofitting these dams was estimated to cost at least $10 billion. Since the PMF is revised upward periodically, retrofit is a continual issue. But surviving a PMF is a more stringent safety criterion than preventing other sources of dam failure; in addition, it is more stringent than safety criteria for other structures with respect to wind, earthquakes, or storm surges. This higher safety goal has large social costs. We propose an alternative safety goal, separating property damage from possible loss of lives. For a proposed dam whose failure could cause large loss of life or property damage, a careful evaluation should be done as to whether the dam should be built. For dams that impose smaller hazards, property damage should be handled by an analysis based on expected values of annualized benefits and costs. An adjustment for scale could be used if the property damage were extremely large. Danger to lives should be handled by establishing programs to warn and evacuate people. Our proposal should (1) lead to less injury and death, (2) use society's limited resources more efficiently, and (3) put the determination of safety goals on a more scientific and sensible basis.

Lave, Lester B.; Resendiz-Carrillo, Daniel; McMichael, Francis C.

1990-07-01

156

Hoover Dam Learning Packet.  

ERIC Educational Resources Information Center

This learning packet provides background information about Hoover Dam (Nevada) and the surrounding area. Since the dam was built at the height of the Depression in 1931, people came from all over the country to work on it. Because of Hoover Dam, the Colorado River was controlled for the first time in history and farmers in Nevada, California, and…

Bureau of Reclamation (Dept. of Interior), Washington, DC.

157

Hoover Dam Learning Packet.  

ERIC Educational Resources Information Center

|This learning packet provides background information about Hoover Dam (Nevada) and the surrounding area. Since the dam was built at the height of the Depression in 1931, people came from all over the country to work on it. Because of Hoover Dam, the Colorado River was controlled for the first time in history and farmers in Nevada, California, and…

Bureau of Reclamation (Dept. of Interior), Washington, DC.

158

DEEP SOIL MIXING FOR SEISMIC REMEDIATION OF THE CLEMSON UPPER AND LOWER DIVERSION DAMS  

Microsoft Academic Search

The Clemson Upper and Lower Diversion Dams are similar, random earthfill dams constructed in 1960-1961 to protect lands and facilities at Clemson University. Because of a loose silty sand \\/ sandy silt alluvial foundation layer, the dams were susceptible to downstream liquefaction slope failures during or following the design earthquake (amax = 0.2g). The remedial design to prevent seismic instability

Lee Wooten

2005-01-01

159

NUMERICAL ANALYSIS OF AN EARTHFILL DAM IN STAGED CONSTRUCTION ON SOFT SUBSOIL  

Microsoft Academic Search

The staged construction is considered a very effective technique of construction earthfill dams on most soft subsoils. The paper is devo ted to study the behaviour and stability of an earthfill dam in staged construction using the finite element method. Stress-strain behaviour and pore-water pressure are investigated for each stage of dam construction. Failure mecha- nism and factor of safety

Tho X. Tran

160

Elastoplastic Effective Stress Analysis of Centrifugal Shaking Tests of a Rockfill Dam  

Microsoft Academic Search

No earthquake has caused failure or severe damage to any rockfill dams with bodies of wellcompacted r ock materials. It is important to estimate the damage grade quantitatively in order to evaluate a seismic performance of a dam against a large earthquake. A centrifugal shaking model test of a rockfill dam was performed under centrifugal force field of 50g to

T. Iwashita

161

Proceedings of Dam Safety Training Program.  

National Technical Information Service (NTIS)

The papers included are titled: Assessment of Instrumentation Data, Design of Concrete Dams, Instrumentation of Dams, TVA's Dam Safety Program, Design of Earth Dams, Hydrologic Design of Dams, Emergency Action Plans, TVA Dam Safety Studies and Project Reh...

D. T. Tanner R. C. Sloan C. D. Tockstein J. T. Price S. D. Stone

1985-01-01

162

Bringing Down Our Dams: Trends in American Dam Removal Rationales  

Microsoft Academic Search

Over 76,000 dams have been constructed on American rivers to provide services such as flood protection, water storage, hydroelectric power, and navigation. Although most dams continue to provide sufficient benefits to retain the structure, dam removal is becoming increasingly common. This study involved the construction of a dam removal database to analyze spatial and temporal trends in dam removal. The

Molly M. Pohl

2002-01-01

163

16. Parker Dam, only top fourth of dam visible, at ...  

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

16. Parker Dam, only top fourth of dam visible, at 320' high, Parker Dam is one of the highest in the world. Much of this height is because dam penetrates well below river bottom to fasten to bedrock. - Parker Dam, Spanning Colorado River between AZ & CA, Parker, La Paz County, AZ

164

Stability analysis of White Oak Dam  

SciTech Connect

White Oak Dam is located in the White Oak Creek watershed which provides the primary surface drainage for Oak Ridge National Laboratory. A stability analysis was made on the dam by Syed Ahmed in January 1994 which included an evaluation of the liquefaction potential of the embankment and foundation. This report evaluates the stability of the dam and includes comments on the report prepared by Ahmed. Slope stability analyses were performed on the dam and included cases for sudden drawdown, steady seepage, partial pool and earthquake. Results of the stability analyses indicate that the dam is stable and failure of the structure would not occur for the cases considered. The report prepared by Ahmed leads to the same conclusions as stated above. Review of the report finds that it is complete, well documented and conservative in its selection of soil parameters. The evaluation of the liquefaction potential is also complete and this report is in agreement with the findings that the dam and foundation are not susceptible to liquefaction.

NONE

1995-04-11

165

Focusing attention on dam safety  

Microsoft Academic Search

When people think of hydropower, an image of a dam often comes to mind. Indeed, at most high-hazard dams, there is a hydro plant. A North American hydro industry survey shows that dams and their safety are a priority among project owners. The survey identified several recent dam safety activities: development of safety evaluation programs; dam rehabilitation for greater stability;

1992-01-01

166

Bearing capacity of desiccated tailings  

SciTech Connect

The development of matric suctions in soils contributes to their shear strength, resulting in an enhanced factor of safety against bearing-capacity failure. In this paper, matric suction profiles of desiccated mine tailings are predicted from a steady-state solution for evaporative conditions, and from an isothermal mathematical model that simulates liquid and vapor water flow through soils. The shear-strength envelope with respect to matric suction is established by testing reconstituted tailings samples in a modified triaxial cell, in which matric suction can be controlled. The contribution of matric suction to the shear strength is interpreted as an additional apparent cohesion for use in bearing-capacity calculations. Because of the nonlinearity of the shear-strength profile, a numerical method of analysis is adopted to predict the ultimate bearing capacity of the desiccated tailings. A subsequent decrease in bearing capacity following 2D water infiltration into a partially capped tailings deposit and accompanying suction loss is investigated.

Rassam, D.W.; Williams, D.J. [Univ. of Queensland, Brisbane, Queensland (Australia). Dept. of Civil Engineering

1999-07-01

167

Mine waste embankments need same engineering attention as earthfill dam  

Microsoft Academic Search

Coal tailings dams and waste piles are the garbage of coal production, but their volumes make them major structures. Without adequate engineering design, they are like bombs waiting to be exploded. Mine waste embankments may fail for several reasons: weak foundations, very steep slopes or excessive heights, high piezometric water levels, overtopping of the pond water, and piping of fine

1976-01-01

168

The 1786 earthquake-triggered landslide dam and subsequent dam-break flood on the Dadu River, southwestern China  

NASA Astrophysics Data System (ADS)

Chinese historic documents recorded that on June 1, 1786, a strong M=7.75 earthquake occurred in the Kangding-Luding area, Sichuan, southwestern China, resulting in a large landslide that fell into the Dadu River. As a result, a landslide dam blocked the river. Ten days later, the sudden breaching of the dam resulted in catastrophic downstream flooding. Historic records document over 100,000 deaths by the flood. This may be the most disastrous event ever caused by landslide dam failures in the world. Although a lot of work has been carried out to determine the location, magnitude and intensity of the 1786 earthquake, relatively little is known about the occurrence and nature of the landslide dam. In this paper, the dam was reconstructed using historic documents and geomorphic evidence. It was found that the landslide dam was about 70 m high, and it created a lake with a water volume of about 50×106 m3 and an area of about 1.7 km2. The landslide dam breached suddenly due to a major aftershock on June 10, 1786. The peak discharge at the dam breach was estimated using regression equations and a physically based predictive equation. The possibility of a future failure of the landslide seems high, particularly due to inherent seismic risk, and detailed geotechnical investigations are strongly recommended for evaluating the current stability of the landslide.

Dai, F. C.; Lee, C. F.; Deng, J. H.; Tham, L. G.

2005-02-01

169

Dammed or Damned?  

ERIC Educational Resources Information Center

Summarizes issues raised at a workshop on "People and Dams" organized by the Society for Participatory Research in Asia. Objectives were to (1) understand problems created by dams for people, (2) consider forces affecting displaced populations and rehabilitation efforts, and (3) gain a perspective on popular education efforts among affected…

Hirsch, Philip

1988-01-01

170

GeoGuide: Dams!  

NSDL National Science Digital Library

The site offers an interactive discussion of different vantage points associated with dam building. It describes some of the engineering and environmental issues that go into the process of selecting a site for building a dam and the conditions necessary for electrical generation. Links to classroom and family activities are organized by grade level.

171

NEW ENGLAND DAMS  

EPA Science Inventory

With the National Dam Inspection Act (P.L. 92-367) of 1972, Congress authorized the U.S. Army Corps of Engineers (USACE) to inventory dams located in the United States. The Water Resources Development Act of 1986 (P.L 99-662) authorized USACE to maintain and periodically publish...

172

1. GORGE HIGH DAM. THIS THIN ARCH DAM WITH A ...  

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

1. GORGE HIGH DAM. THIS THIN ARCH DAM WITH A GRAVITY SECTION IS THE THIRD DAM BUILT BY SEATTLE CITY LIGHT TO PROVIDE WATER FOR GORGE POWERHOUSE AND WAS COMPLETED IN 1961, 1989. - Skagit Power Development, Gorge High Dam, On Skagit River, 2.9 miles upstream from Newhalem, Newhalem, Whatcom County, WA

173

Simulating dam-breach flood scenarios of the Tangjiashan landslide dam induced by the Wenchuan Earthquake  

NASA Astrophysics Data System (ADS)

Floods from failures of landslide dams can pose a hazard to people and property downstream, which have to be rapidly assessed and mitigated in order to reduce the potential risk. The Tangjiashan landslide dam induced by the Mw = 7.9 2008 Wenchuan earthquake had impounded the largest lake in the earthquake affected area with an estimated volume of 3 × 108 m3, and the potential catastrophic dam breach posed a serious threat to more than 2.5 million people in downstream towns and Mianyang city, located 85 km downstream. Chinese authorities had to evacuate parts of the city until the Tangjiashan landslide dam was artificially breached by a spillway, and the lake was drained. We propose an integrated approach to simulate the dam-breach floods for a number of possible scenarios, to evaluate the severity of the threat to Mianyang city. Firstly, the physically-based BREACH model was applied to predict the flood hydrographs at the dam location, which were calibrated with observational data of the flood resulting from the artificial breaching. The output hydrographs from this model were inputted into the 1-D-2-D SOBEK hydrodynamic model to simulate the spatial variations in flood parameters. The simulated flood hydrograph, peak discharge and peak arrival time at the downstream towns fit the observations. Thus this approach is capable of providing reliable predictions for the decision makers to determine the mitigation plans. The sensitivity analysis of the BREACH model input parameters reveals that the average grain size, the unit weight and porosity of the dam materials are the most sensitive parameters. The variability of the dam material properties causes a large uncertainty in the estimation of the peak flood discharge and peak arrival time, but has little influence on the flood inundation area and flood depth downstream. The effect of cascading breaches of smaller dams downstream of the Tangjiashan dam was insignificant, due to their rather small volumes, which were only 2% of the volume of the Tangjiashan lake. The construction of the spillway was proven to have played a crucial role in reducing the dam-breach flood, because all the other natural breach scenarios would have caused the flooding of the downstream towns and parts of Mianyang city. However, in retrospect improvements on the spillway design and the evacuation planning would have been possible. The dam-break flood risk will be better controlled by reducing the spillway channel gradient and the porosity of the coating of the channel bottom. The experience and lessons we learned from the Tangjiashan case will contribute to improving the hazard mitigation and risk management planning of similar events in future.

Fan, X.; Tang, C. X.; van Westen, C. J.; Alkema, D.

2012-10-01

174

Rubber dam usage for endodontic treatment: a review.  

PubMed

Rubber dam has been available to the dental profession for over 140 years. During this time, the use of rubber dam has been perfected, universally taught and recommended by professional organizations. Unfortunately, its consistent use has been rejected by many in the profession. The literature suggests that rubber dam is not used routinely by dental practitioners for root canal treatment. Many unfounded reasons have been cited for its lack of use, including concerns over patient acceptance, time required for application, cost of equipment and materials, insufficient training, difficulty in use and low treatment fees. Failure to use rubber dam has been shown to influence the choice of root canal irrigant, has a negative impact on treatment outcome and places the patient at risk of swallowing or aspirating materials and instruments. Methods to popularize rubber dam amongst general practitioners are discussed. PMID:19825034

Ahmad, I A

2009-11-01

175

Legal Perspectives on Dam Removal  

Microsoft Academic Search

Although economic, engineering, and ecological concerns drive the debate about whether to remove or repair a dam, public acceptance of change may be the ultimate determining factor. Nonetheless, little research has looked at the socioeconomic aspects of dam removal. Drawing on Wisconsin's experience with small dam removal, this chapter synthesizes the major public concerns about dam removal and introduces the

MARGARET B. BOWMAN; Sara E. Johnson

2002-01-01

176

Gypsum-karst problems in constructing dams in the USA  

NASA Astrophysics Data System (ADS)

Gypsum is a highly soluble rock and is dissolved readily to form caves, sinkholes, disappearing streams, and other karst features that typically are also present in limestones and dolomites. Gypsum karst is widespread in the USA and has caused problems at several sites where dams were built, or where dam construction was considered. Gypsum karst is present (at least locally) in most areas where gypsum crops out, or is less than 30-60 m below the land surface. These karst features can compromise on the ability of a dam to hold water in a reservoir, and can even cause collapse of a dam. Gypsum karst in the abutments or foundation of a dam can allow water to pass through, around, or under a dam, and solution channels can enlarge quickly, once water starts flowing through such a karst system. The common procedure for controlling gypsum karst beneath the dam is a deep cut-off trench, backfilled with impermeable material, or a close-spaced grout curtain that hopefully will fill all cavities. In Oklahoma, the proposed Upper Mangum Dam was abandoned before construction, because of extensive gypsum karst in the abutments and impoundment area. Catastrophic failure of the Quail Creek Dike in southwest Utah in 1989 was due to flow of water through an undetected karstified gypsum unit beneath the earth-fill embankment. The dike was rebuilt, at a cost of US 12 million, with construction of a cut-off trench 600 m long and 25 m deep. Other dams in the USA with severe gypsum-karst leakage problems in recent years are Horsetooth and Carter Lake Dams, in Colorado, and Anchor Dam, in Wyoming.

Johnson, Kenneth S.

2008-01-01

177

The influence of water-soluble As(III) and As(V) on dehydrogenase activity in soils affected by mine tailings  

Microsoft Academic Search

Dehydrogenase activity (DHA) in soils contaminated by arsenic-bearing tailings was correlated with total arsenic and total water-soluble arsenic (As(III)+As(V)) to evaluate the impact of tailings dispersion on the oxidative capacity of soil microorganisms. Georeferenced surface soil samples (0–10 cm depth) were collected at different distances from a tailings dam. In the samples farthest from the dam, all water-soluble arsenic (avg.

Pilar Fernández; Irene Sommer; Silke Cram; Irma Rosas; Margarita Gutiérrez

2005-01-01

178

1. OVERALL VIEW OF SPILLWAY SHOWING BAFFLE WALL AND TAIL ...  

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

1. OVERALL VIEW OF SPILLWAY SHOWING BAFFLE WALL AND TAIL WATERS, WITH POWERHOUSE (MI-98-C) AND SUBSTATION (MI-98-D) AT LEFT. VIEW TO SOUTH. - Cooke Hydroelectric Plant, Spillway, Cook Dam Road at Au Sable River, Oscoda, Iosco County, MI

179

The impact of the Aznalcóllar mine tailing spill on groundwater  

Microsoft Academic Search

As a consequence of a mine tailing dam collapse on the 25th April 1998, more than 4000 ha of the Guadiamar riverflat and farmlands were flooded by 4 hm3 of sulphide slurry. A number of open wells (12 of the 47 analysed) were also flooded and the water was contaminated. Before the spill, the groundwater in the aquifers was of

Marisol Manzano; Carlos Ayora; Cristina Domenech; Paloma Navarrete; Antonio Garralon; Maria-Jesús Turrero

1999-01-01

180

United States Society on Dams  

NSDL National Science Digital Library

The United States Society on Dams (USSD) is a professional organization that promotes the advancement of dam engineering and technology, and fosters public awareness of the importance of dams. The best feature on the society's home page is its excellent introduction to dams and their benefits. First, a short definition of a dam is given, and then some reasons for their construction are outlined with specific examples. There are many pictures of dams across the country, and most have explanations for their importance. Hydroelectric power as a renewable resource is discussed in detail. This Web site is a good learning resource for both kids and adults.

2002-01-01

181

Reverse Oxidation Zoning in Mine Tailings Generating Arsenic-rich Acidic Waters (Carnoulès, France)  

Microsoft Academic Search

.   The Carnoulès Pb mine closed 40 years ago, leaving tailings (pyrite-rich silts) exposed. In 1982, the tailings were gathered\\u000a and placed behind a concrete dam, above a drainage pipe, and then covered with a clay layer. The As-rich pyrite in the tailings\\u000a has oxidized; acidic water with high As concentrations (100–350 mg\\/L As) now emerges from the base of

Kouadio Koffi; Marc Leblanc; Hervé Jourde; Corinne Casiot; Séverin Pistre; Philippe Gouze; Françoise Elbaz-Poulichet

2003-01-01

182

Trace element pollution of soils by abandoned gold mine tailings, near Potchefstroom, South Africa  

Microsoft Academic Search

.   Fine-grained material eroded by wind and water from tailings dams at the abandoned Machavie Gold Mine was deposited over\\u000a an area of more than 1 km2. The high acidity (average pH of 3.4) of the tailings caused sulphide minerals to decompose and form trace-element-rich leachate.\\u000a Comparisons of the trace element content of the tailings and underlying soils with the Dutch-B

P. Aucamp; A. van Schalkwyk

2003-01-01

183

140. PLAN AND SECTION OF NEW DAM AND OLD DAM ...  

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

140. PLAN AND SECTION OF NEW DAM AND OLD DAM From Annual Report of 1872, Water Department of Philadelphia - Fairmount Waterworks, East bank of Schuylkill River, Aquarium Drive, Philadelphia, Philadelphia County, PA

184

Management of acidic effluents from tailing dams in metalliferous mines  

Microsoft Academic Search

Mining activity is one of the many causes of pollution of water resources and creates a condition of imbalance between the\\u000a land and water regime, in both quantitative and qualitative manners. Among the various causes of qualitative pollution, acid\\u000a mine drainage (AMD) is more predominant and is produced in mines when pyrite and other sulphide minerals become exposed to\\u000a the

M. R. Saharan; K. K. Gupta; A. Jamal; A. S. Sheoran

1995-01-01

185

Effects of tailing dam profiles on relative wind erosion rates  

Microsoft Academic Search

Erosion from mine treatment and associated residue areas can pose a significant environmental problem for surrounding locations from dust and other transported materials. The shape of such residue areas can influence windfield behavior by causing significant wind speed increases. Residue areas are often unprotected so that increasing the speed of wind passing over these areas will cause extra erosion. Values

P. S. Coffey; W. D. Scott; K. J. Summers

2009-01-01

186

The 1786 earthquake-triggered landslide dam and subsequent dam-break flood on the Dadu river, southwestern China  

NASA Astrophysics Data System (ADS)

Forensic studies of past hydraulic structure failures are rare despite their critical relevance to modern hydraulic design, and the writers (Dai et al., 2005) must be congratulated for their outstanding study. Herein the discussion is focused on two aspects of the conclusion. It is believed that dam overtopping was the primary cause of the Dadu river landslide dam failure, although aftershocks may have further weakened the embankment. Using physically based equations supported by recent physical model data, the maximum outflow may be estimated to be about 6000 m3/s.

Chanson, Hubert

2005-11-01

187

32. AERIAL VIEW OF TIETON DAM, UPSTREAM FACE OF DAM ...  

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

32. AERIAL VIEW OF TIETON DAM, UPSTREAM FACE OF DAM (Trashrack-structure for outlet at lower left in reservoir, spillway at upper left. Reservoir nearly empty due to drought.) - Tieton Dam, South & East of State Highway 12, Naches, Yakima County, WA

188

ECHETA DAM RIPRAP ON RESERVOIR SIDE OF THE DAM AT ...  

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

ECHETA DAM RIP-RAP ON RESERVOIR SIDE OF THE DAM AT BREACH. VIEW TO NORTH-NORTHEAST. - Echeta Dam & Reservoir, 2.9 miles east of Echeta Road at Echeta Railroad Siding at County Road 293, Echeta, Campbell County, WY

189

Application of lead stable isotopes to the Guadiamar Aquifer study after the mine tailings spill in Aznalcóllar (SW Spain)  

Microsoft Academic Search

On 25 April 1998 the tailings dam of the Aznalcóllar mine burst, a great quantity of pyrite waste sludge and acid water was spilled reaching the vicinity of the Doñana National Park. In surface and ground water samples taken a week after dam breaking, metals, trace elements and Pb isotopic ratios ( 206Pb\\/ 207Pb and 208Pb\\/ 206Pb) were analysed. In

I. Fernández; M. Olías; J. C. Cerón; J. De la Rosa

2005-01-01

190

Experiments of dam-break wave over a triangular bottom sill  

Microsoft Academic Search

The IMPACT project addressed the assessment and reduction of risks from extreme flooding caused by natural events or the failure of dams and flood defence structures. It was funded by the European Commission (EC), started in November 2001 and lasted for 3 years. This paper presents a dam-break flow experiment in a channel with a triangular bottom sill (the bump),

S. Soares-Frazão

2007-01-01

191

Dam health diagnosis and evaluation  

NASA Astrophysics Data System (ADS)

Based on the bionics principle in the life sciences field, we regard a dam as a vital and intelligent system. A bionics model is constructed to observe, diagnose and evaluate dam health. The model is composed of a sensing system (nerve), central processing unit (cerebrum) and decision-making implement (organism). In addition, the model, index system and engineering method on dam health assessment are presented. The proposed theories and methods are applied to evaluate dynamically the health of one concrete dam.

Wu, Zhongru; Su, Huaizhi

2005-06-01

192

Dam health diagnosis and evaluation  

Microsoft Academic Search

Based on the bionics principle in the life sciences field, we regard a dam as a vital and intelligent system. A bionics model is constructed to observe, diagnose and evaluate dam health. The model is composed of a sensing system (nerve), central processing unit (cerebrum) and decision-making implement (organism). In addition, the model, index system and engineering method on dam

Zhongru Wu; Huaizhi Su

2005-01-01

193

A Catalog of Italian Dams.  

National Technical Information Service (NTIS)

This handbook has been compiled with the aim to systematize the information on Italian dams in order to use it in the construction of dams in the USSR. The handbook includes information on 325 dams of height 20 m and more, constructed up to July 1, 1967. ...

V. A. Romanova

1971-01-01

194

Monitoring pool-tail fines  

NASA Astrophysics Data System (ADS)

Fine sediment < 2 and < 6 mm deposited in pool-tail areas of mountain streams is often measured to monitor changes in the supply of fines (e.g., by dam removal, bank erosion, or watershed effects including fires and road building) or to assess the status and trend of aquatic ecosystems. Grid counts, pebble counts, and volumetric bedmaterial samples are typically used to quantify pool-tail fines. Grid-count results exhibit a high degree of variability not only among streams and among operators, but also among crews performing a nearly identical procedure (Roper et al. 2010). Variability is even larger when diverse methods are employed, each of which quantifies fines in a different way: grid counts visually count surface fines on small patches within the pool-tail area, pebble counts pick up and tally surface particles along (riffle) transects, and volumetric samples sieve out fines from small-scale bulk samples; and even when delimited to pool-tail areas, individual methods focus on different sampling locales. Two main questions were analyzed: 1) Do pool-tail fines exhibit patterns of spatial variability and are some grid count schemes more likely to provide accurate results than others. 2) How and why does the percentage of fines vary among grid counts, pebble counts, and volumetric samples. In a field study, grids were placed at 7 locales in two rows across the wetted width of 10 pool tails in a 14-m wide 3rd order coarse gravel-bed mountain stream with <4% sand and <8% < 6 mm. Several pebble count transects were placed across each pool-tail area, and three volumetric samples were collected in each of three pool tails. Pebble and grid counts both indicated a fining trend towards one or both banks, sometimes interrupted by a secondary peak of fines within the central half of the wetted width. Among the five sampling schemes tested, grid counts covering the wetted width with 7 locales produced the highest accuracy and the least variability among the pools of the reach. Pebble counts between the two waterlines indicated 2-3 times more fines than grid counts, likely because grid counts did not extend exactly up to the waterline. However, when confined to the central 50% of the wetted width, grid counts indicated 1.2 and 1.6 times more fines < 2 and < 6 mm than pebble counts, likely because the plexiglass viewer used with grid counts improved the visibility of the bed. Volumetric armor layer samples (particles > 90 mm removed) indicated 1.4 and 1.2 times more fines < 2 and < 6 mm than grid counts at the same locales, while subarmor samples had 8-9 times more fines. In conclusion, methodological differences and the specific sampling locales selected by a method affect comparability of sampling results. Grid count accuracy and precision may be improved by extending both the width coverage and the sample size within a pool tail.

