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Unified Agenda 2040-AE95

Criteria and Standards for Cooling Water Intake Structures


Section 316(b) of the Clean Water Act (CWA) requires EPA to ensure that the location, design, construction, and capacity of cooling water intake structures reflect the best technology available (BTA) for minimizing adverse environmental impacts. Under a consent decree with environmental organizations, EPA divided the section 316(b) rulemaking into three phases. All new facilities except offshore oil and gas exploration facilities were addressed in Phase I in December 2001; in July 2004, EPA promulgated Phase II, which covered large existing electric generating plant; and all new offshore oil and gas exploration facilities were later addressed in June 2006 as part of Phase III. In July 2007, EPA suspended the Phase II rule following the Second Circuit decision. Several parties petitioned the U.S. Supreme Court to review that decision, and the Supreme Court granted the petitions, limited to the issue of whether the Clean Water Act authorized EPA to consider the relationship of costs and benefits in establishing section 316(b) standards. On April 1, 2009, the Supreme Court reversed and remanded the case to the Second Circuit. The Second Circuit subsequently granted a request from EPA that the case be returned to the Agency for further consideration. In June 2006, EPA promulgated the Phase III regulation, covering existing electric generating plants using less than 50 MGD of cooling water, new offshore oil and gas facilities, and all existing manufacturing facilities. Petitions to review this rule were filed in the U.S. Court of Appeals for the Fifth Circuit. In July 2010, the U. S. Court of Appeals for the Fifth Circuit issued a decision upholding EPA's rule for new offshore oil and gas extraction facilities. Further, the court granted the request of EPA and environmental petitioners in the case to remand the existing facility portion of the rule back to the Agency for further rulemaking. EPA entered into a settlement agreement with the plaintiffs in two lawsuits related to section 316(b) rulemakings. Under the settlement agreement, as twice modified, EPA agreed to sign a notice of a proposed rulemaking implementing section 316(b) of the CWA at existing facilities no later than March 28, 2011, and to sign a notice taking final action on the proposed rule no later than June 27, 2013. Plaintiffs agreed to seek dismissal of both their suits, subject to a request to reopen one of the lawsuits in the event EPA failed to meet the agreed deadlines. EPA's proposed regulation includes uniform controls at all existing facilities to prevent fish from being trapped against screens (impingement), site-specific controls for existing facilities other than new units to prevent fish from being drawn through cooling systems (entrainment), and uniform controls equivalent to closed cycle cooling for new units at existing facilities (also entrainment). Other regulatory options analyzed included similar uniform impingement controls, and progressively more stringent requirements for entrainment controls. Another option considered would imposed the uniform impingement controls only for facilities withdrawing 50 million or more gallons per day of cooling water, with site-specific impingement controls for facilities withdrawing less than 50 million gallons per day. EPA issued two notices of data availability (NODA) in June 2012 that described flexibilities EPA is considering as part of the impingement mortality limitations and that described the preliminary results of surveys of households' willingness to pay for incremental reductions in fish mortality.


5 actions from April 20th, 2011 to July 2013


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