783 resultados para Discharges


Relevância:

20.00% 20.00%

Publicador:

Resumo:

At head of title: Office of Naval Research. Contract N6 onr 243. Task order IV. Technical report no. 2.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

"Prepared in cooperation with the Texas Highway Department and the U.S. Department of Transportation, Federal Highway Administration."

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Office of Naval Research. Contract N6 onr-243. Task order IV. Technical report no. 3.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Office of Naval Research. Contract ONR 243. Task order V. Technical report no. 1.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Mode of access: Internet.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

"Project no. 60.040."

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Bibliography: p. 38.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Mode of access: Internet.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Mode of access: Internet.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A broad based approach has been used to assess the impact of discharges to rivers from surface water sewers, with the primary objective of determining whether such discharges have a measurable impact on water quality. Three parameters, each reflecting the effects of intermittent pollution, were included in a field work programme of biological and chemical sampling and analysis which covered 47 sewer outfall sites. These parameters were the numbers and types of benthic macroinvertebrates upstream and downstream of the outfalls, the concentrations of metals in sediments, and the concentrations of metals in algae upstream and downstream of the outfalls. Information on the sewered catchments was collected from Local Authorities and by observation of the time of sampling, and includes catchment areas, land uses, evidence of connection to the foul system, and receiving water quality classification. The methods used for site selection, sampling, laboratory analysis and data analysis are fully described, and the survey results presented. Statistical and graphical analysis of the biological data, with the aid of BMWP scores, showed that there was a small but persistent fall in water quality downstream of the studied outfalls. Further analysis including the catchment information indicated that initial water quality, sewered catchment size, receiving stream size, and catchment land use were important factors in determining the impact. Finally, the survey results were used to produce guidelines for the estimation of surface water sewer discharge impacts from knowledge of the catchment characteristics, so that planning authorities can consider water quality when new drainage systems are designed.

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Resumo:

DUE TO COPYRIGHT RESTRICTIONS ONLY AVAILABLE FOR CONSULTATION AT ASTON UNIVERSITY LIBRARY AND INFORMATION SERVICES WITH PRIOR ARRANGEMENT