Bunte, K.; Potyondy, J. P.; Abt, S. R.; Swingle, K. W.

2010-12-01

195

EARTH DAM OR SPILLWAY?  

Technology Transfer Automated Retrieval System (TEKTRAN)

Aging of the US water control and management infrastructure is increasing the likelihood that some dams will be overtopped during extreme floods. As structures approach their planned service life, sediment pools fill and continued sedimentation results in a reduction in the volume available for flo...

196

Lake Nyos Dam  

Microsoft Academic Search

Lake Nyos, or to be more precise, the upper 38 m of Lake Nyos, is held back by a natural dam (Figure 1) which, if it were to fail, would wreak havoc in the valleys to the north and cause a serious flood to surge down the Katsina Ala into Nigeria. Lockwood et al., [1987], who have been investigating the

S. J. Freeth

1988-01-01

197

CG-DAMS: Concrete gravity dam stability analysis software  

SciTech Connect

CG-DAMS is a finite element based program written specifically for the stability analysis of concrete gravity dams. The code automates the prediction and evaluation of cracking in the dam, along the dam-rock interface, and in the foundation using incremental nonlinear analysis techniques based on the smeared crack'' approach. Its primary application is in the computation of dam-rock interface sliding stability factors of safety. The automated procedure for crack propagation analysis replaces the trial-and-error cracked-base analysis method commonly used in gravity dam safety analyses. This Application manual of CG-DAMS illustrates, through sample problems, the many features of the software. Example problems illustrate the capabilities of both CG-DAMS-PC and CG-DAMS-ABAQUS. CG-DAMS-PC is a menu driven program that runs on 386/486 PCs under the DOS operating system (4 Megabytes RAM, 25 Megabytes of hard disk space). CG-DAMS-ABAQUS is a pre- and post-processor along with a concrete constitutive model and distributed load module that interfaces with the ABAQUS general purpose finite element program. The PC program contains thermal analysis capabilities, a rough crack constitutive model, and an interface to the CRFLOOD software not available with the ABAQUS version. The CG-DAMS-ABAQUS program contains time marching dynamic analysis capabilities not available with the PC program. Example analyses presented include static, pseudo dynamic, and time marching dynamic analyses. The manual also presents sensitivity evaluations on mesh size and foundation material strength. Comparisons are presented between CG-DAMS and gravity method calculations. Comparisons with other finite element software are included for the dynamic time history analyses.

Not Available

1993-01-01

198

226Ra bioavailability to plants at the Urgeiriça uranium mill tailings site.  

PubMed

Large amounts of solid wastes (tailings) resulting from the exploitation and treatment of uranium ore at the Urgeiriça mine (north of Portugal) have been accumulated in dams (tailing ponds). To reduce the dispersion of natural radionuclides into the environment, some dams were revegetated with eucalyptus (Eucalyptus globolus) and pines (Pinus pinea). Besides these plants, some shrubs (Cytisus spp.) are growing in some of the dams. The objective of this study is to determine the 226Ra bioavailability from uranium mill tailings by quantifying the total and available fraction of radium in the tailings and to estimate its transfer to plants growing on the tailing piles. Plant and tailing samples were randomly collected and the activity concentration of 226Ra in plants (aerial part and roots) and tailings was measured by gamma-spectrometry. The exchangeable fraction of radium in tailings was quantified using one single step extraction with 1 mol dm-3 ammonium acetate (pH = 7) or 1 mol dm-3 calcium chloride solutions. The results obtained for 226Ra uptake by plants show that 226Ra concentration ratios for eucalyptus and pines decrease at low 226Ra concentrations in the tailings and appear relatively constant at higher radium concentrations. For shrubs, the concentration ratios increase at higher 226Ra solid waste concentrations approaching a saturation value. Percentage values of 16.0 +/- 8.3 and 12.9 +/- 8.9, for the fraction of radium extracted from the tailings, using 1 mol dm-3 ammonium acetate or calcium chloride solutions, respectively, were obtained. The 226Ra concentration ratios determined on the basis of exchangeable radium are one order of magnitude higher than those based on total radium. It can be concluded that, at a 95% confidence level, more consistent 226Ra concentration ratios were obtained when calculated on the basis of available radium than when total radium was considered, for all the dams. PMID:11379070

Madruga, M J; Brogueira, A; Alberto, G; Cardoso, F

2001-01-01

199

Length of Magnetospheric Tail  

Microsoft Academic Search

It is shown that hydromagnetic waves, through the action of radiation pressure, can prevent the tail of the magnetosphere from closing near the earth. It is argued that the tail of the magnetosphere may be 20 to 50 AU long. The tail can close at such heliocentric distances in the charge-exchange boundary shell where the solar wind is terminated and

A. J. Dessler

1964-01-01

200

Human Tail and Myelomeningocele  

Microsoft Academic Search

The human tail is rarely reported and is usually associated with underlying spina bifida occulta. A male newborn presenting a caudal appendage (human tail) with skin-covered myelomeningocele and tethered cord is described. Surgical excision of the human tail and repair of the myelomeningocele were performed 3 days after birth. After the operation, the patient had an uneventful convalescence and received

Pei-Jung Lin; Yu-Tang Chang; Hsing-I Tseng; Jan-You Lin; Yu-Sheng Huang

2007-01-01

201

Long-term neutralisation potential of red mud bauxite with brine amendment for the neutralisation of acidic mine tailings  

Microsoft Academic Search

Acid mine drainage is an environmental problem produced when sulphide in mine tailings dams comes in contact with O2, bacteria and water. Oxidation occurs and a succession of reactions is responsible for producing acid and metals in the environment. One solution proposed is to use red mud bauxite (RMB) that is very alkaline to neutralise acidic tailings. Previous experiments showed

M. Paradis; J. Duchesne; A. Lamontagne; D. Isabel

2007-01-01

202

Risk Perception Analysis Related To Existing Dams In Italy  

NASA Astrophysics Data System (ADS)

In the first part of this work, the progress of Italian National Rules about dams design, construction and operation are presented to highlight the strong connection existing between the promulgation of new decrees, as a consequence of a dam accidents, and the necessity to prevent further loss of lives and goods downstream. Following the Gleno Dam failure (1923), a special Ministerial Committee wrote out the first Regulations and made the proposal to establish, within the High Council of Public Works, a special department that become soon the "Dam Service", with the tasks of control and supervision about construction and operation phases of the dams and their reservoirs. A different definition of tasks and the structure of Dam Service were provided in accordance with law n° 183/1989, which transferred all the technical services to the Office of the Prime Minister; the aim was to join the Dam Office with the Department for National Technical Services, with the objective of increasing the knowledge of the territory and promoting the study on flood propagation downstream in case of operations on bottom outlet or hypothetical dam-break. In fact, population living downstream is not ready to accept any amount of risk because has not a good knowledge of the efforts of experts involved in dam safety, both from the operators and from the safety Authority. So it's important to optimize all the activities usually performed in a dam safety program and improve the emergency planning as a response to people's primary needs and feeling about safety from Civil Protection Authority. In the second part of the work, a definition of risk is provided as the relationship existing between probability of occurrence and loss, setting out the range within to plan for prevention (risk mitigation), thanks to the qualitative assessment of the minimum safety level that is suited to assign funds to plan for Civil Protection (loss mitigation). The basic meaning of the reliability of a zoned earthfill dam is illustrated by defining the risk analysis during its construction and operation. A qualitative "Event Tree Analysis" makes clear with an example the probability of occurrence of the events triggered by an earthquake, and leads to a classification of the damage level. Finally, a System Dynamics (SD) approach is presented to investigate possibilities of a preventive planning in relationship to the risk, so that it's possible to establish shared procedures to achieve the correct management in any crisis phase. As a qualitative result of a SD application, figure 1 presents a flow-chart about a case study on the same dam so to illustrate the emergency planning in a step by step procedure according to the Regulations.

Solimene, Pellegrino

2013-04-01

203

Simulation on particle crushing of tailings material under high pressure  

NASA Astrophysics Data System (ADS)

With continuous increase of the high tailings dam, it has an important practical and theoretical significance to study the mechanical characteristics of the tailings material under high pressures. It is indicated that strength envelopes of the tailings material have a remarkable nonlinear characteristics through the triaxial test under high pressures. A further study stated that the particle crushing has a critical effect on the mechanical behavior of the tailings material. In order to quantitatively research its influence, the grain size distribution of the tailings material is analyzed for pre-and post-test and the particle crushing of the tailings material is measured. The particle flow code is employed to simulate and monitor the sample during testing. Firstly, a model which considers the particle crushing is built under the plane strain condition. Then, a series of biaxial numerical tests of the tailings specimen are simulated by using the model. It is found that the simulation result agrees with the triaxial test. Finally, a law between the particle crushing and strain of the tailings material under different confining pressures is obtained.

Liu, Hai-ming; Liu, Yi-ming; Yang, Chun-he; Cao, Jing

2013-06-01

204

Dam Removal Express Assessment Models (DREAM)  

Microsoft Academic Search

Many dams have been removed in the recent decades in the U.S. for reasons including economics, safety, and ecological rehabilitation. More dams are under consideration for removal; some of them are medium to large-sized dams filled with millions of cubic meters of sediment. Reaching a decision to remove a dam and deciding as how the dam should be removed, however,

Yantao Cui; Gary Parker; Christian Braudrick; William E Dietrich; Brian Cluer

2006-01-01

205

Is it worth a dam?  

PubMed Central

Once a sign of modernization and growth, dams are often seen today as symbols of environmental and social devastation. Over 800,000 dams have been built worldwide to provide drinking water, flood control, hydropower, irrigation, navigation, and water storage. Dams do indeed provide these things,but at the cost of several adverse, unexpected effects: disruption of ecosystems, decline of fish stocks, forced human and animal resettlements, and diseases such as malaria, which are borne by vectors that thrive in quiet waters.

Joyce, S

1997-01-01

206

Geomorphic and Ecological Issues in Removal of Sediment-Filled Dams in the California Coast Ranges (Invited)  

NASA Astrophysics Data System (ADS)

Water-supply reservoirs in the actively eroding California Coast Ranges are vulnerable to sediment filling, thus creating obsolete impounding dams (Minear & Kondolf 2009). Once full of sediment, there is more impetus to remove dams for public safety and fish passage, but managing accumulated sediments becomes a dominant issue in dam removal planning. We analyzed the planning process and sediment management analyses for five dams, all of which have important ecological resources but whose dam removal options are constrained by potential impacts to downstream urban populations. Ringe Dam on Malibu Ck, Matilija Dam on the Ventura River, Searsville Dam on San Francisquito Ck, and Upper York Creek Dam on York Ck cut off important habitat for anadromous steelhead trout (Oncorhynchus mykiss). San Clemente Dam on the Carmel River has a working fish ladder, but only some of the migratory steelhead use it. By virtue of having filled with sediment, all five dams are at greater risk of seismic failure. San Clemente Dam is at greater risk because its foundation is on alluvium (not bedrock), and the poor-quality concrete in Matilija Dam is deteriorating from an akali-aggregate reaction. Simply removing the dams and allowing accumulated sediments to be transported downstream is not an option because all these rivers have extremely expensive houses along downstream banks and floodplains, so that allowing the downstream channel to aggrade with dam-dervied sediments could expose agencies to liability for future flood losses. Analyses of potential sediment transport have been based mostly on application of tractive force models, and have supported management responses ranging from in-situ stabilization (San Clemente and Matilija) to removal of stored sediment (York) to annual dredging to maintain capacity and prevent sediment passing over the dam (proposed for Searsville).

Kondolf, G. M.; Oreilly, C.

2010-12-01

207

Owyhee River intracanyon lava flows: does the river give a dam?  

USGS Publications Warehouse

Rivers carved into uplifted plateaus are commonly disrupted by discrete events from the surrounding landscape, such as lava flows or large mass movements. These disruptions are independent of slope, basin area, or channel discharge, and can dominate aspects of valley morphology and channel behavior for many kilometers. We document and assess the effects of one type of disruptive event, lava dams, on river valley morphology and incision rates at a variety of time scales, using examples from the Owyhee River in southeastern Oregon. Six sets of basaltic lava flows entered and dammed the river canyon during two periods in the late Cenozoic ca. 2 Ma–780 ka and 250–70 ka. The dams are strongly asymmetric, with steep, blunt escarpments facing up valley and long, low slopes down valley. None of the dams shows evidence of catastrophic failure; all blocked the river and diverted water over or around the dam crest. The net effect of the dams was therefore to inhibit rather than promote incision. Once incision resumed, most of the intracanyon flows were incised relatively rapidly and therefore did not exert a lasting impact on the river valley profile over time scales >106 yr. The net long-term incision rate from the time of the oldest documented lava dam, the Bogus Rim lava dam (?1.7 Ma), to present was 0.18 mm/yr, but incision rates through or around individual lava dams were up to an order of magnitude greater. At least three lava dams (Bogus Rim, Saddle Butte, and West Crater) show evidence that incision initiated only after the impounded lakes filled completely with sediment and there was gravel transport across the dams. The most recent lava dam, formed by the West Crater lava flow around 70 ka, persisted for at least 25 k.y. before incision began, and the dam was largely removed within another 35 k.y. The time scale over which the lava dams inhibit incision is therefore directly affected by both the volume of lava forming the dam and the time required for sediment to fill the blocked valley. Variations in this primary process of incision through the lava dams could be influenced by additional independent factors such as regional uplift, drainage integration, or climate that affect the relative base level, discharge, and sediment yield within the watershed. By redirecting the river, tributaries, and subsequent lava flows to different parts of the canyon, lava dams create a distinct valley morphology of flat, broad basalt shelves capping steep cliffs of Tertiary sediment. This stratigraphy is conducive to landsliding and extends the effects of intracanyon lava flows on channel geomorphology beyond the lifetime of the dams.

Ely, Lisa L.; Brossy, Cooper C.; House, P. Kyle; Safran, Elizabeth B.; O'Connor, Jim E.; Champion, Duane E.; Fenton, Cassandra R.; Bondre, Ninad R.; Orem, Caitlin A.; Grant, Gordon E.; Henry, Christopher D.; Turrin, Brent D.

2013-01-01

208

76 FR 12094 - Whitman River Dam, Inc.  

Federal Register 2010, 2011, 2012, 2013

...Commission [Project No. 13237-002] Whitman River Dam, Inc. Notice of Application Tendered for Filing...February 14, 2011. d. Applicant: Whitman River Dam, Inc. e. Name of Project: Crocker Dam Hydro Project. f. Location: On the Whitman...

2011-03-04

209

78 FR 62627 - Sam Rayburn Dam Rate  

Federal Register 2010, 2011, 2012, 2013

...Southwestern Power Administration Sam Rayburn Dam Rate AGENCY: Southwestern Power Administration...increases the power rate for the Sam Rayburn Dam (Rayburn) project pursuant to the Rayburn...Hydro Power and Energy Sold to Sam Rayburn Dam Electric Cooperative, Inc....

2013-10-22

210

Lightweight Concrete Dams on Rock Foundations.  

National Technical Information Service (NTIS)

The book gives the results of generalization and critical analysis of the experience of design, research, construction, and exploitation of lightweight concrete dams on rock foundations (gravity dams with expansion joints, prestressed concrete gravity dam...

L. V. Oleshkevich

1976-01-01

211

Conflicts Associated with Dam Removal in Sweden  

Microsoft Academic Search

ABSTRACT. The increasing number,of deterioratingold dams that need renovation or have lost their function make,dam removal a viable management,option. There are at least four major reasons for dam removal: safety, law and policy, economy, and ecology. Here we discuss 17 Swedish dams that were recently considered for removal. Because dam removal usually causes controversy, dam removal initiatives may succeed, fail,

Anna G. C. Lejon; Birgitta Malm Renöfält; Christer Nilsson

212

Tails of Bacterial Motility  

NASA Astrophysics Data System (ADS)

The cytoplasm of living cells provides a complex fluid environment in which intracellular bacteria live and move. By analyzing the easily visible curved actin ``comet-tail'' of polymerization-based-motility bacteria such as Listeria monocytogenes, we can learn about sub-micron structure and dynamics of the tail and of the bacterial surface enzyme that catalyzes tail formation. By characterizing the motility, we can transform such motile systems into probes of the cytoplasmic environment.

Rutenberg, Andrew; Grant, Martin

2001-03-01

213

War damages and reconstruction of Peruca dam  

SciTech Connect

The paper describes the heavy damages caused by blasting in the Peruca rockfill dam in Croatia in January 1993. Complete collapse of the dam by overtopping was prevented through quick action of the dam owner by dumping clayey gravel on the lowest sections of the dam crest and opening the bottom outlet of the reservoir, thus efficiently lowering the water level. After the damages were sufficiently established and alternatives for restoration of the dam were evaluated, it was decided to construct a diaphragm wall through the damaged core in the central dam part as the impermeable dam element and to rebuild the central clay core at the dam abutments. Reconstruction works are described.

Nonveiller, E. [Univ. of Zagreb (Croatia). Faculty of Civil Engineering; Rupcic, J. [Univ. of Zagreb (Croatia). Faculty of Civil Engineering]|[Elektroprojekt Consulting Engineering, Zagreb (Croatia); Sever, Z. [Elektroprojekt Consulting Engineering, Zagreb (Croatia)

1999-04-01

214

A Comparative Review of Environmental Policies and Laws Involving Hazardous Private Dams: 'Appropriate' Practice Models for Safe Catchments  

Microsoft Academic Search

Generally, the world’s largest dams have been erected and managedby governments, while individual owners have been responsible for privatedams. Both kinds of dams have experienced technical failures thathave resulted in tragic losses of life as well as disastrous damage to propertyand environment, and this has generated serious concerns regardingdams’ safety worldwide. In Australia, despite the fact that attention hasbeen focused

John D. Pisaniello

2011-01-01

215

Hoover Dam and Hydroelectric Power  

NSDL National Science Digital Library

This video segment is adapted from Building Big, a PBS series hosted by David Macaulay. It explores Hoover Dam's hydroelectric capabilities by explaining how it is able to harness the potential energy stored in the reservoir and convert it to electricity. It also discusses environmental impacts of the dam and others like it.

Foundation, Wgbh E.; Domain, Teachers'

216

Steam generator nozzle dam system  

Microsoft Academic Search

Many utilities are utilizing steam generator nozzle dams inside their steam generators to permit refueling and eddy-current testing or repair of steam generator tubes to occur simultaneously. Prior to consideration of this application, steam generator nozzles did not have any means to positively hold such dams in place. However, some of the current steam generator nozzles are supplied with flange

1985-01-01

217

Why Do We Build Dams?  

NSDL National Science Digital Library

Students are introduced to the concept of a dam and its potential benefits, which include water supply, electricity generation, flood control, recreation and irrigation. This lesson begins an ongoing classroom scenario in which student engineering teams working for the Splash Engineering firm design dams for a fictitious client, Thirsty County.

Integrated Teaching And Learning Program

218

Hydromechanical Analysis of Masonry Gravity Dams and their Foundations  

NASA Astrophysics Data System (ADS)

A numerical model for the hydromechanical analysis of masonry dams based on the discrete element method is presented. The dam and the rock foundation are represented as block assemblies, and a coupled flow-stress analysis is performed in an integrated manner for the entire system. Complex block shapes may be obtained by assembling elementary blocks into macroblocks, allowing the application of the model to situations ranging from equivalent continuum to fully discontinuum analysis. A contact formulation was developed based on an accurate edge-edge approach, incorporating mechanical and hydraulic behavior. The main numerical aspects are described, with an emphasis in the flow analysis explicit algorithm. An application to an existing masonry dam is presented, analyzing its present condition, with excessive seepage, and the proposed rehabilitation intervention. An evaluation of sliding failure mechanisms was also performed, showing the expected improvement in the safety of the structure.

Bretas, Eduardo M.; Lemos, José V.; Lourenço, Paulo B.

2013-03-01

219

6. GENE WASH DAM, LOOKING NORTHWEST. SURVEY REFLECTOR IN FOREGROUND ...  

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

6. GENE WASH DAM, LOOKING NORTHWEST. SURVEY REFLECTOR IN FOREGROUND FOR MONITORING MOVEMENT OF DAM AND EARTH. - Gene Wash Reservoir & Dam, 2 miles west of Parker Dam, Parker Dam, San Bernardino County, CA

220

Three Dams in Central Arizona: A Study in Technological Diversity.  

National Technical Information Service (NTIS)

Three important dams in central Arizona will be used to illustrate relevant issues of dam technology in the United States. These three structures - Roosevelt Dam (completed in 1911), Stewart Mountain Dam (1930), and Horseshoe Dam (1946) - Were built under...

D. C. Jackson C. B. Fraser

1992-01-01

221

Inspection of earthen embankment dams using time lapse electrical resistivity tomography  

NASA Astrophysics Data System (ADS)

According to the National Inventory of Dams (NID), the number of dams across the United States is approximately 85,000. Many of these dams are more than 50 years old and need vast attention to ensure their safety. It is difficult to obtain a full assessment of the dam just by visual inspections alone. This is because many problems associated with dam failure occur internally, which makes it difficult to be observed by the dam inspectors. Examples of these flaws are piping and seepage (flow of water through or around dam walls). It is in this area where geophysical methods can aid in obtaining a more confident evaluation of a dam's integrity. Electrical resistivity is one geophysical technique that would be useful in detecting internal flaws associated with seepage and piping because it is sensitive to moisture changes. A study is being conducted to examine the feasibility of electrical resistivity tomography (ERT) to map and monitor internal compromised zones within earthen embankment dams. Two quarter-scaled earthen embankment dams were built at the United States Department of Agriculture (USDA) Agriculture Research Service (ARS) Hydraulics and Engineering Research Unit (HERU) in Stillwater, Oklahoma. These two dams were constructed with known internal compromised zones that are susceptible to seepage and piping. Electrical resistivity surveys were conducted on the completed dams using a 56 electrode dipole-dipole array. The collected data was then processed using electrical resistivity tomography (ERT) imaging software and evidence of these two compromised zones was easily visible. Also, additional surveys were conducted in order to monitor the changes in electrical signatures associated with changes in these zones due to filling of the reservoir and environmental/climate changes.

Case, Jared S.

222

Reappraising historical coincidences that radically misled slope destabilization analyses of homogeneous earth dams  

Microsoft Academic Search

Gist of the message Failure and limit equilibrium are obviously the primordial concern: but problems in the desired comparisons arise from all quarters in the case of destabilizations of upstream (US) slopes of earth dams. All Prediction vs. Performance Challenges, basic to professional practice, assume that data are reasonably unquestionable, the project clearly defined, and the end-purpose of avoiding failure

V. F. B. de Mello; E. S. Larocca; R. Quintanilha; B. Meireles

2004-01-01

223

Knowledge Long Tail  

Microsoft Academic Search

This paper proposes an approach to visualize the benefits of applying contemporary technology in explicit knowledge management processes. The “Knowledge Long Tail” is a novel way of categorizing individual and organizational knowledge, and of modeling knowledge in organizations in terms of its type and frequency of use. The concept is inspired by the market long tail phenomenon raised by Chris

I. Lin; R. H. A. Seidel; D. Howell; D. Walker

2010-01-01

224

The human tail  

Microsoft Academic Search

The human tail is a congenital anomaly with a protruding lesion from the lumbosacrococcygeal region. A newborn with a tail-like structure over the coccygeal area observed since birth is presented. Lipoma accompanied by tethered spinal cord were found. In reviewing the literature from 1960 to 1997, 59 cases were described. Higher incidences of spinal dysraphism (49.15%) and tethered spinal cord

Frank L Lu; Pen-Jung Wang; Ru-Jeng Teng; Kuo-Inn Tsou Yau

1998-01-01

225

Arsenic and heavy metals in native plants at tailings impoundments in Queretaro, Mexico  

NASA Astrophysics Data System (ADS)

Ten native plants species that grow in three tailings dams from Ag, Pb, Cu and Zn mine in Queretaro, Mexico were studied. Total concentrations in tailings were 183-14,660 mg/kg As, 45-308 mg/kg Cd, 327-1754 mg/kg Pb, 149-459 mg/kg Cu and 448-505 mg/kg Zn. In the three tailings dams, the solubility of these elements is low. Tailings in dam 1 are acid generating while tailings in dams 2 and 3 are not acid-generating potential. Plants species that accumulate arsenic and heavy metals was identified; Nicotina glauca generally presented the highest concentrations (92 mg/kg As, 106 mg/kg Cd, 189 mg/kg Pb, 95 mg/kg Cu and 1985 mg/kg Zn). Other species that accumulate these elements are Flaveria pubescens, Tecoma stans, Prosopis Sp, Casuarina Sp and Maurandia antirrhiniflora. Two species were found that accumulates a large amount of metals in the root, Cenchrus ciliaris and Opuntia lasiacantha. Concentrations in soils in which plants grow were 488-5990 mg/kg As, 5-129 mg/kg Cd, 169-3638 mg/kg Pb, 159-1254 mg/kg Cu and 1431-13,488 mg/kg Zn. The Accumulation Factor (AF) determined for plants was less than 1, with exception of N. glauca for Cd. The correlation between arsenic and heavy metals found in soils and plants was low. Knowledge of plant characteristics allows it use in planning the reforestation of tailings dams in controlled manner. This will reduce the risk of potentially toxic elements are integrated into the food chain of animal species.

Santos-Jallath, José; Castro-Rodríguez, Alejandrina; Huezo-Casillas, José; Torres-Bustillos, Luis

226

History of dams at the Department of Energy`s Savannah River Site, Aiken, South Carolina  

SciTech Connect

Since the production of nuclear material at SRS for weapons required large quantities of cooling water, a series of canals, dikes, and dams were constructed to provide conveyance systems and reservoirs. This paper presents a brief overview of the history of the construction of the dams and dikes. Attention is given to the use of asphaltic concrete for 30 years (and its maintenance and repair) to line the banks of dikes and the upstream slopes of dams to prevent erosion and possible failure. The ability of asphaltic concrete in preventing dam/dike failure was proven. Benefits and drawbacks to the use of this material are discussed based on the extensive experience at SRS.

