Endocrine Disrupters in Receiving Waters

Abstract Data are provided on the release of 5 radionuclides, 17 metals and 7 major ions from a uranium mining operation in northern Saskatchewan. The downstream concentration of these contaminants is documented, and the point of “no discernible impact” is determined. Sediments in a downstream lake are monitored for uranium and molybdenum, and the post-release fate of these metals is discussed.

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Problems in Detoxifying Fresh Waters Polluted by Base Metal Minewaters

Water Quality Research Journal ◽

10.2166/wqrj.1971.005 ◽

1971 ◽

Vol 6 (1) ◽

pp. 53-79

Author(s):

Vaclav Kresta ◽

Gerald B. Ward

Keyword(s):

Chelating Agents ◽

Toxicity Tests ◽

Contaminated Water ◽

Total Dosage ◽

Toxic Compounds ◽

Mining Sites ◽

Know How ◽

Chemical Agents ◽

Copper And Zinc ◽

Receiving Waters

Abstract At many mining sites process (milling) and drainage waters escape treatment and cause receiving waters to become contaminated above avoidance or even toxic levels for fish. The present know-how on chemical agents which can be used to complex with copper and zinc to form non-toxic compounds is limited to chelating agents such as NTA or EDTA. Preferential reaction with trivalent ions such as iron means that such ions must be tied up before complexation of copper and zinc can occur. As the amount of iron in contaminated water is usually two to eight times higher than that of copper and zinc, high dosages of chelating agents are usually required. In this project, the use of salts of anthranilic acid, especially calcium anthranilate, was investigated. The consumption of anthranilateions was found to be about the same as that of NTA or EDTA, i.e. four milligrams per milligram of copper or zinc. The total dosage to be applied to contaminated waters would be, however, several times lower as iron is not involved in the reactions and copper and zinc are complexed in that order. Toxicity tests to compare the efficiency and dasages of calcium anthranilate and NTA or EDTA are presently being carried out.

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Effect of Salinity on Reaeration Coefficient of Receiving Waters

Water Science & Technology ◽

10.2166/wst.1984.0127 ◽

1984 ◽

Vol 16 (5-7) ◽

pp. 139-154 ◽

Cited By ~ 1

Author(s):

Ching-Gung Wen ◽

Jao-Fuan Kao ◽

Lawrence K Wang ◽

Chii Cherng Liaw

Keyword(s):

Saline Water ◽

Chloride Concentration ◽

Practical Method ◽

Tidal River ◽

Quality Analysis ◽

Flow Conditions ◽

Water Quality Analysis ◽

Design Engineers ◽

Reaeration Coefficient ◽

Receiving Waters

A practical method of determining reaeration coefficients would greatly aid design engineers in determining the degree of wastewater treatment required for a proposed effluent discharge. Many previous tidal river and estuary studies emphasized mainly the effects of flow conditions (such as velocity, water depth, turbulent intensity, hydraulic gradient, etc.) and temperature on stream aeration, and the effect of salts was not seriously considered. In this research a new mathematical model of reaeration coefficient considering the effect of salts has been developed for water quality analysis in tidal rivers and estuaries. The reaeration coefficient in saline water, k2s(day−1, base e) at any chloride concentration C(g/l) and at 20°C, can be expressed byin which k2f is the reaeration coefficient in fresh water at 20°C. The correlation coefficient of k2s/k2f and C is 0.88.

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Use of Biomonitoring to Control Toxics in the United States

Water Science & Technology ◽

10.2166/wst.1988.0129 ◽

1988 ◽

Vol 20 (10) ◽

pp. 101-108 ◽

Cited By ~ 6

Author(s):

Nelson A. Thomas

Keyword(s):

Water Quality ◽

Chronic Toxicity ◽

National Policy ◽

Single Species ◽

Field Studies ◽

The United States ◽

Toxicity Tests ◽

Toxic Pollutants ◽

Receiving Waters ◽

Biological Field

A biomonitoring program has been developed in support of the National Policy for the Development of Water Quality-Based Permit Limitations for Toxic Pollutants. The program focuses on the use of laboratory toxicity tests on aquatic plants and animals to predict ecosystem impact caused by toxic pollutants. Both acute and chronic toxicity tests were developed to test effluents and ambient waters. Laboratory and biological field studies were conducted at nine sites. Single species laboratory toxicity tests were found to be good predictors of impacts on the ecosystem when two or more species were used. Biomonitoring can be undertaken either on effluents and/or on the receiving waters. In that toxicity related to seeps, leachates and storm sewers has often been found upstream from dischargers, it is beneficial to conduct both effluent and ambient biomonitoring.

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Sprat – A Simple River Quality Impact Model for Intermittent Discharges

Water Science & Technology ◽

10.2166/wst.1989.0171 ◽

1989 ◽

Vol 21 (12) ◽

pp. 1793-1796

Author(s):

C. P. Crockett ◽

R. W. Crabtree ◽

H. R. Markland

Keyword(s):

Plug Flow ◽

River System ◽

Response Assessment ◽

River Basin Management ◽

Impact Model ◽

Basin Management ◽

Potential Accuracy ◽

North West ◽

River Quality ◽

Receiving Waters

The detrimental influence of storm sewer overflows on urban river quality has been widely recognised for many years. One objective of the WRc River Basin Management programme is the development of a river impact model capable of predicting the transient quality changes in receiving waters due to intermittent storm sewage discharges. The production of SPRAT (Spill Pollution Response Assessment Technique) is the first step in the development of such a model. SPRAT incorporates a number of significant simplifications, most notably plug flow and instantaneous mixing, and does not implicitly take into account the effects of dispersion. These simplifications reflect the large errors associated with the model inputs. These errors severely limit the potential accuracy of any river impact model. The model has been applied to the Bolton river system in North West England. The development and application of SPRAT has enabled the requirements for a more sophisticated river quality impact model to be clearly defined, in addition to highlighting the problems associated with gathering suitable data with which to build and calibrate such a model.

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Methods for Calculation of Annual and Extreme Overflow Events from Combined Sewer Systems

Water Science & Technology ◽

10.2166/wst.1984.0200 ◽

1984 ◽

Vol 16 (8-9) ◽

pp. 311-325 ◽

Cited By ~ 5

Author(s):

N B Johansen ◽

P Harremoës ◽

M Jensen

Keyword(s):

Extreme Event ◽

Short Term ◽

Sewer Systems ◽

Extreme Load ◽

Combined Sewer ◽

Receiving Waters ◽

Water Problems ◽

Source Of Pollution ◽

Receiving Water

Overflow from combined systems constitute an increasing source of pollution of receiving waters, as compared to daily wastewater discharges which undergo treatment to a still higher extent. The receiving water problems from overflows are significant both in a long term scale (mean annual load) and in a short term scale (extreme event load). A method for computation of both annual and extreme load is presented. It is based on historical rain series and the use of a time-area model and simple pollutant mixing model in runoff calculation. Statistical calculations for both mean annual load and extreme events have been applied to the computed overflow series. Based on the computerized method simple manual calculations methods have been developed, resulting in graphs and tables for annual load and extreme load.

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