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U.S. House Version of WRDA Does Not Include WIFIA

North Dakota and Wyoming Congressional Delegations Push for State Control of Hydraulic Fracturing Regulations



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USEPA Releases Updated Water Quality Criteria for Ammonia in Freshwater

USEPAThe United States Environmental Protection Agency (USEPA) has released its final national ambient water quality criteria recommendations for ammonia in freshwater as an update to the 1999 Clean Water Act. Ammonia is a constituent of nitrogen pollution. At high levels, it can lead to a toxic buildup in acquatic organisms' internal tissues and blood, and potentially cause death. Environmental factors, such as water pH and temperature, can affect ammonia toxicity in aquatic animals. The updated criteria reflects new data on sensitive freshwater mussels and snails, and incorporates the responses received on USEPA's draft 2009 criteria.

2013 USEPA Recommended Water Quality Criteria for Ammonia:

  • Acute Magnitude: 17 mg Total Ammonia Nitrogen (TAN) per liter (L) at pH 7 and 20°C for a one-hour average duration, not to be exceeded more than once every three years on average.
  • Chronic Magnitude: 1.9 mg TAN/L at pH 7 and 20°C for a 30-day average duration, not to be exceeded more than once every three years on average. The highest four-day average within a 30-day period should not exceed 2.5 times the chronic criterion magnitude more than once in three years on average.

Supporting documents have been published by the USEPA to assist States, territories, and authorized tribes that are considering adopting the newly recommended criteria and establishing water quality standards. There are flexibilities for applying the recommendations that States may consider, including the Recalculation Procedure for site-specific criteria derivation, variances, revisions to designated uses, dilution allowances, and compliance schedules. For more information about the options, click here.

To read the USEPA's entire white paper about its recommendations for ammonia levels in freshwater, click here.




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