Jones, M.P. [Westinghouse Savannah River Co., Aiken, SC (United States); Wilson, C.B. [Law Engineering Inc., Atlanta, GA (United States)

1995-12-01

227

The Three Gorges Dam: an ecological perspective  

Microsoft Academic Search

The Three Gorges Dam in China is the largest dam ever built. Its impacts on the biodiversity and ecologi- cal processes in the region are causing concern to ecologists worldwide. The dam and associated environ- mental alterations may result in a number of regional changes in terrestrial and aquatic biodiversity, as well as in ecosystem structure and functioning. The dam

Jianguo Wu; Jianhui Huang; Xingguo Han; Xianming Gao; Fangliang He; Mingxi Jiang; Zhigang Jiang; Richard B. Primack; Zehao Shen

2004-01-01

228

Cost allocation in dam removal project  

Microsoft Academic Search

In many countries, the dam is removed in consideration of several reasons such as safety. When removing a dam, the polluted sedimentation flowing out of the dam may have an impact to the environment of the river and sea. Thus, dam owners may prefer to wait its removal rather than remove now. This is because they are motivated to wait

Keishi Tanimoto

2003-01-01

229

Review of Tiber Dam--Raising of Dam and Dike.  

National Technical Information Service (NTIS)

The Division of Technical Review performs conceptual reviews of the design, construction, and initial operation of dams and major structures, including modifications to such structures. The purpose of this report is to summarize and document the technical...

1982-01-01

230

Deer Creek Dam, Dam, 1,204 feet/238 degrees from intersection of ...  

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

Deer Creek Dam, Dam, 1,204 feet/238 degrees from intersection of dam complex access road and U.S. Highway 189 to center of dam, 874 feet/352 degrees from Hydroelectric Powerplant (HAER UT-93-B) to center of dam, Charleston, Wasatch County, UT

231

Geomorphic responses to large check-dam removal on a mountain river in Taiwan  

NASA Astrophysics Data System (ADS)

Dam removal has become an important aspect of river restoration in recent years, but studies documenting the physical and ecological response to dam removal are still lacking - particularly in mountain rivers and following major floods. This presentation documents the recent removal of a large dam on a coarse-grained, steep (an order of magnitude greater than on the Marmot) mountain channel in Taiwan. The Chijiawan river, a tributary of the Tachia River draining a 1236 km2 watershed, is the only habitat in Taiwan of the endangered Formosan landlocked salmon. The habitat of this fish has been cut significantly since the 1960s following construction of check dams designed to prevent reservoir sedimentation downstream. The largest and lowermost barrier on Chijiawan creek is the 15m high, "No. 1 Check Dam" built in 1971. Forty years later, in early 2011, the sediment wedge behind the dam had reached an estimated 0.2 million m3 and the dam toe had been scoured about 4m below its foundation, posing a serious risk of dam failure. For these reasons, the Shei-Pa National Park removed the dam in late May 2011. To monitor the response of the river to dam removal, we installed video cameras, time-lapse cameras, stage recorders, and turbidity sensors, conducted surveys of grain size distributions and longitudinal profiles, and carried out repeat photography. Channel changes were greatest immediately following removal as a result of the high stream power, steep energy slope, and unconsolidated alluvial fill behind the dam. Headcut propagation caused immediate removal of the sand-grade sediment and progressive channel widening. One month after dam removal, a minor flood event excavated a big wedge of sediment from the impoundment. Most of the subsequent downstream deposition occurred within 500m of the dam, with alluviation reaching up to 0.5m in places. Two months after dam removal, erosion had propagated 300m upstream into the impounded sediment along a bed profile of gradient at 1.4% at a headcut with a local gradient of 5.1%. The change in grain size was a fining of the sediment at the two downstream sites and a slight coarsening at the upstream site from April 2010 to July 2011. This is likely due to the increase in energy upstream of the dam post-removal, which has transported the fine-grained sediments downstream. As the river adjusts over coming months and years, we anticipate that observations such as these will help generate an important resource for all those concerned with dam removal and river restoration.

Wang, H.; Stark, C. P.; Cook, K. L.; Kuo, W.

2011-12-01

232

Effects of different soil ameliorants on Karee trees (Searsia lancea) growing on mine tailings dump soil—Part I: Pot trials  

Microsoft Academic Search

Rehabilitation of mine tailings dams is often a challenge due to a lack of nutrients and a poor humus reservoir prevailing in tailings soils. This is especially true for establishing longer lived species such as trees. For these reasons the effects of different soil ameliorants (woodchips compost, vermicompost, mature sewage sludge), added to the root system of Karee (Searcia lancea)

CHRISTIAN A. LANGE; KARSTEN KOTTE; MARTIN SMIT; P. W. VAN DEVENTER; LEON VAN RENSBURG

2012-01-01

233

WATER QUALITY AND METAL TRANSPORT IN WATER-COVERED MINE TAILINGS DEPOSITS AT SULPHIDE ORE MINES - IN SITU MEASUREMENTS AND MODELLING BY DGT SAMPLERS  

Microsoft Academic Search

This poster to Mine Water 2009, presents results from studies of metals in the surface layers of a mine tailing sediment from a water covered pyrite mine tailing dam in Norway. We used the Diffusive Gradients in Thin films (DGT) probe in parallell with Diffusive Equilbrium in Thin Films (DET) probe and a modified peeper to collect metals in porewater.

ODDVAR RØYSET; BIRGER BJERKENG; EIGIL IVERSEN; KARL JAN AANES

234

A review of catastrophic drainage of moraine-dammed lakes in British Columbia  

Microsoft Academic Search

Moraine-dammed lakes are common in the high mountains of British Columbia. Most of these lakes formed when valley and cirque glaciers retreated from advanced positions achieved during the Little Ice Age. Many moraine dams in British Columbia are susceptible to failure because they are steep-sided, have relatively low width-to-height ratios, comprise loose, poorly sorted sediment, and may contain ice cores

John J. Clague; Stephen G. Evans

2000-01-01

235

Human tails and pseudotails.  

PubMed

A case of a tail in a 2-week-old infant is reported, and findings from a review of 33 previously reported cases of true tails and pseudotails are summarized. The true, or persistent, vestigial tail of humans arises from the most distal remnant of the embryonic tail. It contains adipose and connective tissue, central bundles of striated muscle, blood vessels, and nerves and is covered by skin. Bone, cartilage, notochord, and spinal cord are lacking. The true tail arises by retention of structures found normally in fetal development. It may be as long as 13 cm, can move and contract, and occurs twice as often in males as in females. A true tail is easily removed surgically, without residual effects. It is rarely familial. Pseudotails are varied lesions having in common a lumbosacral protrusion and a superficial resemblance to persistent vestigial tails. The most frequent cause of a pseudotail in a series of ten cases obtained from the literature was an anomalous prolongation of the coccygeal vertebrae. Additional lesions included two lipomas, and one each of teratoma, chondromegaly , glioma, and a thin, elongated parasitic fetus. PMID:6373560

Dao, A H; Netsky, M G

1984-05-01

236

The Tail of BPM  

NASA Astrophysics Data System (ADS)

Business process management suites (BPMS's) represent one of the fastest growing segments in the software industry as organizations automate their key business processes. As this market matures, it is interesting to compare it to Chris Anderson's 'Long Tail.' Although the 2004 "Long Tail" article in Wired magazine was primarily about the media and entertainment industries, it has since been applied (and perhaps misapplied) to other markets. Analysts describe a "Tail of BPM" market that is, perhaps, several times larger than the traditional BPMS product market. This paper will draw comparisons between the concepts in Anderson's article (and subsequent book) and the BPM solutions market.

Kruba, Steve; Meyer, Jim

237

Foundation studies for theodore roosevelt dam  

Microsoft Academic Search

Theodore Roosevelt Dam, on the Salt River northeast of Phoenix, Arizona, was originally constructed as an 85.3m-high arched masonry dam between 1903 and 1911. Modifications were completed in 1996, which included raising the dam 23.5 m for dam safety puroses and additional water supply. The dam is founded on Precambrian sandstone, siltstone, and dolomite. Occasional clay partings parallel the bedding,

G. A. Scott

1997-01-01

238

Seismic safety of earth dams: A probabilistic approach  

SciTech Connect

The evaluation of the potential for slope sliding and/or liquefaction failure of earthen dams subjected to earthquake loadings is most often based on deterministic procedures of both the excitation input and of the physical model. Such treatment provides answers in the form of either factor of safety values or a yes or no as to whether liquefaction will occur or not. Uncertainties in the physical properties of the soil in the embankment and the foundation layers underlying the dam are typically treated with parametric studies. Consideration of probabilities pertaining to the uncertainties of the earthquake and of the site characterization is expected to augment the prediction of failure potential by associating slope and liquefaction failure to generic properties of the earthquake and of the site characterization. In this study, the procedures for conditional slope failure/liquefaction probabilities are formulated based on a series of simulated deterministic analyses of a dam cross section . These synthetic earthquakes emanate from a 1-D stationary stochastic process of zero mean and an analytical form of power spectral density function. The response of the dam section is formed upon a dynamic finite element approach which provides the temporal variations of the stresses, strains and pore water pressure throughout the model. The constitutive response of the granular soil skeleton and its coupling with the fluid phase is formulated based on the Biot dynamic equations of motion with nonlinear terms compensated for into soil hysteretic damping. Lastly, a stochastic approach to liquefaction based on the transferring of the input motion statistics to the cross section is presented.

Simos, N.; Costantino, C.J.; Reich, M.

1994-08-01

239

Lake Sherburne Dam Model Study.  

National Technical Information Service (NTIS)

In 1981, a proposal was made to raise the Lake Sherburne Dam crest elevation to increase the reservoir flood detention capabilities to meet IDF (inflow design flood) criteria. The discharge capacity of the existing tower structure under increased reservoi...

B. W. Mefford

1983-01-01

240

States improve dam safety legislation and regulations  

SciTech Connect

Several state dam safety agencies have helped their state governments pass new dam safety legislation of regulations during the past year. Improvements in the laws range from establishing or raising permit fees, to boosting requirements for professional licenses, to requiring emergency action plans for all significant and high-hazard dams. ASDSO tracks dam safety legislation and laws to help keep the association's members informed on progress in dam safety. In New Jersey, lawmakers passed legislation providing $1.7 million in loans for engineering studies on high-hazard dams. Similarly in Minnesota, lawmakers approved legislation providing $1.6 million for repair or removal of dams. In Colorado, new legislation creates an emergency dam repair cash fund for state engineers to cover costs of emergency actions. In South Carolina, the General Assembly passed major amendments to the Dams and Reservoirs Safety Act. The amendments require that dam owners notify the state within 30 days after title to a dam is transferred, and stipulate that owners of high-hazard and significant hazard dams prepare emergency action plans. The state also may require normal maintenance on a dam; previously, the dam had to be declared unsafe before and order could be issued. A number of other states are working on new legislation, guidelines, or regulations, including Massachusetts, New York, Washington, and Wyoming. Forty-eight states have dam safety legislation in place; Alabama and Delaware are without such legislation.

Spragens, L. (ASDSO, Lexington, KY (United States))

1993-05-01

241

ALAMO DAM DEMONSTRATION RISK ASSESSMENT  

Microsoft Academic Search

A demonstration risk assessment was conducted on the 283-foot high rolled-earthfill Alamo Dam as part of a U.S. Army Corps of Engineers (USACE) Research and Development program. The existing dam and 19 structural risk reduction alternatives were evaluated for flood, earthquake and normal operating conditions. The paper summarizes the risk assessment process, results, findings and recommendations. It also provides an

David S. Bowles; Loren R. Anderson; Joseph B. Evelyn; Terry F. Glover; David M. Van Dorpe

1999-01-01

242

"U.S. Reclamation Service, Grand River Dam, topographical map of dam ...  

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

"U.S. Reclamation Service, Grand River Dam, topographical map of dam site and construction plant. September 15, 1914." - Grand Valley Diversion Dam, Half a mile north of intersection of I-70 & Colorado State Route 65, Cameo, Mesa County, CO

243

78 FR 53494 - Dam Safety Modifications at Cherokee, Fort Loudoun, Tellico, and Watts Bar Dams  

Federal Register 2010, 2011, 2012, 2013

...TENNESSEE VALLEY AUTHORITY Dam Safety Modifications at Cherokee, Fort Loudoun, Tellico, and Watts Bar Dams AGENCY: Tennessee Valley Authority...environmental impact statement (EIS) for the dam safety modifications at Cherokee,...

2013-08-29

244

Uranium mill tailings stabilization  

SciTech Connect

Uranium mill tailings pose a potential radiation health hazard to the public. Therefore, stabilization or disposal of these tailings in a safe and environmentally sound way is needed to minimize radon exhalation and other environmental hazards. One of the most promising concepts for stabilizing U tailings is the use of asphalt emulsion to contain radon and other hazardous materials within uranium tailings. This approach is being investigated at the Pacific Northwest Laboratory. Results of these studies indicate that a radon flux reduction of greater than 99% can be obtained using either a poured-on/sprayed-on seal (3.0 to 7.0 mm thick) or an admixture seal (2.5 to 12.7 cm thick) containing about 18 wt % residual asphalt. A field test was carried out in June 1979 at the Grand Junction tailings pile in order to demonstrate the sealing process. A reduction in radon flux ranging from 4.5 to greater than 99% (76% average) was achieved using a 15.2-cm (6-in.) admix seal with a sprayed-on top coat. A hydrostatic stabilizer was used to apply the admix. Following compaction, a spray coat seal was applied over the admix as the final step in construction of a radon seal. Overburden was applied to provide a protective soil layer over the seal. Included in part of the overburden was a herbicide to prevent root penetration.

Hartley, J.N.; Koehmstedt, P.L.; Esterl, D.J.; Freeman, H.D.

1980-02-01

245

Group prepares guidelines for documenting dam performance  

SciTech Connect

The Association of State Dam Safety Officials and the Center on the Performance of Dams at Stanford University later this summer expect to complete guidelines for reporting the performance of state, federal, and private dams: A working group of state and federal dam safety engineers and consultants is developing the guidelines to identify incidents that should be reported and to establish reporting requirements. The Federal Emergency Management Agency (FEMA) is funding preparation and publication of the guidelines. The guidelines are expected to expedite the process for reporting information on dam incidents in a timely and complete manner. Much the same as the health care industry compiles and evaluates data related to the incidence of disease and the benefits of treatment, a single standard for reporting the performance of dams in the US will help create a national information base on the occurrence and consequence of dam incidents. Currently, incidents involving dam performance are not reported on a regular basis. The guidelines will define dam incidents in terms of events of engineering interest that provide insights to the safety and structural or operational integrity of dams. Examples of incidents include the performance of a dam that experiences ground motion from a large earthquake, extreme spillway or dam overtopping, rehabilitations made to satisfy dam safety requirements, embankment sliding of an earthen dam, and improper operations that leads to damage downstream. When an incident occurs, the satisfactory or unsatisfactory performance of a dam will be reported, either by a state dam safety official, the owner of the dam, or the owner's engineer.

McCann, M.W. Jr. (Stanford Univ., CA (United States))

1993-06-01

246

17. VIEW OF MAIN AND DIVERSION DAMS FROM WATERGATE AFTER ...  

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

17. VIEW OF MAIN AND DIVERSION DAMS FROM WATER-GATE AFTER REMOVAL OF DRIFTWOOD. DIVERSION DAM IN LEFT FOREGROUND, MAIN DAM TO THE RIGHT. Photographed July 18, 1938. - Forge Creek Dam-John Cable Mill, Townsend, Blount County, TN

247

OVERALL VIEW OF CASCADE CANAL COMPANY CRIB DAM, LOOKING UPSTREAM ...  

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

OVERALL VIEW OF CASCADE CANAL COMPANY CRIB DAM, LOOKING UPSTREAM FROM DIRECTION OF KACHESS DAM. VIEW TO NORTH - Kachess Dam, 1904 Cascade Canal Company Crib Dam, Kachess River, 1.5 miles north of Interstate 90 , Easton, Kittitas County, WA

248

Beaver dams, hydrological thresholds, and controlled floods as a management tool in a desert riverine ecosystem, Bill Williams River, Arizona  

USGS Publications Warehouse

Beaver convert lotic stream habitat to lentic through dam construction, and the process is reversed when a flood or other event causes dam failure. We investigated both processes on a regulated Sonoran Desert stream, using the criterion that average current velocity is < 0.2 m s-1 in a lentic reach. We estimated temporal change in the lotic:lentic stream length ratio by relating beaver pond length (determined by the upstream lentic-lotic boundary position) to dam size, and coupling that to the dam-size frequency distribution and repeated censuses of dams along the 58-km river. The ratio fell from 19:1 when no beaver dams were present to < 3:1 after 7 years of flows favourable for beaver. We investigated the dam failure-flood intensity relationship in three independent trials (experimental floods) featuring peak discharge ranging from 37 to 65 m3 s-1. Major damage (breach ??? 3-m wide) occurred at ??? 20% of monitored dams (n = 7-86) and a similar or higher proportion was moderately damaged. We detected neither a relationship between dam size and damage level nor a flood discharge threshold for initiating major damage. Dam constituent materials appeared to control the probability of major damage at low (attenuated) flood magnitude. We conclude that environmental flows prescribed to sustain desert riparian forest will also reduce beaver-created lentic habitat in a non-linear manner determined by both beaver dam and flood attributes. Consideration of both desirable and undesirable consequences of ecological engineering by beaver is important when optimizing environmental flows to meet ecological and socioeconomic goals. ?? 2010 John Wiley & Sons, Ltd.

Andersen, D. C.; Shafroth, P. B.

2010-01-01

249

American Experience: Grand Coulee Dam  

NSDL National Science Digital Library

Among many great national achievements during the Great Depression, the Grand Coulee Dam remains one of the most impressive. This fine website from the American Experience program complements a documentary that was first aired on PBS in 2012. The construction of this dam would, in the worlds of President Franklin Roosevelt, be part of a "planned promised land" that would transform the lives of farm families. The site includes a great interactive timeline, a photo gallery, and a short preview of the entire film. Additionally, the site includes two nice bonus videos, including one that deals with the processes of closing the spillway. The blog on the site includes several interesting posts on the history of the dam. Also, visitors have the opportunity to share their own stories about their own favorite iconic structures in the United States.

2012-04-27

250

Happy Tailings to You  

NSDL National Science Digital Library

In this activity, students prepare a sample of "mine tailings", then separate out desirable materials using whatever method they choose, and quantify the results. They will discover that sometimes it's hard to separate desirable minerals from undesirable ones, especially if they look alike or the crystals are of similar sizes. Students learn that old, worked-out mines contain some desirable minerals (in small quantities) mixed in with unwanted minerals, but that doesn't stop some people from trying to squeeze out the last drop. Once considered tailings (or trash), the mix may now be profitable for mining. Desirable minerals can be separated physically and chemically.

251

Human tail: nature's aberration.  

PubMed

Human tail refers to a congenital cutaneous appendix protruding from the lumbosacral region. It is usually associated with an underlying spina bifida occulta, a form of spinal dysraphism. A contiguous fibrolipoma can sometimes be seen extending from the subcutaneous portion of the tail into the inferior spinal cord, resulting in tethered cord syndrome. Management of such lesions includes complete neurologic examination and magnetic resonance imaging. Early diagnosis and microsurgical intervention can prevent development or progression of severe neurologic defects in later life. PMID:22241711

Kumar, Dipti; Kapoor, Akshay

2012-01-12

252

7 CFR 1724.55 - Dam safety.  

Code of Federal Regulations, 2013 CFR

...DEPARTMENT OF AGRICULTURE ELECTRIC ENGINEERING, ARCHITECTURAL SERVICES AND DESIGN...the U.S. Army Corps of Engineers Engineering and Design Dam Safety Assurance Program...The U.S. Army Corps of Engineers Engineering and Design Dam Safety...

2013-01-01

253

The Dramatic Methods of Hans van Dam.  

ERIC Educational Resources Information Center

Interprets for the American reader the untranslated dramatic methods of Hans van Dam, a leading drama theorist in the Netherlands. Discusses the functions of drama as a method, closed dramatic methods, open dramatic methods, and applying van Dam's methods. (SR)

van de Water, Manon

1994-01-01

254

Should We Dam Nanticoke Creek?  

NSDL National Science Digital Library

In this decision-making exercise, students investigate what would occur if a dam were built along Nanticoke Creek, a real stream just north of West Corners near the Village of Endicott, New York. They will use topographic maps to determine how much area would be flooded by the new reservoir, to study river drainages, and to consider the impacts of dams on a region. They must also consider rivers in the context of their relation to humankind. The exercise can be extended to other, more local locations having similar topography.

Childs, Philip

255

Dam Removal Express Assessment Models (DREAM)  

Microsoft Academic Search

This paper presents sample runs of the Dam Removal Express Assessment Models (DREAM) presented in the companion paper, Cui et al. (2006): DREAM-1 for simulation of sediment transport following the removal of a dam behind which the reservoir deposit is composed primarily of noncohesive sand and silt, and DREAM-2 for simulation of sediment transport following the removal of a dam

Yantao Cui; Christian Braudrick; William E. Dietrich; Brian Cluer; Gary Parker

2006-01-01

256

TECHNICAL ISSUES IN SMALL DAM REMOVAL ENGINEERING  

Microsoft Academic Search

With thousands of communities facing decisions regarding aging small dams, dam removal is often a viable option to restore aquatic habitat and relieve what can be an economic burden and public safety hazard. Although more than 500 dams have been removed from rivers and streams throughout the United States, there is relatively little published information available to guide resource managers

Brian E. Graber; Margaret Bowman; R. Scott Carney; Martin W. Doyle; Madeline Fisher; Scudder D. Mackey; Laura Wildman

257

Stability Analysis of Troy Lock and Dam,  

National Technical Information Service (NTIS)

Troy Lock, Dam, and Powerhouse are located on the Hudson River in upstate New York (Figure 1) 156 miles from New York Harbor. Troy Lock and Dam allows entrance to the New York Barge Canal which connects to the Great Lakes. This makes Troy Lock and Dam an ...

C. Pace

1987-01-01

258

Remotely installed steam generator nozzle dam system  

Microsoft Academic Search

The Busitech Remotely Installed Nozzle Dam System is for use in Westinghouse Design Nuclear Steam Generators (S\\/G). These Nozzle Dams are used to isolate the primary channel head of the S\\/G from the primary coolant loop during the refueling process. This paper addresses the attributes of these Nozzle Dams utilized in the Westinghouse Steam Generator and does not address the

C. Evans; J. Shah; R. Kaye

1990-01-01

259

"Tails" of Linguistic Survival  

ERIC Educational Resources Information Center

|Given the relatively short history of computerized corpora of spoken language, it is not surprising that few diachronic studies have been done on the grammatical features recently highlighted by the analysis of such corpora. This article, however, does take a diachronic perspective on one such feature: the syntactic feature of "tails" (Dik 1978).…

Timmis, Ivor

2010-01-01

260

Dolphin Skeleton - Tail  

NSDL National Science Digital Library

The dolphin is built to be sleek. Its body is made of almost entirely backbone (a gliding joint) which makes it very flexible under water. The ribs protect the inner organs of the dolphin and the tail beats from side to side, thrusting the animal forward.

Ketan Patel (California State University, Fullerton;Student, Biological Sciences)

2007-07-14

261

Crocodile Skeleton - Tail  

NSDL National Science Digital Library

The crocodile is a reptile that has a long and narrow skeleton. The backbone (a gliding joint) of this animal extends into a powerful tail, allowing it to swim through water. The ribs of the crocodile are small and serve to protect its inner organs.

Ketan Patel (California State University, Fullerton;Student, Biological Science)

2007-07-14

262

Internal Lifschitz tails  

NASA Astrophysics Data System (ADS)

We consider an Anderson model in v dimensions with a potential distribution supported in ( a, b)?( c, d), where c- b>4v. We prove the existence of Lifschitz tails at the edges of the internal gap at b+2v and c- 2v. This reproves results of Mezincescu.

Simon, Barry

1987-03-01

263

Teton Dam flood of June 1976, Deer Parks quadrangle, Idaho  

USGS Publications Warehouse

The failure of the Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification of these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Deer Parks quadrangle. (Woodard-USGS)

Ray, H. A.; Bennett, C. Michael; Records, Andrew W.

1976-01-01

264

Teton Dam flood of June 1976, Rigby quadrangle, Idaho  

USGS Publications Warehouse

The failure of the Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification of these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Rigby quadrangle. (Woodard-USGS)

Ray, H. A.; Bigelow, B. B.

1976-01-01

265

Teton Dam flood of June 1976, Lewisville quadrangle, Idaho  

USGS Publications Warehouse

The failure of the Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification of these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Lewisville quadrangle. (Woodard-USGS)

Ray, H. A.; Bigelow, B. B.

1976-01-01

266

Teton Dam flood of June 1976, Woodville quadrangle, Idaho  

USGS Publications Warehouse

The failure of the Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification of these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Woodville quadrangle. (Woodard-USGS)

Matthai, Howard F.; Ray, H. A.

1976-01-01

267

Teton Dam flood of June 1976, Rexburg quadrangle, Idaho  

USGS Publications Warehouse

The failure of the Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification on these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Rexburg quadrangle. (Woodard-USGS)

Harenberg, W. A.; Bigelow, B. B.

1976-01-01

268

REAR PROFILE OF TAIL FROM SECOND LEVEL OF TAIL DOCK ...  

