Protection aquatic life

Where acid drainage is well developed and extensive, the costs of remediation can be high. In the Summitville, Colorado district (USA), for example, efforts to limit the contamination of fertile irrigated farmlands in the nearby San Luis Valley and protect aquatic life in the Alamosa River will cost an estimated 100 million or more (Plumlee, 1994a). 

Nagpal, N.K. 1994. Development of water quality and sediment criteria for PAHs to protect aquatic life. Pages 193-198 in D.D. Mackinley (ed.). High Performance Fish Proceedings of an International Fish Physiology Symposium. University of British Columbia in Vancouver, Canada, July 16-21, 1994. 

Acute water quality criteria for protecting aquatic life 22 pg/L (free cyanide) ... 

Even though water is affected by temperature and pressure, such effects are minimized until the boiling or freezing point is reached. Furthermore, some of these effects are not as obvious as one might expect. For example, water reaches a minimum volume at 4°C, and below 4°C its volume starts to increase again, explaining the potential of ice to float in water, helping to protect aquatic life. 

States have made substantial recent progress in the adoption, and EPA approval, of toxic pollutant water quality standards. Furthermore, virtually all states have at least proposed new toxics criteria for priority toxic pollutants since Section 303(c)(2)(B) was added to the CWA in February 1987. Unfortunately, not all such state proposals address, in a comprehensive manner, the requirements of Section 303(c)(2)(B). For example, some states have proposed to adopt criteria to protect aquatic life, but not human health other states have proposed human health criteria that do not address major exposure pathways (such as the combination of both fish consumption and drinking water). In addition, in some cases final adoption of proposed state toxics criteria that would be approved by EPA nas been substantially delayed due to controversial and difficult issues associated with the toxic pollutant criteria adoption process. 

To ensure technically sound decision making, EPA should review its water quality criteria at a minimum of every 10 years. EPA s water quality criteria consist of information regarding the concentrations of chemicals or levels of parameters in water that protect aquatic life and human health, and act as regulatory thresholds for determination of impaired waters. Many of EPA s current water quality criteria are outdated, and have not been developed using consistent methodologies. 

If predicted exposure is higher than toxicity (including the relevant imcertainty factor) for the most sensitive species and endpoint, an unacceptable risk is expected but a refinement of the assessment is possible (famous unless clauses of Annex VI). Another frequently used option is to set risk mitigation measures like buffer zones to protect aquatic life but also arthropods and plants. 

No regulations governing PCDD contamination exist at present to protect sensitive species of wildlife and aquatic organisms. Data available suggest that 2,3,7,8-TCDD concentrations in water should not exceed 0.01 ppt to protect aquatic life, or 10.0 to... 

In certain instances it may be necessary for the product to have a buffer zone restriction added to the label to protect aquatic life. 

This mitigates against the simplistic application of a single standard to protect aquatic life in all waters. At the same time, it complicates the derivation, application and adminstration of standards individually designed to suit a particular water. 

Ambient water quality maximum concentration of lead in drinking water has typically been 50 pg/L, but in the USA has been changed to an action limit of 15 pg/L. Standards to protect aquatic life are given as 65 pg/L for freshwater systems and 210 pg/L for saltwater systems. 

The national recommended water quality criteria for lead (65 FR 31682) derived by the U.S. EPA [per 304(a)(l)], as with all the pollutant criteria, included freshwater and saltwater acute and chronic criterion concentrations to protect aquatic life. The corresponding values (pgPb/l) are 65, 2.5, 210, and 8.1, respectively. As of June 1, 2010, there were no human health criteria for lead in terms of fish consumption or fish plus water consumption, previous values having been withdrawn (Table 28.2). 

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