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Approaches to verification of two-dimensional water quality models (open access)

Approaches to verification of two-dimensional water quality models

The verification of a water quality model is the one procedure most needed by decision making evaluating a model predictions, but is often not adequate or done at all. The results of a properly conducted verification provide the decision makers with an estimate of the uncertainty associated with model predictions. Several statistical tests are available for quantifying of the performance of a model. Six methods of verification were evaluated using an application of the BETTER two-dimensional water quality model for Chickamauga reservoir. Model predictions for ten state variables were compared to observed conditions from 1989. Spatial distributions of the verification measures showed the model predictions were generally adequate, except at a few specific locations in the reservoir. The most useful statistics were the mean standard error of the residuals. Quantifiable measures of model performance should be calculated during calibration and verification of future applications of the BETTER model. 25 refs., 5 figs., 7 tabs.
Date: November 1, 1990
Creator: Butkus, S.R. (Tennessee Valley Authority, Chattanooga, TN (USA). Water Quality Dept.)
System: The UNT Digital Library
Water quality investigation of Kingston Fossil Plant dry ash stacking (open access)

Water quality investigation of Kingston Fossil Plant dry ash stacking

Changing to a dry ash disposal systems at Kingston Fossil Plant (KFP) raises several water quality issues. The first is that removing the fly ash from the ash pond could alter the characteristics of the ash pond discharge to the river. The second concerns proper disposal of the runoff and possibly leachate from the dry ash stack. The third is that dry ash stacking might change the potential for groundwater contamination at the KFP. This report addresses each of these issues. The effects on the ash pond and its discharge are described first. The report is intended to provide reference material to TVA staff in preparation of environmental review documents for new ash disposal areas at Kingston. Although the investigation was directed toward analysis of dry stacking, considerations for other disposal options are also discussed. This report was reviewed in draft form under the title Assessment of Kingston Fossil Plant Dry Ash Stacking on the Ash Pond and Groundwater Quality.'' 11 refs., 3 figs., 18 tabs.
Date: April 1, 1990
Creator: Bohac, C.E.
System: The UNT Digital Library
PCB studies on fish from Watts Bar, Fort Loudoun, Tellico, and Melton Hill Reservoirs, 1988 (open access)

PCB studies on fish from Watts Bar, Fort Loudoun, Tellico, and Melton Hill Reservoirs, 1988

The Tennessee Valley Authority (TVA) reservoirs that are the subject of this report have been under investigation for several years due to contamination with polychlorinated biphenyls (PCBs). The study has two primary objectives: (1) define the geographical boundaries where contamination in fish ceases to be a problem and (2) determine the trend in PCB loading in fish from reservoirs where the contamination has been well defined. The purpose of this document is to briefly describe results of PCB analysis of fish collected from these reservoirs in autumn 1988 and compare them to results for previous years. These results were shared with all members on the study team as soon as they were received from the analytical laboratory rather than waiting for this formal report. Therefore, decisions on updating existing advisories and selection of study design for autumn 1989 were made months before this document was prepared. 6 refs., 21 tabs.
Date: September 1, 1990
Creator: Dycus, D. L.
System: The UNT Digital Library
Status of Norris Reservoir (open access)

Status of Norris Reservoir

This is one in a series of reports prepared by the Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overview of Norris Reservoir summarizes reservoir and watershed characteristics, reservoir uses, conditions that impair reservoir uses, water quality and aquatic biological conditions, and activities of reservoir management agencies. This information was extracted from the most up-to-date publications and data available, and from interviews with water resource professionals in various federal, state, and local agencies, and in public and private water supply and wastewater treatment facilities. 14 refs., 3 figs.
Date: September 1, 1990
Creator: unknown
System: The UNT Digital Library
South Fork Holston River basin 1988 biomonitoring (open access)