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

REAR PROFILE OF TAIL FROM SECOND LEVEL OF TAIL DOCK STAND, SHOWING AIRCRAFT NUMBER (319), HORIZONTAL STABILIZER, TAIL CONE AND COOLING CTS FOR THE AUXILIARY POWER UNIT (APU), MECHANIC PAUL RIDEOUT IS LOWERING THE BALANCE PANELS ON THE STABILIZERS FOR LUBRICATION AND INSPECTION. - Greater Buffalo International Airport, Maintenance Hangar, Buffalo, Erie County, NY

269

ALLOWABLE OVERTOPPING OF EARTHEN DAMS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Aging of the nation’s flood control infrastructure has resulted in a need for reevaluation, and, in some instances rehabilitation, of existing earthen dams. Inadequate spillway capacity is often one of the deficiencies identified for these structures. Inadequate spillway capacity may be the result...

270

Critical Parameters for Tailings Embankments.  

National Technical Information Service (NTIS)

Geotechnical data on copper, uranium, and phosphate tailings from 41 mines were collected and analyzed to empirically establish the variability in strength properties for tailings embankments. These data were analyzed both from geotechnical and statistica...

G. B. Baecher J. S. Lin J. A. Consla W. A. Marr

1983-01-01

271

The Dam1 ring binds microtubules strongly enough to be a processive as well as energy-efficient coupler for chromosome motion  

PubMed Central

Accurate chromosome segregation during mitotic division of budding yeast depends on the multiprotein kinetochore complex, Dam1 (also known as DASH). Purified Dam1 heterodecamers encircle microtubules (MTs) to form rings that can function as “couplers,” molecular devices that transduce energy from MT disassembly into the motion of a cargo. Here we show that MT depolymerization develops a force against a Dam1 ring that is sixfold larger than the force exerted on a coupler that binds only one side of an MT. Wild-type rings slow depolymerization fourfold, but rings that include a mutant Dam1p with truncated C terminus slow depolymerization less, consistent with the idea that this tail is part of a strong bond between rings and MTs. A molecular-mechanical model for Dam1-MT interaction predicts that binding between this flexible tail and the MT wall should cause a Dam1 ring to wobble, and Fourier analysis of moving, ring-attached beads corroborates this prediction. Comparison of the forces generated against wild-type and mutant complexes confirms the importance of tight Dam1-MT association for processive cargo movement under load.

Grishchuk, Ekaterina L.; Efremov, Artem K.; Volkov, Vladimir A.; Spiridonov, Ilia S.; Gudimchuk, Nikita; Westermann, Stefan; Drubin, David; Barnes, Georjana; McIntosh, J. Richard; Ataullakhanov, Fazly I.

2008-01-01

272

Water and Dams in Today's World  

NSDL National Science Digital Library

Students learn about the importance of dams by watching a video that presents historical and current information on dams, as well as descriptions of global water resources and the hydrologic cycle. Students also learn about different types of dams, all designed to resist the forces on dams. (If the free, 15-minute "Water and Dams in Today's World" video cannot be obtained in time, the lesson can still be taught. See the Additional Multimedia Support section for how to obtain the DVD or VHS videotape, or a PowerPoint presentation with similar content [also attached].)

Integrated Teaching And Learning Program

273

The Dos Bocas dam in Puerto Rico.  

NSDL National Science Digital Library

The Dos Bocas dam in Puerto Rico was constructed in 1942 to generate hydroelectric power. Dams in this region prevent the migration of shrimp and fish to areas upstream of the dam. As a result, compared to similar reaches of undammed streams, areas that are upstream of dammed rivers have higher amounts of organic and inorganic nutrients as well as altered invertebrate populations. Loss of migratory shrimp and fish upstream from dams alters basal resources and assemblages of invertebrate competitors and prey. This photograph originally appeared on the cover of Ecological Applications (16:1) in February of 2006.

Klemow, Kenneth

2010-02-11

274

Heavy tails and currency crises  

Microsoft Academic Search

In affine models of foreign exchange rate returns, the nature of cross sectional interdependence in crisis periods hinges on the tail properties of the fundamentals' distribution. If the fundamentals exhibit thin tails like the normal distribution, the dependence vanishes asymptotically; while the dependence remains in the case of heavy tailed fundamentals as in case of the Student-t distribution. The linearity

P. Hartmann; S. Straetmans; C. G. de Vries

2010-01-01

275

Curly tail: a 50-year history of the mouse spina bifida model  

Microsoft Academic Search

This paper reviews 50 years of progress towards understanding the aetiology and pathogenesis of neural tube defects (NTD) in the curly tail (ct) mutant mouse. More than 45 papers have been published on various aspects of curly tail with the result that it is now the best understood mouse model of NTD pathogenesis. The failure of closure of the spinal

H. W. M. van Straaten; Andrew J. Copp

2001-01-01

276

Diatom communities as indicators of environmental stress in the Guadiamar River, SW. Spain, following a major mine tailings spill  

Microsoft Academic Search

An accident in a mine tailings dam caused the outflowof mud and water rich in heavy metals in April 1998that flooded the Guadiamar River and its floodplain,in the vicinity of Doñana National Park. Theimpact on the periphytic communities was evaluated byanalyzing the evolution of the diatom communitiesafter seven (November 1998) and fourteen months (June1999) of the accident. The comparison between

Sergi Sabater

2000-01-01

277

Resistivity monitoring for leakage and internal erosion detection at Hällby embankment dam  

Microsoft Academic Search

Internal erosion is one of the major reasons for embankment dam failures. Despite this, the knowledge of the temporal development of internal erosion in full scale structures is limited. Detection of internal erosion is complicated using conventional methods, and new or improved methods are appreciated. Hällby was the first Swedish embankment to get a permanently installed monitoring system intended for

P. Sjödahl; Torleif Dahlin; Sam Johansson; M. H. Loke

2008-01-01

278

Formation and failure of the Tsatichhu landslide dam, Bhutan  

Microsoft Academic Search

At 00:30 (local time) on the 10th September 2003 a joint and foliation defined wedge of material with an estimated volume\\u000a of 7–12×106 m3 slid into the narrow Tsatichhu River Valley, in Jarrey Geog, Lhuentse, eastern Bhutan. The Tsatichhu River, a north–easterly\\u000a flowing tributary of the Kurichuu River, was completely blocked by the landslide. During its movement, the landslide transitioned\\u000a into

S. A. Dunning; N. J. Rosser; D. N. Petley; C. R. Massey

2006-01-01

279

The Influence of Ground Water on Stream Restoration Following Dam Removal  

NASA Astrophysics Data System (ADS)

With the exception of ground-water seepage beneath dams and the resulting impact on structural failure, there is a void of work directly examining the downstream impacts of dams from the perspective of ground-water/surface-water interaction. This work considers alterations in an alluvial basin caused by: (1) erection of a dam upstream, (2) followed by ground-water pumping in the basin, and (3) dam removal. Theoretical results predict that when dams are removed in developed ground-water basins, downstream baseflows may be greatly reduced relative to natural baseflows, as a result of lower water table elevations in the developed basin relative to the natural setting. Without the dam as a `safety valve' providing extra streamflow during low-flow seasons, there is a real potential for ephemeral conditions downstream of the previous location of the dam as the dry season progresses. MODFLOW simulations are used to test these theoretical results, by quantifying the impact of dam removal on downstream surface water and ground water. The simulations incorporate an improved stream-aquifer interaction and streamflow routing package to represent movement of water in the vadose zone between the stream and a lowered water table. An idealized MODFLOW model with the new stream package has been constructed, which extends from the upland bedrock headwaters of a stream to the downstream sediment-filled basin. The model domain is 180 km long, 15 km wide, and 2.2 km deep, including a stream with a potential length of 180 km. In the upper reaches, the stream is divided into a north, south, and main stem with their confluence upstream of a dam situated in the domain above the bedrock/basin contact. Horizontal discretization is 1000 m in the direction parallel to the stream, 200 to 600 m perpendicular to the stream, and vertical discretization is 100 m. This modeling framework affords the opportunity to examine a variety of cases with and without the presence of an upstream dam. Initial MODFLOW results are consistent with the theoretical results regarding the impact of dam removal in developed basins, indicating that dam removal is unlikely to regenerate natural streamflows in developed ground-water basins.

Constantz, J.; Essaid, H.

2003-12-01

280

Using hydraulic modeling to address social impacts of small dam removals in southern New Jersey.  

PubMed

Small relic mill dams are common in the watersheds of southern New Jersey, dotting the landscape with many small neighborhood lakes. Originally built in the late 1800s, most of these dams have become increasingly unable to handle current design storms due to increased urbanization of the watersheds. Several of these dams have also been classified as "high hazard" by the New Jersey Department of Environmental Protection Dam Safety Division because their failure has the potential for loss of life or extensive property damage. The current private owners are generally unable to afford the high repair costs needed to rehabilitate the dams to current safety standards, and are therefore more inclined to remove them. This research analyses both the physical and social impacts of the removal of two small dams in southern New Jersey, and integrates the two seemingly disparate concepts. Using hydraulic modeling and previous case studies, it is predicted that there will be limited effects to the hydrological and biological characteristics of the stream corridor. A survey distributed to the affected homeowners that live on these lakes shows that the community, however, expects significant impacts to the bio-physical characteristics of the stream corridor, as well financial impacts to their property value and social impacts to their recreational activities. The current study exposes the widening gap between policy makers and landowners, and highlights where complete stakeholder interaction could and should occur. PMID:19008035

Wyrick, Joshua R; Rischman, Brian A; Burke, Christopher A; McGee, Craig; Williams, Chasity

2008-11-12

281

A tool to aid emergency managers and communities in appraising private dam safety and policy.  

PubMed

Issues concerning dam safety and equitable sharing of catchment run-off are receiving more attention throughout the world. This paper assesses these matters in the context of Australia, and the need for policy responses. Landholders often overlook the common law obligation to review/design dams to current standards because of high costs, leaving them vulnerable to litigation if their dam fails. The paper reports on an innovative spillway design/review procedure, applicable to southeast Australia, but transferable to any region worldwide. Dam safety policy models and guidelines derived from international best practice are linked to the procedure and intended to aid government decision-making. The procedure minimises costs to landholders and provides an acceptable level of safety assurance to downstream communities. Also discussed are recent surveys testing community attitudes to the procedure and implemented dam safety and water allocation policies. These further guide any government wanting to implement this'integrated engineering and community partnerships'approach to preventing potential disasters due to private dam failure and achieving sustainable and safe water storage and use. PMID:17461922

Pisaniello, John D; McKay, Jennifer

2007-06-01

282

Impact of a base metal slimes dam on water systems, Madziwa Mine, Zimbabwe  

NASA Astrophysics Data System (ADS)

The Mazowe Valley contains several of Zimbabwe’s largest current mining operations, is densely populated and is also a major agricultural area. The urban areas of Bindura, Goromonzi, Shamva, Marondera, Murehwa and Mutoko all draw water from within the Mazowe Valley. Irrigation of commercial crops is also a major water user. Accordingly, managing the impact of mining operations on water quality in the Mazowe Valley must be a major priority for sustainable development in this area. Madziwa Mine, 150 km north-east of Harare, is a case in point. Mining took place between 1966 and 2001. The main sulphides were chalcopyrite, pyrrhotite, pentlandite and pyrite. Waste from the mine’s plant has been disposed of via a tailings dam, the focus of this study. Surface water samples were collected at 12 sites around the slimes dam and groundwater samples were collected from six boreholes. The samples were analysed for dissolved metals using atomic absorption spectrometry and for anions using gravimetry and titration. The surface water chemical analyses showed that acidic effluent with high concentrations of iron, nickel and sulphate emanates from the tailings dam. Concentrations of metals are lower after the water has passed through natural wetlands. Chemical analysis of groundwater showed similarly high levels of acidity, sulphate and metal. These findings show that acid mine drainage is seeping from the tailings dam. Efforts are being made to reduce the effects of the acid mine drainage. For surface seepage from the dumps these efforts include diverting acidic effluent from the dump into natural wetlands that neutralise the acidity. To reduce drainage into the groundwater efforts are being made to plant trees with high evaporation rates to minimise the amount of water that can cause acid mine drainage.

Lupankwa, K.; Love, D.; Mapani, B. S.; Mseka, S.

283

18. DETAIL AT JUNCTION OF MAIN DAM AT LEFT AND ...  

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

18. DETAIL AT JUNCTION OF MAIN DAM AT LEFT AND DIVERSION DAM AT RIGHT SHOWING LOG CRIBBING. SPACES INSIDE CRIBBING WERE FILLED WITH STONE TO ANCHOR DAM; DETERIORATION OF DAM HAS ALLOWED STONE BALLAST TO WASH AWAY. Photographed July 18, 1938. - Forge Creek Dam-John Cable Mill, Townsend, Blount County, TN

284

View of upstream face of the forebay dam of Grand ...  

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

View of upstream face of the forebay dam of Grand Coulee Dam, looking west. Construction of the forebay dam, which replaced the eastern end of the original Grand Coulee Dam, was completed in 1974. - Columbia Basin Project, Grand Coulee Dam & Franklin D. Roosevelt Lake, Across Columbia River, Southeast of Town of Grand Coulee, Grand Coulee, Grant County, WA

285

Remotely installed steam generator nozzle dam system  

SciTech Connect

The Busitech Remotely Installed Nozzle Dam System is for use in Westinghouse Design Nuclear Steam Generators (S/G). These Nozzle Dams are used to isolate the primary channel head of the S/G from the primary coolant loop during the refueling process. This paper addresses the attributes of these Nozzle Dams utilized in the Westinghouse Steam Generator and does not address the Nozzle Dams utilized in the Combustion Engineering or Babcock and Wilcox Steam Generators. This Nozzle Dam System has a remote installation option which will allow installation of the Nozzle Dam with zero entry into the S/G primary channel head. The advantages of this total system is a significant reduction in radiation exposure, manpower and time of installation.

Evans, C.; Shah, J. (BUSITECH, INC., Sandy Hook, CT (US)); Kaye, R. (Duke Power Co., Catawba Nuclear Station, Newport, SC (US))

1990-01-01

286

The geomagnetic tail  

SciTech Connect

A review is presented of the plasma sheet and lobe regions of the magnetotail, focusing principally on large-scale processes or microprocesses with some large-scale effects. Consideration is given to quiet and average structures, not necessarily related to activity phases, with quasi-steady convection aspects, and with the characteristics of dynamic phases including acceleration mechanisms and single particle aspects. Attention is given to various activity models, average and quiet time properties, properties and effects of magnetospheric convection, dynamics of the magnetotail, and the near tail, substorm current wedge.

Birn, J. (USAF, Geophysics Laboratory, Hanscom AFB, MA (United States))

1991-01-01

287

Application of tailings flow analyses to field conditions  

SciTech Connect

Catastrophic failures of tailings impoundments, in which liquefied tailings flow over substantial distances, pose severe hazards to the health and safety of people in downstream areas, and have a potential for economic and environmental devastation. The purpose of this study, an extension of prior investigations, was to develop procedures to measure Bingham flow parameters for mine tailings. In addition, the analytical procedures developed by Lucia (1981) and Jeyapalan (1980) for predicting the consequences of tailings flow failures were evaluated and applied to the Tenmile Tailings Pond at Climax, Colorado. Revisions in the simplified equilibrium procedure, developed by Lucia (1981), make it more compatible with infinite slope solutions. Jeyapalan's model was evaluated using a simple rheological analogy, and it appears there are some numerical difficulties with the operation of the computer program TFLOW used to model the displacements and velocities of flow slides. Comparable flow distances can be determined using either model if the flow volume used in the simplified equilibrium procedure is estimated properly. When both analytical procedures were applied to the Tenmile Pond, it was concluded there was no potential for a flow slide at the site.

Bryant, S.M.

1983-01-01

288

Hoover Dam: The American Experience Online  

NSDL National Science Digital Library

The American Experience Online presents this companion site to its recent American Experience film about the one of the greatest hydroengineering feats in history. The Hoover Dam, in Black Canyon on the Colorado River, at the Arizona-Nevada border, was built between 1930 and 1936 and is the highest concrete arch dam in the US. The site provides a program description, an enhanced transcript of the film, a brief bibliography, a list of the dam facts, an essay that explores the economic and environmental effects of the dam, a timeline, a map, a People and Events Database, and a teacher's guide.

1999-01-01

289

World Wide Web Pages for Dam Design  

NSDL National Science Digital Library

This site is a very informative and well presented resource for dam design, primarily intended to give undergraduates or anyone interested in the subject a solid introduction to the basic concepts. Maintained at the University of Durham in Britain, there are many sections that provide a good overview of the many processes involved in building a dam. Many different types of dams are described in detail, including concrete and embankment dams. Hydrology and geology, important factors that need to be considered when choosing a suitable location, are also covered. The layout of the site is fairly good overall, but navigating the many sections and subsections can sometimes get confusing.

1997-01-01

290

Computing the stability and strength of rock foundations under concrete gravity dams  

Microsoft Academic Search

Conclusions  \\u000a \\u000a \\u000a \\u000a 1. \\u000a \\u000a Analysis of the studies and computations suggests that loss of stability due to shearing is characteristic for concrete gravity\\u000a dams constructed only on extremely weak rock and semirock foundations. On sound rock and rock of medium soundness, concrete\\u000a dams form a strong contact with the foundation and lose their stability if there is compressive failure of the foundation

Yu. A. Fishman

1976-01-01

291

Hungry Horse Dam`s successful selective withdrawal system  

SciTech Connect

Remodeled intake structures operating with computer precision at the Bureau of Reclamation`s Hungry Horse Dam hydropower plant in Montana now maintain downstream river water at its natural temperature levels. The intake structure uses a three-stage telescoping gate that allows warmer surface water to overflow and mix with the 38 degree bottom water. Test results from the first months of operation show success in warming the downstream water to its natural temperature, and studies are underway to measure the effect on targeted trout.

Christenson, D.J. [Dept. of Interior, Washington, DC (United States); Sund, R.L. [Bureau of Reclamation, Denver, CO (United States); Marotz, B.L. [Montana Department of Fish, Kalispell, MT (United States)

1996-05-01

292

Navajo Safety of Dams Project: Photographic Documentation of Round Rock Dam, Apache County, Arizona.  

National Technical Information Service (NTIS)

Round Rock Dam, located on the Navajo Reservation, was evaluated and determined eligible for nomination to the National Register of Historic Places as part of a safety of dams project. The dam is an off-stream, rolled, homogeneous earthfill embankment typ...

W. G. White

1994-01-01

293

Out, out, dam spot! The geomorphic response of rivers to dam removal.  

Treesearch

Description: About 75,000 irrigation, flood control, and hydropower dams in the ... as both a challenge and opportunity for river management and research. ... Reservoirs created by small dams are often completely filled with sediment and no ... In contrast, reservoirs behind large dams typically still store water and are only ...

294

To Dam Or Not To Dam: An Insight Into The Environmental Politics Of Rivers  

Microsoft Academic Search

In today's highly charged climate of environmental politics, decisions about building dams are extremely hard to make. Simply put, those who have the authority to make such decisions are damned if they dam and are also damned if they don't! There is no easy answer to many of the questions related to dam construction. No matter what the advantages of

Ashraf Ghaly; Megan Ferry

295

Uranium mill tailings and radon  

SciTech Connect

The major health hazard from uranium mill tailings is presumed to be respiratory cancer resulting from the inhalation of radon daughter products. A review of studies on inhalation of radon and its daughters indicates that the hazard from the tailings is extremely small. If the assumptions used in the studies are correct, one or two people per year in the US may develop cancer as a result of radon exhaled from all the Uranium Mill Tailings Remedial Action Program sites. The remedial action should reduce the hazard from the tailings by a factor of about 100.

Hanchey, L.A.

1981-01-01

296

Uranium mill tailings and radon  

SciTech Connect

The major health hazard from uranium mill tailings is presumed to be respiratory cancer resulting from the inhalation of radon daughter products. A review of studies on inhalation of radon and its daughters indicates that the hazard from the tailings is extremely small. If the assumptions used in the studies are correct, one or two people per year in the United States may develop cancer as a result of radon exhaled from all the Uranium Mill Tailings Remedial Action program sites. The remedial action should reduce the hazard from the tailings by a factor of about 100.

Hanchey, L.A.

1981-04-01

297

Defining Successful Dam Removal and Shifting the Focus of Restoration; A Midwest Perspective.  

NASA Astrophysics Data System (ADS)

The number of dam removals in the US has increased in the last decade because design lives are being exceeded for an increasing number of dams, and because interest groups have pushed for removal as part of attempts to restore river ecology. Large numbers of small dams have been removed, despite the paucity of information regarding the physical and biological impacts of removal. Here we offer a Midwestern perspective on dam removal, based on issues endemic to rivers of this region. In the absence of comprehensive national studies of dam removal, regionally specific studies provide a starting point for the debate over the efficacy of dam removal as a river restoration tool. Three of the most important issues in Midwestern river management are; excessive nutrient export, endangered mussel populations, and high sediment inputs. Some of the most diverse assemblages of freshwater mussels reside in the Midwest. These populations have been historically impacted by over-harvesting and increased sediment inputs to lotic environments. Dam removal results in two impacts that operate against mussel populations. First, the rapid dewatering of the upstream reservoir can cause nearly total mortality of the upstream (impoundment) community. Second, large volumes of sediment are released and deposited into downstream reaches, effectively smothering downstream communities. Sediment deposition downstream exacerbates the well-documented negative impacts that years of poor land use have had on stream and river biota, thus not only does deposition impact mussel communities, but interferes with all aquatic communities. Closely related to the movement of sediment out of the former impoundment is the export of nutrients. Issues of eutrophication have been documented in water bodies ranging from small receiving lakes to the Gulf of Mexico. Removing a dam releases nutrients that have been stored for the duration of the dam's existence, allowing them to flow downstream in a concentrated release that can last long after the initial removal. All three key Midwestern river management issues are directly impacted by the removal of dams. Though few comprehensive studies have quantified specific impacts following removal, information from chance failure observations and unpublished documentation can be used to support the argument that dam removal evaluation should move away from perceived needs, such as restoring connectivity and opening up habitat for non-endangered aquatic species, toward other relevant regional issues. Given the importance of excessive nutrient export, endangered mussel populations, and high sediment inputs, they should be substantial components in defining the potential success of removal as a restoration option in the Midwest, and possibly other areas of the US.

Selle, A. R.; Doyle, M. W.; Stanley, E. H.; Harbor, J. M.; Lyn, D. A.

2002-12-01

298

4. UPSTREAM ELEVATION VIEW OF BIG TUJUNGA DAM SHOWING THE ...  

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

4. UPSTREAM ELEVATION VIEW OF BIG TUJUNGA DAM SHOWING THE CONTROL HOUSE AND THE SPILLWAY BRIDGE AT THE ENDS OF THE DAM FACING WEST. - Big Tujunga Dam, 809 West Big Tujunga Road, Sunland, Los Angeles County, CA

299

View of upstream face of Lake Sabrina Dam showing the ...  

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

View of upstream face of Lake Sabrina Dam showing the redwood planks and base of dam from Lake Sabrina Basin, view north - Bishop Creek Hydroelectric System, Plant 2, Lake Sabrina Dam, Bishop Creek, Bishop, Inyo County, CA

300

3. VIEW, LOOKING NORTHEAST, SHOWING A SMALL FIELDSTONE DAM (KNOWN ...  

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

3. VIEW, LOOKING NORTHEAST, SHOWING A SMALL FIELD-STONE DAM (KNOWN LOCALLY AS DAM NO. 2), BUILT BY THE CCC - J. Clark Salyer National Wildlife Refuge Dams, Along Lower Souris River, Kramer, Bottineau County, ND

301

8. VIEW OF DAM 83, SHOWING OLD SOURIS RIVER CHANNEL ...  

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

8. VIEW OF DAM 83, SHOWING OLD SOURIS RIVER CHANNEL FROM THE DOWNSTREAM FACE OF THE DAM WITH POND A IN THE BACKGROUND, LOOKING SOUTH - Upper Souris National Wildlife Refuge, Dam 83, Souris River Basin, Foxholm, Ward County, ND

302

4. VIEW, LOOKING SOUTHWEST, SHOWING A LARGE FIELDSTONE DAM (KNOWN ...  

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

4. VIEW, LOOKING SOUTHWEST, SHOWING A LARGE FIELD-STONE DAM (KNOWN LOCALLY AS DAM NO. 1), BUILT BY THE CCC - J. Clark Salyer National Wildlife Refuge Dams, Along Lower Souris River, Kramer, Bottineau County, ND

303

GENERAL VIEW OF THE WILSON DAM, LOOKING SOUTHEAST, GENERATING PLANT ...  

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

GENERAL VIEW OF THE WILSON DAM, LOOKING SOUTHEAST, GENERATING PLANT IN THE BACKGROUND. - Wilson Dam & Hydroelectric Plant, Spanning Tennessee River at Wilson Dam Road (Route 133), Muscle Shoals, Colbert County, AL

304

Dam located to east of powerhouse, view from south. This ...  

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

Dam located to east of powerhouse, view from south. This dam holds back the waters of the Chattahoochee River to form the mill pond north of Riverdale Cotton Mill - Riverdale Cotton Mill, Powerhouse & Dam, Valley, Chambers County, AL

305

Geologic Setting of Mosul Dam and Its Engineering Implications.  

National Technical Information Service (NTIS)

The geologic setting of Mosul Dam is critically important for its engineering implications and its usefulness and contribution to engineering and operational decisions about the dam. The dam was constructed on alternating and highly variable units of gyps...

J. R. Kelley L. D. Wakeley S. W. Broadfoot M. L. Pearson C. A. McGrath

2007-01-01

306

77 FR 9265 - Glen Canyon Dam Adaptive Management Work Group  

Federal Register 2010, 2011, 2012, 2013

...INTERIOR Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY...SUMMARY: The Glen Canyon Dam Adaptive Management Work Group (AMWG...Secretary of the Interior concerning Glen Canyon Dam operations and other management...

2012-02-16

307

77 FR 67813 - Sam Rayburn Dam Project Power Rate  

Federal Register 2010, 2011, 2012, 2013

...Southwestern Power Administration Sam Rayburn Dam Project Power Rate AGENCY: Southwestern...existing power rate for the Sam Rayburn Dam Project (Rayburn), Rate Schedule SRD-08...Hydro Power and Energy Sold to Sam Rayburn Dam Electric Cooperative, Inc., for a...

2012-11-14

308

78 FR 7810 - Glen Canyon Dam Adaptive Management Work Group  

Federal Register 2010, 2011, 2012, 2013

...INTERIOR Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY...SUMMARY: The Glen Canyon Dam Adaptive Management Work Group (AMWG...Secretary of the Interior concerning Glen Canyon Dam operations and other management...

2013-02-04

309

76 FR 24516 - Glen Canyon Dam Adaptive Management Work Group  

Federal Register 2010, 2011, 2012, 2013

...INTERIOR Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY...SUMMARY: The Glen Canyon Dam Adaptive Management Work Group (AMWG...Secretary of the Interior concerning Glen Canyon Dam operations and other management...

2011-05-02

310

78 FR 21415 - Glen Canyon Dam Adaptive Management Work Group  

Federal Register 2010, 2011, 2012, 2013

...INTERIOR Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY...SUMMARY: The Glen Canyon Dam Adaptive Management Work Group (AMWG...Secretary of the Interior concerning Glen Canyon Dam operations and other management...

2013-04-10

311

77 FR 22801 - Glen Canyon Dam Adaptive Management Work Group  

Federal Register 2010, 2011, 2012, 2013

...INTERIOR Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY...SUMMARY: The Glen Canyon Dam Adaptive Management Work Group (AMWG...Secretary of the Interior concerning Glen Canyon Dam operations and other management...

2012-04-17

312

77 FR 43117 - Glen Canyon Dam Adaptive Management Work Group  

Federal Register 2010, 2011, 2012, 2013

...INTERIOR Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY...SUMMARY: The Glen Canyon Dam Adaptive Management Work Group (AMWG...Secretary of the Interior concerning Glen Canyon Dam operations and other management...

2012-07-23

313

78 FR 47695 - Sam Rayburn Dam Power Rate  

Federal Register 2010, 2011, 2012, 2013

...Southwestern Power Administration Sam Rayburn Dam Power Rate AGENCY: Southwestern Power Administration...SUMMARY: The current Sam Rayburn Dam Project rate was approved by the Federal...Southwestern has developed a proposed Sam Rayburn Dam rate to recover the required...

2013-08-06

314

4. VIEW SHOWING UPSTREAM FACE OF DAM, LOOKING NORTHEAST ...  

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

4. VIEW SHOWING UPSTREAM FACE OF DAM, LOOKING NORTHEAST - High Mountain Dams in Upalco Unit, Kidney Lake Dam, Ashley National Forest, 4.7 miles North of Miners Gulch Campground, Mountain Home, Duchesne County, UT

315

5. VIEW SHOWING DOWNSTREAM FACE AND TOE OF DAM, LOOKING ...  

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

5. VIEW SHOWING DOWNSTREAM FACE AND TOE OF DAM, LOOKING SOUTHWEST - High Mountain Dams in Upalco Unit, Kidney Lake Dam, Ashley National Forest, 4.7 miles North of Miners Gulch Campground, Mountain Home, Duchesne County, UT

316

3. OVERALL VIEW OF DAM, SHOWING UPSTREAM FACE, LOOKING EAST ...  

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

3. OVERALL VIEW OF DAM, SHOWING UPSTREAM FACE, LOOKING EAST - High Mountain Dams in Upalco Unit, Kidney Lake Dam, Ashley National Forest, 4.7 miles North of Miners Gulch Campground, Mountain Home, Duchesne County, UT

317

6. VIEW SHOWING DOWNSTREAM FACE AND TOE OF DAM, LOOKING ...  

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

6. VIEW SHOWING DOWNSTREAM FACE AND TOE OF DAM, LOOKING SOUTHWEST - High Mountain Dams in Upalco Unit, Kidney Lake Dam, Ashley National Forest, 4.7 miles North of Miners Gulch Campground, Mountain Home, Duchesne County, UT

318

5. DETAIL VIEW OF DAM, SHOWING TAINTER GATES, GATE PIERS ...  

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

5. DETAIL VIEW OF DAM, SHOWING TAINTER GATES, GATE PIERS AND DAM BRIDGE, WITH ROLLER GATE HEADHOUSES IN BACKGROUND, LOOKING NORTHWEST, UPSTREAM - Upper Mississippi River 9-Foot Channel, Lock & Dam No. 10, Guttenberg, Clayton County, IA

319

6. DETAIL VIEW OF DAM, SHOWING TAINTER GATES, GATE PIERS ...  

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

6. DETAIL VIEW OF DAM, SHOWING TAINTER GATES, GATE PIERS AND DAM BRIDGE, WITH ROLLER GATE HEADHOUSE IN BACKGROUND, LOOKING EAST, UPSTREAM - Upper Mississippi River 9-Foot Channel, Lock & Dam No. 10, Guttenberg, Clayton County, IA

320

4. DETAIL VIEW OF DAM, SHOWING TAINTER AND ROLLER GATES, ...  

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

4. DETAIL VIEW OF DAM, SHOWING TAINTER AND ROLLER GATES, GATE PIERS AND DAM BRIDGE, LOOKING SOUTHWEST, DOWNSTREAM - Upper Mississippi River 9-Foot Channel, Lock & Dam No. 10, Guttenberg, Clayton County, IA

321

Heavy-Tailed and Long-Tailed Distributions  

Microsoft Academic Search

\\u000a In this chapter we are interested in (right-) tail properties of distributions, i.e. in properties of a distribution which, for any x, depend only on the restriction of the distribution to (x,??). More generally it is helpful to consider tail properties of functions.

Sergey Foss; Dmitry Korshunov; Stan Zachary

322

76 FR 34799 - Permanent Dam Safety Modification at Cherokee, Fort Loudoun, Tellico, and Watts Bar Dams, TN  

Federal Register 2010, 2011, 2012, 2013

...TENNESSEE VALLEY AUTHORITY Permanent Dam Safety Modification at Cherokee, Fort Loudoun, Tellico, and Watts Bar Dams, TN AGENCY: Tennessee Valley Authority...permanent modifications to the existing dam facilities at Cherokee, Fort...

2011-06-14

323

78 FR 60271 - Hollow Dam Power Company; Ampersand Hollow Dam Hydro, LLC; Notice of Application for Transfer of...  

Federal Register 2010, 2011, 2012, 2013

...Regulatory Commission [Project No. 6972-032] Hollow Dam Power Company; Ampersand Hollow Dam Hydro, LLC; Notice of Application for Transfer...Motions To Intervene On September 10, 2013, Hollow Dam Power Company (transferor) and Ampersand...

2013-10-01

324

McNary Dam, Ice Harbor Dam, and Lower Monumental Dam Smolt Monitoring Program; 1996 Annual Report.  

SciTech Connect

The Washington Department of Fish & Wildlife (WDFW) assumed responsibility for the Smolt Monitoring Program at McNary Dam on the Columbia River in 1990 and at the new juvenile collection facility at Lower Monumental Dam on the Snake River in 1993. In 1996, Smolt Monitoring Program activities also began at the new juvenile collection facility located at Ice Harbor Dam. This report summarizes the 1996 Smolt Monitoring work at all three sites. The work at Ice Harbor consisted of Gas Bubble Trauma (GBT) monitoring only. In general, the 1996 passage season at both the McNary and Lower Monumental sites can be characterized by reduced passage of juveniles through the collection systems due to elevated river flows and spill, and low (<1%) overall facility mortality rates most likely resulting from cooler water temperatures. In accordance with the National Marine Fisheries Service recommendations (NMFS, 1995) all spring migrants were bypassed at McNary Dam in 1996. Mechanical problems within the McNary collection system resulted in collection and sampling activities being delayed until April 18 at this site, while sampling and collection began on the scheduled starting date of April 1 at Lower Monumental Dam. Monitoring operations were conducted through December 14 at McNary Dam and through October 28 at Lower Monumental Dam. An ongoing transportation evaluation summer migrant marking program was conducted at McNary Dam in 1996 by the NMFS. This necessitated the sampling of 394,211 additional fish beyond the recommended sampling guidelines. All total, 509,237 and 31,219 juvenile salmonids were anesthetized and individually counted, examined for scale loss, injuries, and brands by WDFW Smolt Monitoring personnel in 1996 at McNary Dam and Lower Monumental Dam, respectively.

Hillson, Todd; Lind, Sharon; Price, William (Washington Department of Fish and Wildlife, Olympia, WA)

1997-07-01

325

Dynamic Reservoir Interaction with Monticello Dam,  

National Technical Information Service (NTIS)

The study of arch dam-reservoir interaction is an outgrowth of a 4-year U.S.-China cooperative research project on 'Interaction Effects in the Seismic Response of Arch Dams.' Inconsistent comparisons were obtained in that project between measured and calc...

R. W. Clough X. F. Qui Y. Ghanaat

1987-01-01

326

Dams and Hydropower for Sustainable Development  

Microsoft Academic Search

The global debate about large dams is at once overwhelmingly complex and fundamentally simple. It is complex because the issues are not confined to the design, construction, and operation of dams themselves but embrace the range of social, environmental, and political choices on which the human aspiration to development and improved well being depend. Over the last two decades, global

I. Yüksel; E. K. Okedu

2009-01-01

327

EARTH DAM OVERTOPPING AND BREACH OUTFLOW  

Technology Transfer Automated Retrieval System (TEKTRAN)

Over the past half-century, the USDA has assisted in the design and construction of approximately 11,000 flood control and multipurpose dams. As these dams approach the end of their planned service life, sediment pools fill and sediment deposition in the flood pool reduces flood storage. Simultane...

328

Sand dams: Africa's answer to climate change?  

Microsoft Academic Search

In semi-arid regions of Africa, sand dam technology can make a significant contribution to mitigating the impacts of climate change by providing a low-cost solution to the problem of water conservation. Despite clear benefits, sand dams are used relatively little as they are very labour intensive, meaning a lack of effective community engagement can endanger project implementation and sustainability. Excellent

Simon Maddrell; Sophie Bown

329

Weighing a dam's economic and environmental impact  

Microsoft Academic Search

While some people claim that it was a publicity stunt or criticize it as an economic loss and a move in the wrong direction, the breaching of the low-slung Edwards Dam on July 1 has changed the landscape of the Kennebec River flowing through Augusta, Maine, and may also change the landscape for some other dammed rivers nationwide.The breaching marks

Randy Showstack

1999-01-01

330

The protein content of dental rubber dams  

Microsoft Academic Search

Objectives: The purpose of this study was to analyse the protein content of 17 commonly used rubber dams and to determine if they contained known allergenic proteins.Methods: Proteins were eluted with buffer from 17 brands of commercially available rubber dams. The quantity of eluted protein was measured and expressed in micrograms in every gram of rubber. The molecular weights of

K. M. Martin; M. V. Martin; A. J. Birss; E. A. Field

1997-01-01

331

Historic American Engineering Record, Stewart Mountain Dam.  

National Technical Information Service (NTIS)

The report provides a written narrative of the events leading to the construction of Stewart Mountain Dam on the Salt River, in Central Arizona. Stewart Mountain Dam was constructed by the Salt River Valley Water Users' Association between 1928 and 1930. ...

D. C. Jackson

1992-01-01

332

Historic American Engineering Record: Horseshoe Dam.  

National Technical Information Service (NTIS)

The report provides a written narrative of the events leading to the construction of Horseshoe Dam on the Verde River, in Central Arizona. Horseshoe Dam was constructed between 1944 and 1946 by the Salt River Valley Water Users' Association and the Phelps...

D. C. Jackson C. B. Fraser

1991-01-01

333

Earthquake-dammed lakes in New Zealand  

Microsoft Academic Search

Eleven small lakes were formed by landslides caused by the 1929 Buller earthquake; four others were formed by other historic earthquakes in New Zealand. At least nine other New Zealand lakes are also dammed by landslides and were probably formed by prehistoric earthquakes. When recognized by morphology, synchronous age, and areal distribution, earthquake-dammed lakes could provide an estimate of paleoseismicity

John Adams

1981-01-01

334

ROV-AIDED DAM INSPECTION: PRACTICAL RESULTS  

Microsoft Academic Search

Nowadays Unmanned Underwater Vehicles (UUVs) are used in a growing number of underwater missions, mostly inspections of different types of installations such as: telecommunication cables, pipes or oil extraction installations. A field where UUVs are still starting to prove their utility is dam inspection. This paper presents details our first approach in dam inspection. A set of experiments carried out

Joan Batlle; Tudor Nicosevici; Rafael Garcia; Marc Carreras

335

Teratoma in Human Tail Lipoma  

Microsoft Academic Search

We report a case of a rare congenital teratoma that developed in a lipoma attached to a remnant human tail. A male newborn baby presented with a large, 3-cm mass with an open margin, which pedunculated from a tail attached to the midline skin of the coccygeal area. Magnetic resonance images demonstrated multiple sacral spinal bifida without cord tethering, and

Se-Hyuck Park; Jee Soon Huh; Ki Hong Cho; Yong Sam Shin; Se Hyck Kim; Young Hwan Ahn; Kyung Gi Cho; Soo Han Yoon

2005-01-01

336

Human tail with spina bifida.  

PubMed

A true human tail is a rare occurrence and is defined as a caudal, vestigial, midline protrusion with skin covering connective tissue, muscle, vessels and nerves. We report a case of true human tail in a child, which is a very rare happening in humans. PMID:19922280

Chauhan, S P S; Gopal, N N; Jain, Mohit; Gupta, Anurag

2009-12-01

337

a Study on the Stability of Earth DAM Subjected to the Seismic Load  

NASA Astrophysics Data System (ADS)

For ensuring the earth dam's stability of Wangqingtuo reservoir when silt liquefaction happens during Tangshan earthquake, a large amount of laboratory soil tests and field measurements have been performed to obtain the mechanic properties of the soil and silt dynamic parameters. On the basis of the soil tests, the equivalent linear constitutive model is employed in the dynamic numerical simulation of the typical dam and the results indicate that the shear deformation is induced by the foundation liquefaction with the help of the geo-slope software. Moreover, the stability analysis is performed using the finite element elasto-plastic model that is considered the Mohr-Coulomb failure criteria to calculate the stability factor. The factors indicate the local instability would take place because of the shear action. At last, the measures are introduced to the designers for preventing the dam from the instability.

Qi, Jinghua; Che, Ailan; Ge, Xiurun

338

Groundwater Forecasting Optimization Pertain to Dam Removal  

NASA Astrophysics Data System (ADS)

There is increasing interest in removing dams due to changing ecological and societal values. Groundwater recharge rate is closely connected to reservoir presence or absence. With the removal of dams and their associated reservoirs, reductions in groundwater levels are likely to impact water supplies for domestic, industrial and agricultural use. Therefore accessible economic and time effective tools to forecast groundwater level declines with acceptable uncertainty following dam removals are critical for public welfare and healthy regional economies. These tools are also vital to project planning and provide beneficial information for restoration and remediation managements. The standard tool for groundwater forecasting is 3D Numerical modeling. Artificial Neural Networks (ANNs) may be an alternative tool for groundwater forecasting pertain to dam removal. This project compared these two tools throughout the Milltown Dam removal in Western Montana over a five year period. It was determined that ANN modeling had equal or greater accuracy for groundwater forecasting with far less effort and cost involved.

Brown, L.; Berthelote, A. R.

2011-12-01

339

[Limnetic zooplankton run-off a high-head dam and their fate in a river with high current velocity (case of the Krasnoiarsk hydroelectric power station on the Yenisei river].  

PubMed

The vertical distribution of net zooplankton in head-water of Krasnoyarsk hydroelectric power station and its horizontal distribution in the tail-water were studied during two years in winter and summer seasons. In order to distinguish living and dead individuals the special staining was used. It was revealed that on average 77% of living plankton pass through high-head dam with deep water scoop to the tailwater. While passing through dam aggregates some individuals of the reservoir plankton are traumatized and die, that results in some increase of portion of dead individuals in the tail water near dam (from 3 to 6%). Alive zooplankton passed through the dam aggregates is eliminated under the Upper Yenisei highly turbulent conditions. There is approximately 10% of it in 32 km from the dam if compare with biomass in 20-40 m layer of reservoir, the portion of dead increases to 11%. The biomass of zooplankton suspended in the water column of the tail-water sometimes increases (till > 1 g/m3) due to large Copepoda Heteroscope borealis, which inhabits near-bottom and near-shore river zones and can be found in the central part of the river during reproductive period. Limnetic zooplankton from the reservoir cannot be considered as important food for planktivores in the tail-water. PMID:15032067

Dubovskaia, O P; Gladyshev, M I; Makhutova, O N

340

Application of parallel computing to seismic damage process simulation of an arch dam  

NASA Astrophysics Data System (ADS)

The simulation of damage process of high arch dam subjected to strong earthquake shocks is significant to the evaluation of its performance and seismic safety, considering the catastrophic effect of dam failure. However, such numerical simulation requires rigorous computational capacity. Conventional serial computing falls short of that and parallel computing is a fairly promising solution to this problem. The parallel finite element code PDPAD was developed for the damage prediction of arch dams utilizing the damage model with inheterogeneity of concrete considered. Developed with programming language Fortran, the code uses a master/slave mode for programming, domain decomposition method for allocation of tasks, MPI (Message Passing Interface) for communication and solvers from AZTEC library for solution of large-scale equations. Speedup test showed that the performance of PDPAD was quite satisfactory. The code was employed to study the damage process of a being-built arch dam on a 4-node PC Cluster, with more than one million degrees of freedom considered. The obtained damage mode was quite similar to that of shaking table test, indicating that the proposed procedure and parallel code PDPAD has a good potential in simulating seismic damage mode of arch dams. With the rapidly growing need for massive computation emerged from engineering problems, parallel computing will find more and more applications in pertinent areas.

Zhong, Hong; Lin, Gao; Li, Jianbo

2010-06-01

341

Numerical analysis of earthquake response of an ultra-high earth-rockfill dam  

NASA Astrophysics Data System (ADS)

Failure of high earth dams under earthquake may cause disastrous economic damage and loss of lives. It is necessary to conduct seismic safety assessment, and numerical analysis is an effective way. Solid-fluid interaction has a significant influence on the dynamic responses of geotechnical materials, which should be considered in the seismic analysis of earth dams. The initial stress field needed for dynamic computation is often obtained from postulation, without considering the effects of early construction and reservoir impounding. In this study, coupled static analyses are conducted to simulate the construction and impounding of an ultra-high earth rockfill dam in China. Then based on the initial static stress field, dynamic response of the dam is studied with fully coupled nonlinear method. Results show that excess pore water pressure accumulates gradually with earthquake and the maximum value occurs at the bottom of core. Acceleration amplification reaches the maximum at the crest as a result of whiplash effect. Horizontal and vertical permanent displacements both reach the maximum values at the dam crest.

Dong, W. X.; Xu, W. J.; Yu, Y. Z.; Lv, H.

2013-05-01

342

[A case of human tail].  

PubMed

A human tail is a rare anatomical curiosity. A case of a human tail associated with lipomyelomeningocele is reported. The made subject was born, by breech delivery, at the 39th-week with a 3,008 g body weight. He was admitted to our hospital because of the presence of a human tail and subcutaneous mass in the midline lumbosacral region. The tail was about 7.5 cm in length and 2 cm in diameter. It was elastic and covered by normal skin. No systemic anomaly was found. Spina bifida below L5 was revealed, and no bony shadow was found on the plain X-ray film. CT scan showed a low density area in the spinal canal between L3 and lower sacral region that extended into the tail through the spina bifida. MRI also revealed intraspinal long T2 mass which was attached to the spinal cord and extended into the tail. Myelogram indicated intradural extramedullary mass below the L3 level. Surgical treatment was performed on the 3rd month of life with a diagnosis of a human tail with lipomyelomeningocele. At surgery, the tail was found to consist mainly of lipomatous tissue which extended subcutaneously and entered the spinal canal through the spina bifida. The tail and subcutaneous lipomatous tissue were totally excised. The capsule of subcutaneous lipomatous tissue was followed circumferentially down into the spinal canal, and found to be transformed to arachnoid membrane. Intradural lipomatous tissue was excised piece by piece, leaving only a small remnant attached to the conus medullaris to preserve sacral nerve root function.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2000165

Yamatani, K; Saitoh, T; Oi, M; Oka, N; Endoh, T; Takaku, A

1991-01-01

343

Dams and the fish fauna of the Neotropical region: impacts and management related to diversity and fisheries.  

PubMed

Reservoirs have been built in almost all of the hydrographic basins of Brazil. Their purposes include water supply for cities, irrigation and mainly, generation of electricity. There are more than 700 large dams and associated reservoirs in the large rivers of the country. These reservoirs favor local and regional economic development, but they also bring serious and irreversible alterations in the natural hydrologic regime of rivers, affecting habitat quality and the dynamics of the biota. In the impounded area, the main impact is the change from lotic to lentic water, which influences aquatic fauna, including fishes. Impacts of reservoirs present relevant spatiotemporal variations. Immediately after reservoir formation, fish species richness usually increases due to incorporation of surrounding habitats, but richness decreases as reservoirs age. However, impacts downstream of dams appear to be similar or stronger than those that occur within the reservoir. Dams promote discharge control, altering the seasonal cycles of floods. These effects are augmented when dams are constructed in cascades. Therefore, dams profoundly influence composition and structure of fish assemblages. Most affected species are the rheophilics and long distance migratory that require distinct habitats to fulfill their life cycles. Populations of migratory species may collapse or even disappear in intensely regulated stretches. Management actions taken to minimize impacts of dams in Brazil historically considered construction of fish passages, fishery control and stocking. The results of these actions are questionable and/or with clear failures. In this paper, we give emphasis to the Paraná River basin, the most affected by dams in Brazil. We describe some patterns in the alteration and decline in fish diversity in areas influenced by dams. We also discuss negative consequences in the fishery and ecosystems functioning. Finally, we argue the relevance and the success of the management actions taken and present some suggestions to improve conservation of the ichthyofauna in South American basins influenced by dams. PMID:19197482

Agostinho, A A; Pelicice, F M; Gomes, L C

2008-11-01

344

Anisotropy for spatial summation of elongated patches of grating: a tale of two tails.  