South Fork Holston River basin 1988 biomonitoring

There is concern over the effects of shifts in land use use practices on the aquatic fauna of streams in the South Fork Holston River basin in northwestern North Carolina and southwestern Virginia. Trout reproduction has noticeably declined in the Watauga River subbasin. The Watauga River and Elk River subbasins have been subjected to commercial and resort development. The Middle fork Holston River and the upper South Fork Holston River subbasins have been affected by agricultural and mining activities, respectively (Cox, 1986). To aid reclamation and management of the South Fork Holston basin, Tennessee Valley Authority (TVA) biologists conducted biomonitoring--including index of biotic integrity and macroinvertebrate sampling--on the Middle Fork Holston, South Fork Holston, Watauga, and Elk Rivers to assess cumulative impairment related to changes in habitat and pollutant loading in these subbasins. Biomonitoring can detect environmental degradation, help document problem areas, and assist in development of strategies for managing water quality. This report discusses the methods and materials and results of the biomonitoring of South Fork Holston River Basin. 13 refs., 5 figs., 12 tabs.
Date: June 1, 1990
Creator: Saylor, C. F. & Ahlstedt, S. A.
System: The UNT Digital Library
Texas Research League Annual Report: 1989 (open access)

Texas Research League Annual Report: 1989

Annual report of the Texas Research League describing goals, activities, and accomplishments during fiscal year 1989.
Date: 1990~
Creator: Texas Research League
System: The Portal to Texas History
Texas State Health Plan: 1991-92, Volume 1 (open access)

Texas State Health Plan: 1991-92, Volume 1

Biennial document outlining statewide health concerns and recommended strategies, including facilities and programs that will help assure equitable access for all Texas residents.
Date: 1990
Creator: Texas. Statewide Health Coordinating Council.
System: The Portal to Texas History
Texas Higher Education Coordinating Board Statistical Report: 1990 (open access)

Texas Higher Education Coordinating Board Statistical Report: 1990

Statistical report about various data collected on Texas state colleges and universities during fiscal year 1990 such as enrollment, faculty, credit hours, facilities, state appropriations, and student loans.
Date: 1990~
Creator: Texas Higher Education Coordinating Board
System: The Portal to Texas History
Archaeological survey of the 200 East and 200 West Areas, Hanford Site, Washington (open access)

Archaeological survey of the 200 East and 200 West Areas, Hanford Site, Washington

Responding to a heavy demand for cultural resource reviews of excavation sites, the Westinghouse Hanford Company contracted with Pacific Northwest Laboratory to conduct a comprehensive archaeological resource review for the 200 Areas of the Hanford Site, Washington. This was accomplished through literature and records review and an intensive pedestrian survey of all undisturbed portions of the 200 East Area and a stratified random sample of the 200 West Area. The survey, followed the Secretary of the Interior's guidelines for the identification of historic properties. The result of the survey is a model of cultural resource distributions that has been used to create cultural resource zones with differing degrees of sensitivity. 11 refs., 7 figs., 1 tab.
Date: March 1, 1990
Creator: Chatters, J. C. & Cadoret, N. A.
System: The UNT Digital Library
Texas State Board of Plumbing Examiners Annual Report: 1990 (open access)

Texas State Board of Plumbing Examiners Annual Report: 1990

Annual report of the Texas State Board of Plumbing Examiners describing goals, activities, and accomplishments during fiscal year 1990.
Date: 1990
Creator: Texas State Board of Plumbing Examiners
System: The Portal to Texas History
Geophysical Investigations of the Western Ohio-Indiana Region : Annual Report, October 1988-September 1989 (open access)

Geophysical Investigations of the Western Ohio-Indiana Region : Annual Report, October 1988-September 1989

A report regarding geophysical investigations of the Western Ohio-Indiana Region
Date: February 1990
Creator: Young, C. J.; Lay, T. & Jacobson, Willard J.
System: The UNT Digital Library
Texas Turfgrass Research: 1990 (open access)

Texas Turfgrass Research: 1990

Consolidated progress report providing a summary of research conducted at the experiment station during the prior year related to grass varieties used as turf, including growth and development, turfgrass cultivars, environment, pests, and culture.
Date: June 1990
Creator: Texas Agricultural Experiment Station
System: The Portal to Texas History