PubMed

Studies of spatial summation often use sinusoidal gratings with blurred edges. When the envelope is elongated (i) along the grating stripes and (ii) at right angles to the grating stripes, we refer to the stimuli as skunk-tails and tiger-tails respectively. Previous work [Polat & Tyler, 1999; Vision Research, 39, 887-895.] has found that sensitivity to skunk-tails is greater than for tiger-tails, but there have been several failures to replicate this result within a subset of the conditions. To address this we measured detection thresholds for skunk-tails, tiger-tails and squares of grating with sides matched to the lengths of the tails. For foveal viewing, we found a contrast sensitivity advantage in the order of 2dB for skunk-tails over tiger-tails, but only for horizontal gratings. For vertical gratings, sensitivity was very similar for both tail-types. When the stimuli were presented parafoveally (upper right visual field), a small advantage was found for skunk-tails over tiger-tails at both orientations, and spatial summation slopes were close to that of the ideal observer. We did not replicate the findings of Polat & Tyler, but our results are consistent with (i) those of Foley et al. [Foley, J. M., Varadharajan, S., Koh, C. C., & Farias, C. Q. (2007) Vision Research, 47, 85-107.] who used only vertical gratings and (ii) those from modelfest, where only horizontal gratings were used. The small effect of tail-type here suggests an anisotropy in the underlying physiology. PMID:17512570

Meese, Tim S; Hess, Robert F

2007-05-18

345

Influence of Dams on Downstream Beaches: Eressos, Lesbos, Eastern Mediterranean  

Microsoft Academic Search

Small water storage dams are nowadays regarded as the ideal solution for the water-thirsty islands of the Greek Archipelago. Several of these dams have been already constructed and more are planned for the near future. However, dams can also create problems to coastal areas, particularly to the beaches found at the lower reaches of the dammed rivers. The present contribution

A. F. Velegrakis; M. I. Vousdoukas; O. Andreadis; G. Adamakis; E. Pasakalidou; R. Meligonitis; G. Kokolatos

2008-01-01

346

Guidelines for Assessing Sediment-Related Effects of DAM Removal  

Microsoft Academic Search

Dam removal is becoming more common in the United States as dams age and environmental concerns increase. Sediment management is an important part of many dam removal projects, but there are no commonly accepted methods to assess the level of risk associated with sediment stored behind dams. Therefore, the interagency Subcommittee on Sedimentation (SOS) is sponsoring the development of a

B. P. Greimann; T. Randle; J. Bountry

2010-01-01

347

Intelligent early-warning system of dam safety  

Microsoft Academic Search

For the effective control of dam life process, it is important to implement the real-time diagnosis and reasonable evaluation for dam safety based on prototype observations. The development of intelligent early-warning systems of dam safety (IEWSDS) is a significant approach to realize above aim. This paper regarded dam as a vital and intelligent system, thereby constructed a bionics model of

Huai-Zhi Su; Zhi-Ping Wen

2005-01-01

348

Seismic upgrade of hydraulic fill dam by buttressing  

Microsoft Academic Search

The vulnerability of hydraulic fill dams under strong earthquake shaking has long been recognized. When located in areas of high seismic hazard, seismic upgrading of these types of dams is often required to meet current dam safety standards. Selection of an appropriate design concept for seismic upgrading of such dams requires careful consideration of seismically induced deformations when the hydraulic

L. H. Mejia; J. I. Sun; K. K. Leung

2005-01-01

349

9. VIEW OF BASIN BEHIND DAM, SHOWING SCARS FROM EARTH ...  

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

9. VIEW OF BASIN BEHIND DAM, SHOWING SCARS FROM EARTH MOVING TO CONSTRUCT DAM, LOOKING EAST - High Mountain Dams in Upalco Unit, East Timothy Lake Dam, Ashley National Forest, 8.4 miles North of Swift Creek Campground, Mountain Home, Duchesne County, UT

350

8. VIEW OF BASIN BEHIND DAM, SHOWING SCARS FROM EARTH ...  

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

8. VIEW OF BASIN BEHIND DAM, SHOWING SCARS FROM EARTH MOVING TO CONSTRUCT DAM, LOOKING NORTH - High Mountain Dams in Upalco Unit, East Timothy Lake Dam, Ashley National Forest, 8.4 miles North of Swift Creek Campground, Mountain Home, Duchesne County, UT

351

7. SOUTHEAST VIEW OF BIG DALTON DAM SHOWING THE MULTIPLE ...  

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

7. SOUTHEAST VIEW OF BIG DALTON DAM SHOWING THE MULTIPLE ARCHES, AN UPSTREAM VIEW OF THE PARAPET WALL ALONG THE CREST OF THE DAM, AND THE SHELTER HOUSE AT THE EAST END OF THE DAM. - Big Dalton Dam, 2600 Big Dalton Canyon Road, Glendora, Los Angeles County, CA

352

43. Credit TR. Reconstruction of Dam No. 4 after 1936 ...  

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

43. Credit TR. Reconstruction of Dam No. 4 after 1936 flood. Pouring concrete for new dam section; opening at left for flume to remove water from behind coffer dam. Photo c. 1936 - Dam No. 4 Hydroelectric Plant, Potomac River, Martinsburg, Berkeley County, WV

353

8. WEST DAM, LOOKING DUE NORTH OVER TOP OF WEST ...  

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

8. WEST DAM, LOOKING DUE NORTH OVER TOP OF WEST DAM, SHOWING RELATIONSHIP BETWEEN OUTLET TO RIGHT OF DAM, NEW PUMP PLANT BUILDING AND CANAL TO LEFT OF DAM. - Eastside Reservoir, Diamond & Domenigoni Valleys, southwest of Hemet, Hemet, Riverside County, CA

354

4. VIEW OF DOWNSTREAM FACE OF DAM, WITH SCARS FROM ...  

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

4. VIEW OF DOWNSTREAM FACE OF DAM, WITH SCARS FROM EARTH MOVING TO CONSTRUCT DAM IN FOREGROUND, LOOKING NORTHWEST - High Mountain Dams in Upalco Unit, Five Point Lake Dam, Ashley National Forest, 12 miles Northwest of Swift Creek Campground, Mountain Home, Duchesne County, UT

355

2. Overview of the Lost River Diversion Dam House complex ...  

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

2. Overview of the Lost River Diversion Dam House complex taken from west edge of horseshoe-shaped Lost River Diversion Dam. Interior of east side of dam in the foreground. Facing East. - Klamath Basin Project, Lost River Diversion Dam House, Lost River near intersection of State Highway 140 & Hill Road, Klamath Falls, Klamath County, OR

356

53. AVALON DAM Photographic copy of historic photo, August ...  

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

53. AVALON DAM - Photographic copy of historic photo, August 9, 1893 (original print located at the Carlsbad Irrigation District offices, Carlsbad, New Mexico) photographer unknown 'EDDY DAM. LOOKING EAST.' VIEW OF COLLAPSED DAM - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

357

66. AVALON DAM Photographic copy of historic photo, May ...  

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

66. AVALON DAM - Photographic copy of historic photo, May 22, 1908 (original print filed in Record Group 115, National Archives, Washington, D.C.) W.J.Lubken, photographer 'VIEW LOOKING EAST FROM WEST END OF AVALON DAM, SHOWING DOWNSTREAM FACE OF DAM' - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

358

46. Photocopy of photograph, c. 1933. VIEW OF DAM AND ...  

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

46. Photocopy of photograph, c. 1933. VIEW OF DAM AND FOREBAY. NOTE ALL WATER FLOWING THROUGH FOREBAY AND OUT EITHER TAILRACE OR SLUICE GATE (INSTEAD OF OVER DAM) BECAUSE OF LOW WATER FLOW. (Courtesy of the Potomac Edison Company Library (Hagerstown, MD), Historical Data Files, Dam No. 5 listing - Dam No. 5 Hydroelectric Plant, On Potomac River, Hedgesville, Berkeley County, WV

359

6. DAM AFTERBAY, WITH OWYEE RIVER IN FOREGROUND, SHOWING OUTLET ...  

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

6. DAM AFTERBAY, WITH OWYEE RIVER IN FOREGROUND, SHOWING OUTLET TUNNEL PORTAL (LEFT) AND POWERHOUSE AND ENTRANCE PORTAL TO DAM INTERIOR (RIGHT). NOTE RELEASE OF WATER FROM NEEDLE VALVE NUMBER 2 IN VALVEHOUSE ON DAM. VIEW TO SOUTHEAST. - Owyhee Dam, Across Owyhee River, Nyssa, Malheur County, OR

360

Assessing Sediment-Related Effects of Dam Removals  

Microsoft Academic Search

Subcommittee on Sedimentation: Sediment Management and Dam Removal Workshop; Portland, Oregon, 14-16 October 2008; For a host of reasons including dam safety, maintenance costs, and ecological concerns, more dams are currently being removed each year in the United States than are being constructed. Because many reservoirs have accumulated sediments within their pools, dam removal can potentially impose a variety of

J. Rose Wallick; Timothy Randle

2009-01-01

361

Implications of Dam Obstruction for Global Freshwater Fish Diversity  

Microsoft Academic Search

Dams are obstructing rivers worldwide, impairing habitat and migration opportunities for many freshwater fish species; however, global data linking dam and fish distributions have been limited. Here, we quantify dam obstruction at the biogeographic scale of freshwater ecoregion, which provides the spatial framework necessary to assess the risk of fish species loss due to dams and allows us to identify

Catherine Reidy Liermann; Christer Nilsson; James Robertson; Rebecca Y. Ng

2012-01-01

362

Concrete dam on the Bratsk hydroelectric station  

SciTech Connect

The Bratsk concrete dam was designed and constructed with a sufficient degree of reliability. Settlement of the dam together with the powerhouse developed uniformly under the entire foundation. Two irreversible processes causing aging of the dam have been established by operating observations: leaching of the concrete and decompression of the contact zone of the foundation near the upstream face of the powerhouse sections. The decompression is due to the fact that the powerhouse sections are lighter than the spillway sections. At the present level this process can only be slowed by the combined use of grouting and drainage unloading.

Solov'eva, Z.I.

1988-07-01

363

Sustainability of dams-an evaluation approach  

NASA Astrophysics Data System (ADS)

Situated in the stream bed of a river, dams and reservoirs interrupt the natural hydrological cycle. They are very sensitive to all kinds of changes in the catchment, among others global impacts on land use, climate, settlement structures or living standards. Vice versa dams strongly affect the spatially distributed, complex system of ecology, economy and society in the catchment both up- and downstream of the reservoir. The occurrence of negative impacts due to large dams led to serious conflicts about future dams. Nevertheless, water shortages due to climatic conditions and their changes, that are faced by enormous water and energy demands due to rising living standards of a growing world population, seem to require further dam construction, even if both supply and demand management are optimised. Although environmental impact assessments are compulsory for dams financed by any of the international funding agencies, it has to be assumed that the projects lack sustainability. Starting from an inventory of today's environmental impact assessments as an integral part of a feasibility study the presentation will identify their inadequacies with regard to the sustainability of dams. To improve the sustainability of future dams and avoid the mistakes of the past, the planning procedures for dams have to be adapted. The highly complex and dynamical system of interrelated physical and non-physical processes, that involves many different groups of stakeholders, constitutes the need for a model-oriented decision support system. In line with the report of the World Commission of Dams an integrated analysis and structure of the complex interrelations between dams, ecology, economy and society will be presented. Thus the system, that a respective tool will be based on, is analysed. Furthermore an outlook will be given on the needs of the potential users of a DSS and how it has to be embedded in the overall planning process. The limits of computer-based decision-support in the very specific context of dam construction will be identified. Special focus will be on the constraints arising from the need to jointly evaluate qualitative and quantitative aspects and the methodological potential of multi-criteria evaluation in this respect.

Petersson, E.

2003-04-01

364

Methane release below a tropical hydroelectric dam  

NASA Astrophysics Data System (ADS)

Tropical reservoirs upstream from hydroelectric dams are known to release significant amounts of methane to the atmosphere. Here we demonstrate that methane emissions downstream from hydroelectric dams can also be large. Emissions of CH4 downstream of Balbina reservoir in the central Amazon basin (Brazil) were calculated from regular measurements of degassing in the outflow of the turbines and downstream diffusive losses. Annual emissions from the reservoir surface and downstream from the dam were 34 and 39 Gg C, respectively. The downstream emission alone represented the equivalent of 3% of all methane released from central Amazon floodplain.

Kemenes, Alexandre; Forsberg, Bruce Rider; Melack, John Michael

2007-06-01

365

Molecular requirements for the formation of a kinetochore-microtubule interface by Dam1 and Ndc80 complexes  

PubMed Central

Kinetochores are large protein complexes that link sister chromatids to the spindle and transduce microtubule dynamics into chromosome movement. In budding yeast, the kinetochore–microtubule interface is formed by the plus end–associated Dam1 complex and the kinetochore-resident Ndc80 complex, but how they work in combination and whether a physical association between them is critical for chromosome segregation is poorly understood. Here, we define structural elements required for the Ndc80–Dam1 interaction and probe their function in vivo. A novel ndc80 allele, selectively impaired in Dam1 binding, displayed growth and chromosome segregation defects. Its combination with an N-terminal truncation resulted in lethality, demonstrating essential but partially redundant roles for the Ndc80 N-tail and Ndc80–Dam1 interface. In contrast, mutations in the calponin homology domain of Ndc80 abrogated kinetochore function and were not compensated by the presence of Dam1. Our experiments shed light on how microtubule couplers cooperate and impose important constraints on structural models for outer kinetochore assembly.

Lampert, Fabienne; Mieck, Christine; Alushin, Gregory M.; Nogales, Eva

2013-01-01

366

Effect of Porcine Circovirus Type 2 (PCV2) Vaccination of the Dam on PCV2 Replication In Utero  

Microsoft Academic Search

The aims of this study were to determine if porcine circovirus type 2 (PCV2) vaccination of the dam is effective in preventing fetal PCV2 infection and reproductive failure. Twelve pregnant, PCV2-naïve sows were randomly divided into four groups, with three sows in each group. Group 1 sows served as noninoculated, nonvaccinated negative controls, group 2 sows were vaccinated with a

D. M. Madson; A. R. Patterson; S. Ramamoorthy; N. Pal; X. J. Meng; T. Opriessnig

2009-01-01

367

Transient water and sediment storage of the decaying landslide dams induced by the 2008 Wenchuan earthquake, China  

NASA Astrophysics Data System (ADS)

Earthquake-triggered landslide dams are potentially dangerous disrupters of water and sediment flux in mountain rivers, and capable of releasing catastrophic outburst flows to downstream areas. We analyze an inventory of 828 landslide dams in the Longmen Shan mountains, China, triggered by the Mw 7.9 2008 Wenchuan earthquake. This database is unique in that it is the largest of its kind attributable to a single regional-scale triggering event: 501 of the spatially clustered landslides fully blocked rivers, while the remainder only partially obstructed or diverted channels in steep watersheds of the hanging wall of the Yingxiu-Beichuan Fault Zone. The size distributions of the earthquake-triggered landslides, landslide dams, and associated lakes (a) can be modeled by an inverse gamma distribution; (b) show that moderate-size slope failures caused the majority of blockages; and (c) allow a detailed assessment of seismically induced river-blockage effects on regional water and sediment storage. Monte Carlo simulations based on volumetric scaling relationships for soil and bedrock failures respectively indicate that 14% (18%) of the estimated total coseismic landslide volume of 6.4 (14.6) × 109 m3 was contained in landslide dams, representing only 1.4% of the > 60,000 slope failures attributed to the earthquake. These dams have created storage capacity of ~ 0.6 × 109 m3 for incoming water and sediment. About 25% of the dams containing 2% of the total river-blocking debris volume failed one week after the earthquake; these figures had risen to 60% (~ 20%), and > 90% (> 90%) within one month, and one year, respectively, thus also emptying ~ 92% of the total potential water and sediment storage behind these dams within one year following the earthquake. Currently only ~ 0.08 × 109 m3 remain available as natural reservoirs for storing water and sediment, while ~ 0.19 × 109 m3, i.e. about a third of the total river-blocking debris volume, has been eroded by rivers. Dam volume and upstream catchment area control to first order the longevity of the barriers, and bivariate domain plots are consistent with the observation that most earthquake-triggered landslide dams were ephemeral. We conclude that the river-blocking portion of coseismic slope failures disproportionately modulates the post-seismic sediment flux in the Longmen Shan on annual to decadal timescales.

Fan, Xuanmei; van Westen, Cees J.; Korup, Oliver; Gorum, Tolga; Xu, Qiang; Dai, Fuchu; Huang, Runqiu; Wang, Gonghui

2012-10-01

368

heterogeneous long-tailed sources  

Microsoft Academic Search

In this paper we consider a generalization of the so-called model where types of long-tailed sessions enter a buffer . The instantaneous rates of the sessions are functions of the occupancy of an system with long-tailed distributions. In particular we assume that a session of type transmits cells per unit time and lasts for a ran- dom time with long

Nikolay Likhanov; Ravi R. Mazumdar

369

Water-quality study of proposed reregulation dam downstream of Wolf Creek Dam, Cumberland River, Kentucky. Final report  

Microsoft Academic Search

This report describes the application of an unsteady, one-dimensional water-quality model to the Cumberland River below Wolf Creek Dam, Kentucky. A hydropower upgrade of Wolf Creek Dam and construction of a reregulation dam, located approximately 10 miles below Wolf Creek Dam, are under consideration. Simulations were conducted under unreregulated conditions and projected conditions following impoundment to provide information concerning the

1986-01-01

370

Toward Policies and Decision-Making for Dam Removal  

Microsoft Academic Search

Dam removal has emerged as a critical issue in environmental management. Agencies responsible for dams face a drastic increase\\u000a in the number of potential dam removals in the near future. Given limited resources, these agencies need to develop ways to\\u000a decide which dams should be removed and in what order. The underlying science of dam removal is relatively undeveloped and

MARTIN W. DOYLE; JON M. HARBOR; EMILY H. STANLEY

2003-01-01

371

Vallecito Dam Flow Measurement and Weir Calibration.  

National Technical Information Service (NTIS)

Recent modifications to the Vallecito Dam outlet works structure have caused increased turbulence near the outlet works flow measurement device, making flow measurements unreliable. In addition, no accurate measure of flow through the spillway radial gate...

R. George

1994-01-01

372

Wynoochee Dam and Lake, Wynoochee River, Washington.  

National Technical Information Service (NTIS)

The Wynoochee Project in Grays Harbor County of southwestern Washington involves construction of a central concrete gravity dam 663 feet long and 175 feet high for the associated purposes of water supply, irrigation, flood control, recreation and fisherie...

1971-01-01

373

The Hoover Dam: Lonely Lands Made Fruitful  

NSDL National Science Digital Library

Project designer Janet Haven of the University of Virginia American Studies Program presents the construction of the Hoover Dam as an alternative narrative to the devastation of the Great Depression in her photoessay, The Hoover Dam: Lonely Lands Made Fruitful. Five slide shows created in Flash2 cover the construction from diverting the Colorado River to pouring concrete and adding the final touches to a completed dam. The slide shows are prefaced by historical background, including short essays on topics such as the Dam as the "Machine in the Desert" and the text of Franklin D. Roosevelt's Dedication Speech upon completion, September 30, 1935. Images of maps and plans are linked throughout, and a list of Works Consulted gives concise source descriptions as well as ideas for further reading.

1998-01-01

374

Historic American Engineering Record, Theodore Roosevelt Dam.  

National Technical Information Service (NTIS)

Roosevelt Dam comprises the key structure in one of the first major federally sponsored reclamation project in the West. Authorized as one of the Reclamation Service's first projects in 1903, it continues to store water for agricultural lands, homeowners,...

D. C. Jackson

1992-01-01

375

Hydraulic Model Study of Brantley Dam Spillway.  

National Technical Information Service (NTIS)

Hydraulic model studies on the spillway at Brantley Dam in New Mexico confirmed the design of the spillway, slotted bucket energy dissipator, and the spillway tailwater channel. Side piers at the spillway entrance were modified to improve spillway flow; a...

E. R. Zeigler

1987-01-01

376

Earthquake-dammed lakes in New Zealand  

SciTech Connect

Eleven small lakes were formed by landslides caused by the 1929 Buller earthquake; four others were formed by other historic earthquakes in New Zealand. At least nine other New Zealand lakes are also dammed by landslides and were probably formed by prehistoric earthquakes. When recognized by morphology, synchronous age, and areal distribution, earthquake-dammed lakes could provide an estimate of paleoseismicity for the past few hundred or thousand years.

Adams, J.

1981-05-01

377

Leibis/Lichte Dam in Germany  

NASA Astrophysics Data System (ADS)

In Thuringia the second highest dam of Germany is under construction (figure 1). The new Leibis/Lichte dam is a 370 m long and 102.5 m high gravity dam of concrete with straight axis. With the completion of the Leibis/Lichte dam in 2005 more than 300.000 inhabitants of the Eastern Regions of Thuringia will be supplied with high quality drinking water. The foundation rocks at the dam site are exclusively greyish-blue argillaceous schist, silt schist and cleaved fine sandstones from the Ordovician period (phycode schist). The main joint system consists of three differently orientated joints. Geomechanically of main interest is the shallow dipping bedding, especially in the left abutment because of its downhill dip. The other joints show a generally steep dip. Wide extending faults with thick mylonites or fractured zones, which could influence the foundation of the dam, do not exist within the dam site. The engineering geological field mapping of the foundation surface confirms the rock mass parameters. The excavation works are carried out in four different stages to avoid loosening of the foundation rock. Great care is taken to assure that the foundation rock is protected against weathering. Based on the results of preliminary investigations the foundation level was planned in a depth of 4 to14 m. The abutments of the dam correspond to the expectations. Predominantly the argillaceous rock shows a low permeability. The permeability is exclusively linked to faults respectively few large joints. In order to prevent seepage and to reduce the uplift pressure, a grout curtain in two rows is arranged with a depth of 5 to 44 metres.

Kühnel, Markus

378

Distributional Impacts of Large Dams in China  

NASA Astrophysics Data System (ADS)

Dams on a river are believed to have heterogeneous impacts to the upstream, local and downstream areas. Generally, irrigation dams will bring benefits to the downstream by facilitating more irrigation, while it will bring negative impacts to upstream due to inundation or no impact to local area as a combination result of population dislocation and economic benefits. This paper checked the impacts of large dams (above 100 meters) on the upstream, downstream and local area, using 2000-2008 county level data in China. Robust heterogeneous impacts of different categories of dams (mainly dams serving for irrigation, hydropower, or other purposes) were found on different areas, using IV regression approaches. Dams higher than 100 meters are significantly and heterogeneously impacting agricultural production, urban employment and rural per capita income. Its beneficial impact on agriculture production is significant for downstream especially in continuous drought years. But its impacts on social welfare indicators, such as primary school enrollment and hospital beds, are not heterogeneously different across regions.

Bao, X.

2010-12-01

379

Geophysical investigations of geology and structure at the Martis Creek Dam, Truckee, California  

USGS Publications Warehouse

A recent evaluation of Martis Creek Dam highlighted the potential for dam failure due to either seepage or an earthquake on nearby faults. In 1972, the U.S. Army Corps of Engineers constructed this earthen dam, located within the Truckee Basin to the north of Lake Tahoe, CA for water storage and flood control. Past attempts to raise the level of the Martis Creek Reservoir to its design level have been aborted due to seepage at locations downstream, along the west dam abutment, and at the base of the spillway. In response to these concerns, the U.S. Geological Survey has undertaken a comprehensive suite of geophysical investigations aimed at understanding the interplay between geologic structure, seepage patterns, and reservoir and groundwater levels. This paper concerns the geologic structure surrounding Martis Creek Dam and emphasizes the importance of a regional-scale understanding to the interpretation of engineering-scale geophysical data. Our studies reveal a thick package of sedimentary deposits interbedded with Plio-Pleistocene volcanic flows; both the deposits and the flows are covered by glacial outwash. Magnetic field data, seismic tomography models, and seismic reflections are used to determine the distribution and chronology of the volcanic flows. Previous estimates of depth to basement (or the thickness of the interbedded deposits) was 100 m. Magnetotelluric soundings suggest that electrically resistive bedrock may be up to 2500 m deep. Both the Polaris Fault, identified outside of the study area using airborne LiDAR, and the previously unnamed Martis Creek Fault, have been mapped through the dam area using ground and airborne geophysics. Finally, as determined by direct-current resistivity imaging, time-domain electromagnetic sounding, and seismic refraction, the paleotopography of the interface between the sedimentary deposits and the overlying glacial outwash plays a principal role both in controlling groundwater flow and in the distribution of the observed seepage.

Bedrosian, P. A.; Burton, B. L.; Powers, M. H.; Minsley, B. J.; Phillips, J. D.; Hunter, L. E.

2012-01-01

380

Geophysical investigations of geology and structure at the Martis Creek Dam, Truckee, California  

NASA Astrophysics Data System (ADS)

A recent evaluation of Martis Creek Dam highlighted the potential for dam failure due to either seepage or an earthquake on nearby faults. In 1972, the U.S. Army Corps of Engineers constructed this earthen dam, located within the Truckee Basin to the north of Lake Tahoe, CA for water storage and flood control. Past attempts to raise the level of the Martis Creek Reservoir to its design level have been aborted due to seepage at locations downstream, along the west dam abutment, and at the base of the spillway. In response to these concerns, the U.S. Geological Survey has undertaken a comprehensive suite of geophysical investigations aimed at understanding the interplay between geologic structure, seepage patterns, and reservoir and groundwater levels. This paper concerns the geologic structure surrounding Martis Creek Dam and emphasizes the importance of a regional-scale understanding to the interpretation of engineering-scale geophysical data. Our studies reveal a thick package of sedimentary deposits interbedded with Plio-Pleistocene volcanic flows; both the deposits and the flows are covered by glacial outwash. Magnetic field data, seismic tomography models, and seismic reflections are used to determine the distribution and chronology of the volcanic flows. Previous estimates of depth to basement (or the thickness of the interbedded deposits) was 100 m. Magnetotelluric soundings suggest that electrically resistive bedrock may be up to 2500 m deep. Both the Polaris Fault, identified outside of the study area using airborne LiDAR, and the previously unnamed Martis Creek Fault, have been mapped through the dam area using ground and airborne geophysics. Finally, as determined by direct-current resistivity imaging, time-domain electromagnetic sounding, and seismic refraction, the paleotopography of the interface between the sedimentary deposits and the overlying glacial outwash plays a principal role both in controlling groundwater flow and in the distribution of the observed seepage.

Bedrosian, Paul A.; Burton, Bethany L.; Powers, Michael H.; Minsley, Burke J.; Phillips, Jeffrey D.; Hunter, Lewis E.

2012-02-01

381

Mercury and other trace elements in soils affected by the mine tailing spill in Aznalcóllar (SW Spain)  

Microsoft Academic Search

The Aznalcóllar accident (28th April 1998) occurred because the collapse of the tailing-dam dike of the Aznalcóllar–Los Frailes mines. Soils were affected by a slurry of acidic water loaded with trace elements, finely divided metal sulphides, and materials used in the refining \\/floating process. Studies carried out before and after the soil restoration activities (sludge removal, amending, tilling, and afforestation)

F. Cabrera; J. Ariza; P. Madejón; E. Madejón; J. M. Murillo

2008-01-01

382

Evaluation of major constraints to revegetation of lead/zinc mine tailings using bioassay techniques.  

PubMed

The residues from the extraction of lead/zinc (Pb/Zn) ores of most Pb/Zn mines are permanently stored in tailings ponds, which require revegetation to reduce their environmental impact. This can only be done if the main constraints on plant establishment are evaluated. This can readily be done by field and greenhouse studies. To test this, the properties of different tailings from Lechang Pb/Zn mine located at the north of Guangdong Province in southern China have been studied. Physical and chemical properties including concentrations of metals (Pb, Zn, Cd and Cu) in the tailings and soils collected from different sites have been measured. The results showed that tailings contain low nitrogen (0.016-0.075%), low-organic matter (0.58-1.78%), high salt (3.55-13.85 dS/m), and high total and diethylene-tetramine-pentaacetic acid (DTPA)-extractable metal concentrations (total: 1,019-1,642 microg g(-1) Pb, 3,078-6,773 microg g(-1) Zn, 8-23 microg g(-1) Cd, and 85-192 microg g(-1) Cu; DTPA-extractable: 59-178 microig g(-1) Pb, 21-200 microg g(-1) Zn, 0.30-1.5 mcirog g(-1) Cd, and 4.3-12 microg g(-1) Cu). Aqueous extracts of tailings/soils (10%, 20% and 30%, w/v) from different sites were prepared for testing their effects on seed germination and root elongation of a vegetable crop Brassica chinensis and a grass species Cynodon dactylon. It was found that root elongation provided a better evaluation of toxicity than seed germination. The ranking of toxicity using root elongation was: high-sulfur tailings > tailing dam > sparsely vegetated tailings > densely vegetated tailings > mountain soil for both plants. This order was consistent with DTPA-extractable Pb contents in the tailings and soils. B. chinensis seedlings were then grown in the mixtures of different proportions of tailings and farm soil for 4 weeks, and the results (dry weights of seedlings) were in line with the root elongation test. All these demonstrated that heavy metal toxicity, especially available Pb, low content of nutrient, and poor physical structure were major constraints on plant establishment and colonization on the Pb/Zn mine tailings. PMID:12137044

Ye, Z H; Shu, W S; Zhang, Z Q; Lan, C Y; Wong, M H

2002-06-01

383

Wavelet analysis of the hydrologic effects of Glen Canyon Dam on the Colorado River at Lees Ferry, Arizona  

NASA Astrophysics Data System (ADS)

Continuous wavelet transformation is a powerful analytical tool with which to analyze the hydrologic effects of dam construction and operation on river systems, an issue of great managerial, political, and social interest in the western United States. Using continuous records of instantaneous discharge from the Lees Ferry gaging station and records of daily mean discharge from upstream tributaries, we conducted a continuous wavelet transformation (CWT) analysis of the pre- and post-dam hydrologic structure of the Colorado River in Grand Canyon, downstream from Glen Canyon Dam. CWT of mean daily discharge provided a highly compressed and integrative picture of the near-total elimination of pronounced annual and sub-annual wavelet features after dam construction. Events such as droughts, managed floods, and uncontrollable snowmelt-driven discharge were also visible. The continuous record, interpolated to consistent hourly intervals, revealed a much finer scale image of river conditions. Prior to dam construction, the CWT showed the influence of warm season peak discharge periods, discharge driven by the monsoon and dissipating tropical storms, and annual droughts. In the post-dam period, strong wavelet signals related to diurnal power generation, weekly shutdowns in power generation, shifts in daily discharge management, and the 1996 experimental flood were dominant. The CWT approach appears to represent well-known features of dam operation without generation of spurious results. Thus, CWT, with quantitative statistical significance tests, should be a promising tool for assessing (1) dam operation in less well-studied regions and (2) real-time success or failure of management attempts to reconstruct desired flow characteristics.

White, M. A.; Schmidt, J. C.; Topping, D. J.

2003-12-01

384

DAMS, DAM REMOVAL, AND RIVER RESTORATION: A HEDONIC PROPERTY VALUE ANALYSIS  

Microsoft Academic Search

This article presents the results of a hedonic property value analysis for multiple hydropower sites along the Kennebec River in Maine, including the former site of the Edwards Dam in Augusta, Maine. The effect of the removal of the Edwards Dam on the Kennebec River in Maine is examined through consumer’s marginal willingness to pay to be close to or

LYNNE Y. LEWIS; CURTIS BOHLEN; SARAH WILSON

2008-01-01

385

Dam nation: A geographic census of American dams and their large-scale hydrologic impacts  

Microsoft Academic Search

Newly available data indicate that dams fragment the fluvial system of the continental United States and that their impact on river discharge is several times greater than impacts deemed likely as a result of global climate change. The 75,000 dams in the continental United States are capable of storing a volume of water almost equaling one year's mean runoff, but

William L. Graf

1999-01-01

386

Sediment quality in Rio Guadiamar (SW, Spain) after a tailing dam collapse: Contamination, toxicity and bioavailability  

Microsoft Academic Search

An integrated assessment of sediment quality in the Guadiamar River after a mining spill was conducted. The concentration of different metals and other conventional parameters were measured in sediments located along the river. Four sediment toxicity tests (Hyalella azteca 28-day survival and growth test; Chironomus riparius 10-day survival and growth test; Hexagenia spp. 21-day survival and growth test; and Tubifex

Inmaculada Riba; T. Angel DelValls; Trefor B. Reynoldson; Danielle Milani

2006-01-01

387

Magnetohydrodynamics of Mira's cometary tail  

NASA Astrophysics Data System (ADS)

Aims: The asymptotic giant-branch, long-period variable star Mira exhibits a 4 parsec long cometary tail in the far-ultraviolet. We address the issue of the origin of this structure and its emission process by simulating the transition of this star from the interstellar medium to the Local Bubble, which is a tenuous, high-pressure medium. Methods: We use the hydrodynamic and the magnetohydrodynamic modules of the PLUTO astrophysical code to carry out our simulations. We study the system without a cooling function, with a simplified exponential cooling function, and with a simplified nonequilibrium cooling function. Results: We find evidence that magnetohydrodynamics constrain the shape of the cometary tail and explain features of its far-ultraviolet emission. We suggest an emission process that involves C0 excitation through inelastic electron collisions and a two-photon continuum to explain the luminosity of Mira's tail.

Gómez, E. A.

2013-10-01

388

Migration of arsenic from old tailings ponds-A case study on the King Edward Mine, Cornwall, UK  

SciTech Connect

A methodology is presented to study the physico-chemical processes in old tailings ponds using an array of analytical-physical chemistry approaches. A case study was conducted on the sorption/desorption behaviour of arsenic in tailings pond 2406, at the King Edward Mine (KEM) in Cornwall, UK. The tailings pond was in operation from approximately 1907 to 1921. The methodology involves two principal stages: (1) sequential extraction followed by subsequent arsenic species determination to characterise the material with regards to the association of arsenic with soil phases and identification of As (III/V) in the easily accessible soil phase; (2) batch contacting/equilibrating the tailings pond material with As(III/V), followed by a similar procedure as in stage 1 to establish the material's As(III/V) phase distribution kinetics/thermodynamics. By extrapolating the data from present day samples we infer past and future elemental mobility. From this study it is concluded that adsorption and desorption from tailings material is a rapid process for the most unstable soil phases (non-specific and specific) and a slow process for the more stable phases (poorly crystalline and well crystalline). The hypothetical application of this conclusion to the tailings from dam 2406 is that, during the initial phases of the dam's creation (ca. 100 years ago), when arsenic was both in solution and bound to mineralogical components, arsenic must have dispersed into the environment as a result of slow As(V) adsorption/phase distribution processes. Aging of the tailings material sees the movement of the arsenic to the more stable soil phases, producing a situation that is seen at present day.

Beeston, Michael Philip [National Institute of Chemistry (Kiribati), Hajdrihova 19, SI-1001 Ljubljana (Slovenia); University of Exeter in Cornwall (UEC), Tremough Campus, TR10 9EZ Penryn, Cornwall (United Kingdom)], E-mail: Michael.Beeston@ki.si; Tuen van Elteren, Johannes [National Institute of Chemistry (Kiribati), Hajdrihova 19, SI-1001 Ljubljana (Slovenia); Slejkovec, Zdenka [Jozef Stefan Institute (JSI), Jamova 39, SI-1000 Ljubljana (Slovenia); Glass, Hylke Jan [University of Exeter in Cornwall (UEC), Tremough Campus, TR10 9EZ Penryn, Cornwall (United Kingdom)

2008-09-15

389

From light tails to heavy tails through multiplier  

Microsoft Academic Search

Let X and Y be two independent nonnegative random variables, of which X has a distribution belonging to the class or for some ????0 and Y is unbounded. We study how their product XY inherits the tail behavior of X. Under some mild technical assumptions we prove that the distribution of XY belongs to the class or accordingly. Hence, the

Qihe Tang

2008-01-01

390

Productive Failure  

ERIC Educational Resources Information Center

|This study demonstrates an existence proof for "productive failure": engaging students in solving complex, ill-structured problems without the provision of support structures can be a productive exercise in failure. In a computer-supported collaborative learning setting, eleventh-grade science students were randomly assigned to one of two…

Kapur, Manu

2008-01-01

391

Transition from EcoDam to T4Dam DNA recognition mechanism without loss of activity and specificity.  

PubMed

The EcoDam and T4Dam DNA-(adenine N6)-methyltransferases both methylate the adenine residue in GATC sites. These enzymes are highly related in amino acid sequence, but they deviate in their contact to the first base pair of the target sequence. EcoDam contacts Gua1 with K9 (which corresponds to T4Dam A6), while T4Dam contacts Gua1 with R130 (which corresponds to EcoDam Y138). We have "transplanted" the T4Dam DNA recognition into EcoDam and show that the EcoDam K9A/Y138R double mutant is highly active and specific. We also studied the intermediates of this transition: The EcoDam K9A variant showed low activity and loss of recognition of Gua1 [Horton, et al., J. Mol. Biol. 2006, 358, 559-570]. In contrast, the EcoDam Y138R variant, which carries both Gua1 recognition elements (K9 from EcoDam and R138 corresponding to R130 from T4Dam), is fully active and specific. This result indicates that a smooth evolutionary pathway exists for changing the EcoDam DNA recognition mode to T4Dam without loss of activity and without generation of evolutionary intermediates with reduced activity. We consistently observed increased activity of EcoDam variants containing Y138R; this suggests that the transition from EcoDam (Gua1 recognition through K9) to T4Dam (Gua1 recognition through R130) was driven by selective pressure towards increased catalytic activity. PMID:19725089

Elsawy, Hany; Podobinschi, Sveatoslav; Chahar, Sanjay; Jeltsch, Albert

2009-10-12

392

Methodology for the calculation of annualized incremental risks in systems of dams.  

PubMed

In the past few years, the field of dam safety has approached risk informed methodologies throughout the world and several methodologies and programs are appearing to aid in the systematization of the calculations. The most common way of implementing these calculations is through the use of event trees, computing event probabilities, and incremental consequences. This methodology is flexible enough for several situations, but its generalization to the case of systems of several dams is complex and its implementation in a completely general calculation methodology presents some problems. Retaining the event tree framework, a new methodology is proposed to calculate incremental risks. The main advantage of this proposed methodology is the ease with which it can be applied to systems of several dams: with a single risk model that describes the complete system and with a single calculation the incremental risks of the system can be obtained, being able to allocate the risk of each dam and of each failure mode. The article shows how both methodologies are equivalent and also applies them to a case study. PMID:21175718

Serrano-Lombillo, Armando; Escuder-Bueno, Ignacio; de Membrillera-Ortuño, Manuel G; Altarejos-García, Luis

2010-12-22

393

Toward policies and decision-making for dam removal.  

PubMed

Dam removal has emerged as a critical issue in environmental management. Agencies responsible for dams face a drastic increase in the number of potential dam removals in the near future. Given limited resources, these agencies need to develop ways to decide which dams should be removed and in what order. The underlying science of dam removal is relatively undeveloped and most agencies faced with dam removal lack a coherent purpose for removing dams. These shortcomings can be overcome by the implementation of two policies by agencies faced with dam removal: (1) the development and adoption of a prioritization scheme for what constitutes an important dam removal, and (2) the establishment of minimum levels of analysis prior to decision-making about a dam removal. Federal and state agencies and the scientific community must encourage an initial experimental phase of dam removal during which only a few dams are removed, and these are studied intensively. This will allow for the development of the fundamental scientific understanding needed to support effective decision-making in the future and minimize the risk of disasters arising from poorly thought out dam removal decisions. PMID:12677292

Doyle, Martin W; Harbor, Jon M; Stanley, Emily H

2003-04-01

394

Channel changes downstream from a dam  

USGS Publications Warehouse

A flood-control dam was completed during 1979 on Bear Creek, a small tributary stream to the South Platte River in the Denver, Colorado, area. Before and after dam closure, repetitive surveys between 1977 and 1992 at five cross sections downstream of the dam documented changes in channel morphology. During this 15-year period, channel width increased slightly, but channel depth increased by more than 40 percent. Within the study reach, stream gradient decreased and median bed material sizes coarsened from sand in the pools and fine gravel on the riffle to a median coarse gravel throughout the reach. The most striking visual change was from a sparse growth of streamside grasses to a dense growth of riparian woody vegetation.

Hadley, R. F.; Emmett, W. W.

1998-01-01

395

117. Maricopa Dam Water System, Electric Transmission Lines, Catwalk, Derrick ...  

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

117. Maricopa Dam Water System, Electric Transmission Lines, Catwalk, Derrick at Elev. +65. October 15, 1934. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

396

6. VIEW NORTHEAST, WEST END OF DAM DURING CONSTRUCTION OF ...  

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

6. VIEW NORTHEAST, WEST END OF DAM DURING CONSTRUCTION OF FISHWAY, DECEMBER 1995, SHOWING REMOVAL OF PLANKING - Norwich Water Power Company, Dam, West bank of Shetucket River opposite Fourteenth Street, Greenville section, Norwich, New London County, CT

397

5. VIEW SHOWING THE DOWNSTREAM SIDE OF SWAN FALLS DAM ...  

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

5. VIEW SHOWING THE DOWNSTREAM SIDE OF SWAN FALLS DAM AND POWER HOUSE, LOOKING UPSTREAM TO SOUTH FROM THE A MOUND OF DEBRIS ABOUT THIRTY TO FORTY FEET ABOVE THE RIVER - Swan Falls Dam, Snake River, Kuna, Ada County, ID

398

5. VIEW NORTHWEST ON SHELTON SIDE OF DAM. SHELTON GATEHOUSE ...  

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

5. VIEW NORTHWEST ON SHELTON SIDE OF DAM. SHELTON GATEHOUSE AND LOCK STRUCTURE. - Ousatonic Water Power Company, Dam & Canals, CT Routes 34 & 108, 1 mile North of Derby-Shelton Bridge, Derby, New Haven County, CT

399

7. Detail view of reinforced concrete archrings comprising dam's upstream ...  

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

7. Detail view of reinforced concrete arch-rings comprising dam's upstream face. Impressions of the wooden formwork used in construction are visible in the concrete. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

400

23. VIEW OF HORSE MESA DAM, SHOWING SPILLWAY DISCHARGE TUNNEL ...  

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

23. VIEW OF HORSE MESA DAM, SHOWING SPILLWAY DISCHARGE TUNNEL AT LEFT, RIGHT (OR NORTH) SPILLWAY, HEFU POWER UNIT, AND ORIGINAL POWER PLANT - Horse Mesa Dam, Salt River, 65 miles East of Phoenix, Phoenix, Maricopa County, AZ

401

68. LITTLE ROCK AND PALMDALE IRRIGATION DISTRICT, LITTLE ROCK DAM: ...  

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

68. LITTLE ROCK AND PALMDALE IRRIGATION DISTRICT, LITTLE ROCK DAM: STRESS SHEET, SHEET 4; MAY, 1918. Littlerock Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

402

71. PALMDALE WATER COMPANY, EASTWOOD MULTIPLEARCHED DAM: STRESS SHEET, SHEET ...  

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

71. PALMDALE WATER COMPANY, EASTWOOD MULTIPLE-ARCHED DAM: STRESS SHEET, SHEET 3; DECEMBER 20, 1918. Littlerock Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

403

44. LOCK AND DAM NO. 26 (REPLACEMENT). LOCK LOCK ...  

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

44. LOCK AND DAM NO. 26 (REPLACEMENT). LOCK -- LOCK GUIDEWALLS -DOWNSTREAM GUIDEWALL, PARTIAL ISOMETRIC VIEW. M-L 26(R) 26/40 - Upper Mississippi River 9-Foot Channel Project, Lock & Dam 26R, Alton, Madison County, IL

404

18. DAM, DETAIL PLAN OF SERVICE BRIDGE, GENERAL PLAN AND ...  

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

18. DAM, DETAIL PLAN OF SERVICE BRIDGE, GENERAL PLAN AND ELEVATION. September 1936 - Mississippi River 9-Foot Channel Project, Lock & Dam No. 17, Upper Mississippi River, New Boston, Mercer County, IL

405

1. SNAKE RIVER VALLEY IRRIGATION DISTRICT DAM, VIEW OF NORTH ...  

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

1. SNAKE RIVER VALLEY IRRIGATION DISTRICT DAM, VIEW OF NORTH ELEVATION OF INTAKE ON EAST SIDE OF DAM - Snake River Valley Irrigation District, East Side of Snake River (River Mile 796), Shelley, Bingham County, ID

406

8. Early stage of power house construction at Dam No. ...  

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

8. Early stage of power house construction at Dam No. 4, showing two stiff leg derricks used to excavate limestone for power house building. Photo c. 1907. Credit PEM. - Dam No. 4 Hydroelectric Plant, Potomac River, Martinsburg, Berkeley County, WV

407

19. Downstream face of Mormon Flat Dam completed. Power plant ...  

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

19. Downstream face of Mormon Flat Dam completed. Power plant is nearing completion. Photographer unknown, 1926. Source: Salt River Project. - Mormon Flat Dam, On Salt River, Eastern Maricopa County, east of Phoenix, Phoenix, Maricopa County, AZ

408

20. View of Mormon Flat Dam, power plant, and reservoir. ...  

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

20. View of Mormon Flat Dam, power plant, and reservoir. Photographer unknown, 1926. Source: Salt River Project. - Mormon Flat Dam, On Salt River, Eastern Maricopa County, east of Phoenix, Phoenix, Maricopa County, AZ

409

VIEW FROM NORTH BANK LOOKING SOUTHWEST SHOWING DAM CREST, FISH ...  

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

VIEW FROM NORTH BANK LOOKING SOUTHWEST SHOWING DAM CREST, FISH ATTRACTION FLOW STRUCTURE (LEFT) AND WASTE FLOW GATE OUTLET (RIGHT) - Trout Creek Dam, River Mile 1.8 on Trout Creek, Carson, Skamania County, WA

410

View of Lake Sabrina Dam showing the wooden planks along ...  

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

View of Lake Sabrina Dam showing the wooden planks along the upstream side face and the spillway at the right center of photo, view north - Bishop Creek Hydroelectric System, Plant 2, Lake Sabrina Dam, Bishop Creek, Bishop, Inyo County, CA

411

View of upstream face of Lake Sabrina Dam showing redwood ...  

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

View of upstream face of Lake Sabrina Dam showing redwood planks and boulders in Lake Sabrina Basin, view north - Bishop Creek Hydroelectric System, Plant 2, Lake Sabrina Dam, Bishop Creek, Bishop, Inyo County, CA

412

87. DAM TAINTER GATE OPERATING MACHINERY TRAVELING HOIST ...  

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

87. DAM - TAINTER GATE OPERATING MACHINERY - TRAVELING HOIST - AMERICAN TYPE ASSEMBLY (ML-5-55/111-FS), February 1938 - Upper Mississippi River 9-Foot Channel Project, Lock & Dam No. 5, Minneiska, Winona County, MN

413

"No. 190. Grand Valley Diversion Dam. Diversion gates, water flowing ...  

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

"No. 190. Grand Valley Diversion Dam. Diversion gates, water flowing into high line. June, 1917. R.B.D." - Grand Valley Diversion Dam, Half a mile north of intersection of I-70 & Colorado State Route 65, Cameo, Mesa County, CO

414

70. Downstream view of Waddell Dam spillway and taintor gates. ...  

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

70. Downstream view of Waddell Dam spillway and taintor gates. Photographer Mark Durben. Source: Salt River Project. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

415

44. Reinforcement construction to Pleasant Dam. Photographer unknown, 1935. Source: ...  

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

44. Reinforcement construction to Pleasant Dam. Photographer unknown, 1935. Source: Huber Collection, University of California, Berkeley, Water Resources Library. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

416

50. Upstream face of Humbug Creek Diversion Dam showing sluice ...  

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

50. Upstream face of Humbug Creek Diversion Dam showing sluice opening. Photographer James Eastwood, 1986. Source: Salt River Project. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

417

39. Pleasant Dam from east abutment with spillway visible at ...  

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

39. Pleasant Dam from east abutment with spillway visible at center. Photographer unknown, 1927. Source: MWD. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

418

7. Aggregate operations downstream from dam. Photographer unknown, March 1924. ...  

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

7. Aggregate operations downstream from dam. Photographer unknown, March 1924. Source: Salt River Project. - Mormon Flat Dam, On Salt River, Eastern Maricopa County, east of Phoenix, Phoenix, Maricopa County, AZ

419

45. Reinforcement work to buttresses at Pleasant Dam. Support work ...  

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

45. Reinforcement work to buttresses at Pleasant Dam. Support work for roadway and roadway visible. Photographer unknown, 1935. Source: Huber Collection. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

420

56. Upstream face of diversion dam looking east. Headgates are ...  

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

56. Upstream face of diversion dam looking east. Headgates are partially visible at far left. Photographer Mark Durben, 1986. Source: Salt River Project. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

421

57. Downstream side of left section of diversion dam. Photographer ...  

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

57. Downstream side of left section of diversion dam. Photographer Mark Durben, 1986. Source: Salt River Project. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

422

60. Waddell Dam in relation and spillway tailrace. Photographer Mark ...  

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

60. Waddell Dam in relation and spillway tailrace. Photographer Mark Durben, 1986. Source: Salt River Project. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

423

49. Downstream face of Humbug Creek Diversion Dam with sluice ...  

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

49. Downstream face of Humbug Creek Diversion Dam with sluice opening at center. Photographer James Eastwood, 1986. Source: Salt River Project. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

424

1. Site of Mormon Flat Dam looking upstream. Photographer unknown, ...  

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

1. Site of Mormon Flat Dam looking upstream. Photographer unknown, 1923. Source: Salt River Project. - Mormon Flat Dam, On Salt River, Eastern Maricopa County, east of Phoenix, Phoenix, Maricopa County, AZ

425

40. Reservoir behind Pleasant Dam, looking downstream, spillway is at ...  

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

40. Reservoir behind Pleasant Dam, looking downstream, spillway is at right. Photographer unknown, c. late 1920s. Source: MWD. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

426

55. Downstream face of diversion dam looking northwest. Photographer Mark ...  

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

55. Downstream face of diversion dam looking northwest. Photographer Mark Durben, 1986. Source: Salt River Project. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

427

36. CROSS SECTIONAL VIEW OF ORIGINAL HORSE MESA DAM POWER ...  

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

36. CROSS SECTIONAL VIEW OF ORIGINAL HORSE MESA DAM POWER PLANT, LOOKING NORTH. ONLY TWO OF THE THREE UNITS ARE VISIBLE - Horse Mesa Dam, Salt River, 65 miles East of Phoenix, Phoenix, Maricopa County, AZ

428

32. Otter Lake Dam. View from downstream show how the ...  

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

32. Otter Lake Dam. View from downstream show how the dam blends into its environment. Looking east-northeast. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

429

34. DOWNSTREAM VIEW OF COOLIDGE DAM COMPLETED. POWER HOUSE, INTAKE ...  

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

34. DOWNSTREAM VIEW OF COOLIDGE DAM COMPLETED. POWER HOUSE, INTAKE TOWERS, WEST SPILLWAY CHANNEL AND DECORATIVE EAGLES ALL CLEARLY VISIBLE, c. 1928 - Coolidge Dam, Gila River, Peridot, Gila County, AZ

430

1. VIEW SHOWING CONTRACTOR'S CAMP AND BARTLETT DAM IN THE ...  

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

1. VIEW SHOWING CONTRACTOR'S CAMP AND BARTLETT DAM IN THE DISTANCE. THE CONTRACTOR'S MESS HALL, COMMISSARY, RECREATIONAL HALL, DORMITORIES, CAMP HOSPITAL, AND WORKMEN'S COTTAGES ARE ALSO SHOWN. February 20, 1939 - Bartlett Dam, Verde River, Phoenix, Maricopa County, AZ

431

4. VIEW OF DAM, SHOWING TAINTER GATE PIERS, TAINTER GATE ...  

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

4. VIEW OF DAM, SHOWING TAINTER GATE PIERS, TAINTER GATE NO. 1 SERVICE BRIDGE, AND LOCOMOTIVE CRANE, LOOKING NORTHEAST (UPSTREAM) - Upper Mississippi River Nine-Foot Channel Project, Lock & Dam No. 25, Cap au Gris, Lincoln County, MO

432

5. VIEW OF DAM, SHOWING TAINTER GATE PIERS, TAINTER GATE ...  

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

5. VIEW OF DAM, SHOWING TAINTER GATE PIERS, TAINTER GATE NO. 1, AND SERVICE BRIDGE, LOOKING SOUTHEAST (DOWNSTREAM) - Upper Mississippi River Nine-Foot Channel Project, Lock & Dam No. 25, Cap au Gris, Lincoln County, MO

433

4. Aerial view of Whitsett intake (lower right), Parker Dam ...  

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

4. Aerial view of Whitsett intake (lower right), Parker Dam and village (left), Gene Wash Reservoir, Gene Pump Plant and village (right). - Parker Dam, Spanning Colorado River between AZ & CA, Parker, La Paz County, AZ

434

10. DETAIL VIEW OF SPILLWAY AT DAM 83, SHOWING RIVER ...  

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

10. DETAIL VIEW OF SPILLWAY AT DAM 83, SHOWING RIVER COBBLE PAVING (FOREGROUND) AND WINGWALL, LOOKING EAST - Upper Souris National Wildlife Refuge, Dam 83, Souris River Basin, Foxholm, Ward County, ND

435

9. VIEW OF SPILLWAY AT DAM 83, SHOWING LOCATION OF ...  

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

9. VIEW OF SPILLWAY AT DAM 83, SHOWING LOCATION OF FORMER CONCRETE FLASHBOARD STRUCTURE ON RIGHT, LOOKING WEST - Upper Souris National Wildlife Refuge, Dam 83, Souris River Basin, Foxholm, Ward County, ND

436

1. VIEW OF DAM 83, LOOKING SOUTHWEST FROM THE LOOKOUT ...  

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

1. VIEW OF DAM 83, LOOKING SOUTHWEST FROM THE LOOKOUT TOWER AT THE REFUGE HEADQUARTERS (see HAER No. ND-3-A-13 for comparison) - Upper Souris National Wildlife Refuge, Dam 83, Souris River Basin, Foxholm, Ward County, ND

437

18. REMNANTS OF PORTION OF DAM THAT SERVED AS FEEDER ...  

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

18. REMNANTS OF PORTION OF DAM THAT SERVED AS FEEDER CANAL, WITH OUTER WALL OF LOCK AT RIGHT (April 1979) - Hamilton Street Dam, Lehigh River upstream of Hamilton Street Bridge, Allentown, Lehigh County, PA

438

61. 'LITTLEROCK DAM LOOKING FROM LEFT TO RIGHT ABUTMENTSPILLWAY ...  

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

61. 'LITTLEROCK DAM - LOOKING FROM LEFT TO RIGHT ABUTMENT-SPILLWAY DISCHARGING.' No date; probably 1960s. Photographer unknown. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

439

27. Evening view of downstream face of Pleasant Dam under ...  

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

27. Evening view of downstream face of Pleasant Dam under construction. Part of construction camp housing is visible in foreground. Photographer unknown, 1927. Source: MWD. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

440

15. SOUTH SIDE OF DAM SHOWING BAFFLE PIERS AT FOOT ...  

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

15. SOUTH SIDE OF DAM SHOWING BAFFLE PIERS AT FOOT OF SPILLWAY TO LEFT AND PARTIAL VIEW OF BUTTRESSES AND SIDEWALKS TO RIGHT. - Pit 4 Diversion Dam, Pit River west of State Highway 89, Big Bend, Shasta County, CA

441

View of powerhouse and dam from third floor of original ...  

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

View of powerhouse and dam from third floor of original section of Langdale Cotton Mill, looking northeast - Langdale Cotton Mill, Powerhouse & Dam, 5910 Nineteenth Avenue, Valley, Chambers County, AL

442

A dam in the middle of a river  

NSDL National Science Digital Library

Dams have negative impacts on the plants and animals that have adapted to the specific movement of natural rivers and streams. Dams also cause temperature changes, erosion, and movement of sediment that are deadly to many organisms.

Katie Hale (California State University, Fullerton;Student, Biological Sciences)

2007-01-12

443

6. EASTERLY VIEW OF BIG DALTON DAM SHOWING THE SHELTER ...  

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

6. EASTERLY VIEW OF BIG DALTON DAM SHOWING THE SHELTER HOUSE IN THE BACKGROUND. PHOTO TAKEN FROM THE ACCESS ROAD LEADING TO THE CONTROL HOUSE. - Big Dalton Dam, 2600 Big Dalton Canyon Road, Glendora, Los Angeles County, CA

444

2. SOUTHEAST VIEW OF BIG TUJUNGA DAM SHOWING THE LEFT ...  

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

2. SOUTHEAST VIEW OF BIG TUJUNGA DAM SHOWING THE LEFT ABUTMENT WITH THE CONTROL HOUSE IN THE BACKGROUND. PHOTO TAKEN FROM THE ACCESS ROAD. - Big Tujunga Dam, 809 West Big Tujunga Road, Sunland, Los Angeles County, CA

445

PALMDALE WATER COMPANY, LITTLE ROCK DAM: REINFORCEMENT, SECTION THROUGH ARCH ...  

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

PALMDALE WATER COMPANY, LITTLE ROCK DAM: REINFORCEMENT, SECTION THROUGH ARCH RING, AMENDED SHEET 6; SEPTEMBER, 1922. Palmdale Water District files - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

446

97. DAM TAINTER GATE OPERATING MACHINERY TRAVELING HOIST ...  

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

97. DAM - TAINTER GATE OPERATING MACHINERY - TRAVELING HOIST - AMERICAN TYPE ASSEMBLY (ML-4-55/111-FS), February 1938 - Upper Mississippi River 9-Foot Channel, Lock & Dam No. 4, Alma, Buffalo County, WI

447

100. DAM TAINTER GATE OPERATING MACHINERY AMERICAN HOIST ...  

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

100. DAM - TAINTER GATE OPERATING MACHINERY - AMERICAN HOIST CAR ELECTRIFICATION ASSEMBLY (ML-4-55/146), January 1958 - Upper Mississippi River 9-Foot Channel, Lock & Dam No. 4, Alma, Buffalo County, WI

448

98. DAM TAINTER GATE OPERATING MACHINERY TRAVELING HOIST ...  

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

98. DAM - TAINTER GATE OPERATING MACHINERY - TRAVELING HOIST - AMERICAN TYPE ASSEMBLY (ML-4&5-55/112-FS), March 1934 - Upper Mississippi River 9-Foot Channel, Lock & Dam No. 4, Alma, Buffalo County, WI

449

2. EASTSIDE RESERVOIR UNDER CONSTRUCTION LOOKING WEST WITH EAST DAM ...  

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

2. EASTSIDE RESERVOIR UNDER CONSTRUCTION LOOKING WEST WITH EAST DAM IN MIDDLE GROUND, WEST DAM IN DISTANCE. - Eastside Reservoir, Diamond & Domenigoni Valleys, southwest of Hemet, Hemet, Riverside County, CA

450

94. DAM TAINTER GATE OPERATING MACHINERY METHOD OF ...  

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

94. DAM - TAINTER GATE OPERATING MACHINERY - METHOD OF ATTACHING LIFTING CHAINS TO DRUMS OF HOIST - LAKESIDE TYPE (ML-4&5-55/34-FS), February 1938 - Upper Mississippi River 9-Foot Channel, Lock & Dam No. 4, Alma, Buffalo County, WI

451

3. Down river view of lock and dam to southwest ...  

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

3. Down river view of lock and dam to southwest - Mississippi River 9-Foot Channel, Lock & Dam No. 1, In Mississippi River at Mississippi Boulevard, below Ford Parkway Bridge, Saint Paul, Ramsey County, MN

452

11. AVALON DAM GATE KEEPER'S COMPLEX: PUMPHOUSE AND LIFT ...  

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

11. AVALON DAM - GATE KEEPER'S COMPLEX: PUMPHOUSE AND LIFT FOR HOUSE WATER SUPPLY. VIEW TO EAST - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

453

15. DETAIL FROM NORTH END OF DAM, SHOWING TOP OF ...  

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

15. DETAIL FROM NORTH END OF DAM, SHOWING TOP OF NORTHERNMOST BUTTRESS, END OF CONCRETE WALK ATOP NORTH EMBANKMENT, AND THE ROCK CREEK RESERVOIR BEYOND. - Rock Creek Dam, East end of Rock Creek Road, Auburn, Placer County, CA

454

GENERAL AERIAL VIEW TO SOUTH OF ELWHA DAM AND POWERHOUSE ...  

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

GENERAL AERIAL VIEW TO SOUTH OF ELWHA DAM AND POWERHOUSE WITH NORTH END OF RESERVOIR. PHOTO BY JET LOWE, HAER, 1995. - Elwha River Hydroelectric System, Elwha Hydroelectric Dam & Plant, Port Angeles, Clallam County, WA

455

GENERAL AERIAL VIEW OF LAKE ALDWELL AND ELWHA DAM AND ...  

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

GENERAL AERIAL VIEW OF LAKE ALDWELL AND ELWHA DAM AND POWERHOUSE, WITH STRAIT OF JUAN DE FUCA TO THE NORTH. PHOTO BY JET LOWE, HAER, 1995. - Elwha River Hydroelectric System, Elwha Hydroelectric Dam & Plant, Port Angeles, Clallam County, WA

456

4. INTERIOR OF THE VALVE HOUSE, DIABLO DAM, SHOWING CONTROLS ...  

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

4. INTERIOR OF THE VALVE HOUSE, DIABLO DAM, SHOWING CONTROLS FOR RELIEF VALVE, 1989. - Skagit Power Development, Diablo Dam, On Skagit River, 6.9 miles upstream from Newhalem, Newhalem, Whatcom County, WA

457

Asymptotic formulae for correcting finite element predicted natural frequencies of gravity and embankment dams  

Microsoft Academic Search

Extraction of natural frequencies of a gravity dam or an embankment dam plays an important role in the seismic design of the dam because the seismic response of a dam is dependent largely on the dynamic characteristics of the dam. Owing to the lack of exact solutions and the geometry of a dam, numerical methods such as finite element methods

Chongbin Zhao; G. P. Steven

1996-01-01

458

The Conceptual Basis for Ecological Responses to Dam Removal  

Microsoft Academic Search

the removal of nonfunctioning dams or dams that cause environmental harm or present unsafe conditions (Poff et al. 1997, Hart and Poff 2002). The basis for assessment of the eco-logical responses to dam removal and for the design of eco-logically effective removal practices is largely conceptual. Par-ticularly in the Pacific Northwest, the adverse effects that large dams have on endangered

STAN GREGORY; HIRAM LI; JUDY LI

2002-01-01

459

2. View of the southern twothirds of the dam showing ...  

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

2. View of the southern two-thirds of the dam showing the Glens Falls Bridge over the Hudson River on the left, the Niagara Mohawk Power Corporation penstocks and inktake structure at the southeast corner of the dam, and the dam itself. The Finch Pruyn & Company Forebay is the foreground. Facing south. - Glens Falls Dam, 100' to 450' West of U.S. Route 9 Bridge Spanning Hudson River, Glens Falls, Warren County, NY

460

"No. 172. General view of the dam, looking downstream from ...  

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

"No. 172. General view of the dam, looking downstream from the east end. F.E.D. June, 1916." Compare this historic image, taken upon dam completion (1916), with current-condition photograph HAER CO-90-1. The dam retains a remarkable degree of integrity of design and setting - Grand Valley Diversion Dam, Half a mile north of intersection of I-70 & Colorado State Route 65, Cameo, Mesa County, CO

461

Out, Out, Dam Spot: The Geomorphic Response of Rivers to Dam Removal. Science Findings, Issue Seventy One, March 2005.  

National Technical Information Service (NTIS)

About 75,000 irrigation, flood control, and hydropower dams in the United States are aging, deteriorating, or have outlived their useful lives and purposes. Not surprisingly, dam removal is emerging as both a challenge and opportunity for river management...

2005-01-01

462

Jackson Mills and Mine Falls Dams, Nashua, New Hampshire. Reconnaissance Report, Hydroelectric Feasibility. Volume 1, Jackson Mills Dam.  

National Technical Information Service (NTIS)

This study investigated hydroelectric development at Jackson Mills Dam in Nashua New Hampshire. Reinstallation of hydroelectric power at Jackson Mills Dam has been determined feasible. During the 1950's the region switched from hydroelectric power to oil,...

1979-01-01

463

33 CFR 208.19 - Marshall Ford Dam and Reservoir (Mansfield Dam and Lake Travis), Colorado River, Tex.  

Code of Federal Regulations, 2013 CFR

...Mansfield Dam and Lake Travis), Colorado River, Tex. 208.19 Section...Mansfield Dam and Lake Travis), Colorado River, Tex. The Secretary of...through his agent, the Lower Colorado River Authority (LCRA)...

2013-07-01

464

33 CFR 208.19 - Marshall Ford Dam and Reservoir (Mansfield Dam and Lake Travis), Colorado River, Tex.  

Code of Federal Regulations, 2010 CFR

...Mansfield Dam and Lake Travis), Colorado River, Tex. 208.19 Section 208...Mansfield Dam and Lake Travis), Colorado River, Tex. The Secretary of the...through his agent, the Lower Colorado River Authority (LCRA) shall...

2010-07-01

465

33 CFR 100.1102 - Marine Events on the Colorado River, between Davis Dam (Bullhead City, Arizona) and Headgate Dam...  

Code of Federal Regulations, 2010 CFR

... false Marine Events on the Colorado River, between Davis Dam (Bullhead...1102 Marine Events on the Colorado River, between Davis Dam (Bullhead... Where: that portion of the Colorado River starting from the entrance...

2009-07-01

466

33 CFR 208.19 - Marshall Ford Dam and Reservoir (Mansfield Dam and Lake Travis), Colorado River, Tex.  

Code of Federal Regulations, 2010 CFR

...Mansfield Dam and Lake Travis), Colorado River, Tex. 208.19 Section 208...Mansfield Dam and Lake Travis), Colorado River, Tex. The Secretary of the...through his agent, the Lower Colorado River Authority (LCRA) shall...

2009-07-01

467

33 CFR 100.1102 - Marine Events on the Colorado River, between Davis Dam (Bullhead City, Arizona) and Headgate Dam...  

Code of Federal Regulations, 2010 CFR

... false Marine Events on the Colorado River, between Davis Dam (Bullhead...1102 Marine Events on the Colorado River, between Davis Dam (Bullhead... Where: that portion of the Colorado River starting from the entrance...

2010-07-01

468

Early Progress to Implement the Federal Guidelines for Dam Safety and Recommendations to Improve Federal Dam Safety Programs.  

National Technical Information Service (NTIS)

President Carter directed each of the Federal agencies responsible for dam safety to implement the new Federal Guidelines for Dam Safety on October 4, 1979. He also directed the major agency heads to report their progress toward implementing the Guideline...

B. A. Tschantz

1980-01-01

469

Effective dam removal and river channel restoration approaches  

Microsoft Academic Search

Millions of dams have been built on the planet's rivers and streams to provide societal needs for freshwater supplies, irrigation, hydroelectric development, industrial activities and flood control. The structural and operational components of most dams include features that reflect technological advancements and changing societal priorities over time. Many dams were constructed and operated with no consideration for river ecology; some

C. Katopodis; L. P. Aadland

2006-01-01

470

6. SOUTHERLYVIEW OF BIG TUJUNGA DAM SHOWING THE PARAPET WALL ...  

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

6. SOUTHERLYVIEW OF BIG TUJUNGA DAM SHOWING THE PARAPET WALL ALONG THE CREST, THE ELEVATOR SHAFT, AND THE CONTROL HOUSE AT THE END OF THE DAM. PHOTO TAKEN AT THE SOUTH OF THE SPILLWAY BRIDGE. - Big Tujunga Dam, 809 West Big Tujunga Road, Sunland, Los Angeles County, CA

471

1. VIEW OF DOWNSTREAM SIDE OF DIVERSION DAM ON THE ...  

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

1. VIEW OF DOWNSTREAM SIDE OF DIVERSION DAM ON THE SNAKE RIVER, LOOKING NORTHEAST. NOTE HEADGATE STRUCTURE ON NORTH BANK, SPILLWAY ON LEFT SIDE OF DAM, AND SPLASH LOGS ON DOWNSTREAM SIDE OF DAM. - Snake River Ditch, Headgate on north bank of Snake River, Dillon, Summit County, CO

472

30. Otter Lake Dam. View shows rustic stone facade of ...  

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

30. Otter Lake Dam. View shows rustic stone facade of the dam. The stepped face of the dam gives the illusion of a natural cascade. Facing southeast. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

473

Endodontics: Part 6 Rubber dam and access cavities  

Microsoft Academic Search

Rubber dam is easy to apply once the basic components and principles are understood. An efficient and well-trained dental nurse will greatly facilitate the application procedure. Although preparation of the access cavity may be commenced before rubber dam is applied to enable anatomical landmarks to be followed, the rubber dam should be placed as soon as possible with adequate protection

P Carrotte

2004-01-01

474

50. AVALON DAM Photographic copy of historic photo, c1889 ...  

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

50. AVALON DAM - Photographic copy of historic photo, c1889 (original print located at the Carlsbad Irrigation District offices, Carlsbad, New Mexico) photographer unknown 'ROCK CUT AND DAM AT HEAD OF DITCH ABOVE EDDY, N.M.' - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

475

52. AVALON DAM Photographic copy of historic photo, c1890 ...  

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

52. AVALON DAM - Photographic copy of historic photo, c1890 (original print located at the Carlsbad Irrigation District offices, Carlsbad, New Mexico) photographer unknown VIEW OF SCOURWAY THROUGH AVALON DAM DISCHARGING WATER - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

476

51. AVALON DAM Photographic copy of historic photo, c1889 ...  

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

51. AVALON DAM - Photographic copy of historic photo, c1889 (original print located at the Carlsbad Irrigation District offices, Carlsbad, New Mexico) photographer unknown VIEW OF EXCAVATION OF HEADGATE CHANNEL. ALSO SHOWS A PORTION OF DAM - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

477

61. AVALON DAM Photographic copy of historic photo, 1907 ...  

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

61. AVALON DAM - Photographic copy of historic photo, 1907 (original print located at the Carlsbad Irrigation District offices, Carlsbad, New Mexico) photographer unknown VIEW OF AVALON DAM RECONSTRUCTION - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

478

56. AVALON DAM Photographic copy of historic photo, December ...  

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

56. AVALON DAM - Photographic copy of historic photo, December 18, 1905 (original print located at the Carlsbad Irrigation District offices, Carlsbad, New Mexico) photographer unknown 'REMAINING PORTIONS OF WASHED OUT TEMPORARY DAM' - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

479

Debris dams and the relief of headwater streams  

Microsoft Academic Search

In forested, mountain landscapes where debris flows are common, their deposition commonly forms valley-spanning dams of wood, boulders, or complex mixtures of both in headwater valleys. Sediment impoundment behind these dams causes alluviation in what would otherwise be bedrock channels. In this paper, the effects of debris dams on the evolution of headwater valley profiles over geologic time are examined.

Stephen T. Lancaster; Gordon E. Grant

2006-01-01

480

6. VIEW OF DAM 83, SHOWING OUTLET CHANNEL FLOWING INTO ...  

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

6. VIEW OF DAM 83, SHOWING OUTLET CHANNEL FLOWING INTO POND A WITH DIVERSION GATES LONG EAST (LEFT) SIDE OF OUTLET CHANNEL, LOOKING SOUTH FROM DOWNSTREAM FACE OF THE DAM - Upper Souris National Wildlife Refuge, Dam 83, Souris River Basin, Foxholm, Ward County, ND

481

6. VIEW SHOWING CREST OF DAM AND OUTLET GATE WHEEL, ...  

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

6. VIEW SHOWING CREST OF DAM AND OUTLET GATE WHEEL, STEM AND STEM GUIDE, LOOKING SOUTHEAST - High Mountain Dams in Upalco Unit, Milk Lake Dam, Ashley National Forest, 9.4 miles Northwest of Swift Creek Campground, Mountain Home, Duchesne County, UT

482

Making an automated monitoring system work at Tolt Dam  

Microsoft Academic Search

A major upgrade of the dam safety program at Tolt Dam in Seattle, Washington is described. The upgrade was prompted by the age (30 years) of the dam, the addition of a hydroelectric plant, and public concern. The program is based on an automated condition monitoring and advance warning system. The design, implementation, and operating experience of the system are

J. M. Marilley; B. K. Myers

1996-01-01

483

Simple empirical model of aeration at navigation dams.  

National Technical Information Service (NTIS)

In a study of aeration at 28 dams in the upper Ohio River basin, a least-squares linear regression model was developed to predict the dissolved oxygen deficit below the dam as a linear function of the deficit above the dam. A linear statistical model was ...

S. F. Railsback

1990-01-01

484

20. VIEW FROM DOWNSTREAM SIDE OF DAM SHOWING BUTTS OF ...  

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

20. VIEW FROM DOWNSTREAM SIDE OF DAM SHOWING BUTTS OF LOGS PROJECTING BETWEEN CROSS LOGS. FREQUENTLY WHOLE TREES WERE USED IN CONSTRUCTING THESE DAMS. THE BRANCHES WERE PLACED UPSTREAM AND COVERED WITH EARTH AND STONE TO ANCHOR THEM. Photographed November 6, 1935. - Forge Creek Dam-John Cable Mill, Townsend, Blount County, TN

485

77 FR 50493 - Sam Rayburn Dam Project Power Rate  

Federal Register 2010, 2011, 2012, 2013

...Southwestern Power Administration Sam Rayburn Dam Project Power Rate AGENCY: Southwestern...SUMMARY: The current Sam Rayburn Dam Project rate was approved by the Federal...with the Sam Rayburn and Robert D. Willis Dams, two Corps projects that are isolated...

2012-08-21

486

43 CFR 418.18 - Diversions at Derby Dam.  

Code of Federal Regulations, 2012 CFR

...2011-10-01 true Diversions at Derby Dam. 418.18 Section 418.18 Public Lands...Management § 418.18 Diversions at Derby Dam. (a) Diversions of Truckee River water at Derby Dam must be managed to maintain minimum...

2012-10-01

487

25 CFR 173.16 - Reserved area, Coolidge Dam.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Reserved area, Coolidge Dam. 173.16 Section 173.16 Indians... § 173.16 Reserved area, Coolidge Dam. No permit for any commercial business...of a mile from the center of the Coolidge Dam,...

2011-04-01

488

Three gorges : the biggest dam in the world  

NSDL National Science Digital Library

Students will understand the following:The enormous Three Gorges Dam is now being constructed in China on the upper Yangtze River.The dam will benefit many people, but it may also cause serious problems.Dams are built according to complex principles of engineering.

Leaf, Jeffrey

2006-01-01

489

43 CFR 418.18 - Diversions at Derby Dam.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Diversions at Derby Dam. 418.18 Section 418.18 Public Lands...Management § 418.18 Diversions at Derby Dam. (a) Diversions of Truckee River water at Derby Dam must be managed to maintain minimum...

2011-10-01

490

75 FR 34476 - Glen Canyon Dam Adaptive Management Work Group  

Federal Register 2010, 2011, 2012, 2013

...INTERIOR Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY...renewing the charter for the Glen Canyon Dam Adaptive Management Work Group. The purpose...respect to the operation of Glen Canyon Dam and the exercise of other authorities...

2010-06-17

491

75. AVALON DAM Photographic copy of historic photo, April ...  

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

75. AVALON DAM - Photographic copy of historic photo, April 10, 1938 (original print in '1938 Annual Report of the Carlsbad Project,' located at the Carlsbad Irrigation District offices, Carlsbad, New Mexico) photographer unknown 'AVALON DAM - CCC ROCK WORK AT SPILLWAY NO. 2' - Carlsbad Irrigation District, Avalon Dam, On Pecos River, 4 miles North of Carlsbad, Carlsbad, Eddy County, NM

492

Experiments of Debris Flow Damming in Southeast Tibet  

Microsoft Academic Search

In this paper, the formations of jammed dam by debris flow's injection and the influences on mainstream's riverbed by subsequent outburst of the dam are discussed based on a model test. The experiments lasted 3 months, together with 13 groups of tests in all. As the junctional angle is equal to 90, the critical index of jammed dam was established

Zunlan CHENG; Chao Dang; Jingjing LIU; Yiwen GONG

2007-01-01

493

DESCHUTES PROJECT, OREGON, WICKIUP DAM, LOOKING NORTH FROM RIGHT ABUTMENT. ...  

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

DESCHUTES PROJECT, OREGON, WICKIUP DAM, LOOKING NORTH FROM RIGHT ABUTMENT. BUREAU MAINTENANCE BUILDINGS LOCATED BELOW THE DAM WITH ROUND MOUNTAIN BEYOND. SHOW COVERED CULTUS MOUNTAIN TO THE LEFT. Photocopy of historic photographs (original photograph on file at National Archives, Rocky Mountain Region, Denver, CO). R.A. Baker, Photographer, April 25, 1950 - Wickiup Dam, Deschutes River, La Pine, Deschutes County, OR

494

1. AERIAL VIEW OF LOCK AND DAM, LOOKING EAST Photocopy ...  

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

1. AERIAL VIEW OF LOCK AND DAM, LOOKING EAST Photocopy of photograph, ca. 1980, courtesy of the U.S. Engineer Office, St. Louis, Missouri. Original print on file at Mississippi River Lock and Dam No. 24, Clarksville, Missouri - Upper Mississippi River Nine-Foot Channel Project, Lock & Dam No. 24, Clarksville, Pike County, MO

495

Geomorphology and American dams: The scientific, social, and economic context  

Microsoft Academic Search

American geomorphologic research related to dams is embedded in a complicated context of science, policy, economics, and culture. Research into the downstream effects of large dams has progressed to the point of theory-building, but generalization and theory-building are from this research because (1) it is highly focused on a few locations, (2) it concerns mostly very large dams rather than

William L. Graf

2005-01-01

496

Mortalities of Downstream Migrant Salmon at McNary Dam  

Microsoft Academic Search

A 3-year study was conducted to determine mortality rates for downstream migrant salmonids passing through spillways or turbines at McNary Dam. Mortalities were determined by releasing marked fish into the exit under study (spillway or turbine) and marked control groups immediately below the dam. Samples of released fish were recovered at stations below the dam, and survival rates were computed

Dale E. Schoeneman; Richard T. Pressey; Charles O. Junge Jr

1961-01-01

497

RADEMACHER CHAOS: TAIL ESTIMATES VS LIMIT THEOREMS  

Microsoft Academic Search

We study Rademacher chaos indexed by a sparse set which has a fractional combinatorial dimension. We obtain tail estimates for finite sums and a normal limit theorem as the size tends to infinity. The tails for finite sums may be much larger that the tails of the limit.

RON BLEI; SVANTE JANSON

2003-01-01

498

Anaplasma phagocytophilum in White-tailed Deer  

Microsoft Academic Search

We examined the reservoir potential of white-tailed deer for Anaplasma phagocytophilum. Results suggest that white-tailed deer harbor a variant strain not associated with human infection, but contrary to published reports, white- tailed deer are not a reservoir for strains that cause human disease. These results will affect surveillance studies of vector and reservoir populations.

Robert F. Massung; Joshua W. Courtney; Shannon L. Hiratzka; Virginia E. Pitzer; Gary Smith; Richard L. Dryden

499

The evolution of gravel bed channels after dam removal: Case study of the Anaconda and Union City Dam removals  

Microsoft Academic Search

The Anaconda and Union City Dams on the Naugatuck River in Connecticut were removed in February and October 1999. A detailed study of the sites prior to removal was undertaken including sediment testing and predictions of upstream channel formation post-dam removal. The 3.35-m-high timber crib\\/rock fill spillway of the Anaconda Dam partially breached during a storm prior to the dam's

Laura A. S. Wildman; James G. MacBroom

2005-01-01

500

Nonlinear seismic response analysis of arch dam-foundation systems- part I dam-foundation rock interaction  

Microsoft Academic Search

The arch dam–foundation rock dynamic interaction and the nonlinear opening and closing effects of contact joints on arch dam\\u000a are important to the seismic response analysis of arch dams. Up to date, there is not yet a reasonable and rigorous procedure\\u000a including the two factors in seismic response analysis. The methods for the analysis of arch dam–foundation rock dynamic interaction

Xiuli Du; Yanhong Zhang; Boyan Zhang

2007-01-01