The new Section 316(b) Phase II/III rule could require all existing facilities with cooling water intakes and once-through cooling to install cooling towers and convert to closed-cycle cooling. In many cases, this upgrade cost could exceed the benefits.
Q: Could the new Section 316(b) Phase II/III rule require all existing facilities with cooling water intakes and once-through cooling to install cooling towers and convert to closed-cycle cooling?
A: Under the proposed rule, all existing facilities using a cooling water intake with a designed intake rate greater than 2 million gallons per day must meet standards for impingement and entrainment mortality based on the best technology available (BTA). The entrainment standard is the most concerning because the BTA has been defined as reducing intake rate to that commensurate with closed-cycle cooling based on full-wet cooling towers.
Based on the Supreme Court ruling in Entergy Corp v. Riverkeeper Inc. et al. (April 1, 2009), which allowed the U.S. Environmental Protection Agency to consider costs and benefits when making BTA determinations, the proposed Section 316(b) rule leaves to each state the determination of BTA for entrainment on a case-by-case basis. The rule prescribes the factors the states must consider in the determination and prescribes studies the facility owners must conduct to provide the states with the needed information.
Combined, these studies amount to a cost-benefit analysis. In many cases, the cost of converting to closed-cycle cooling is expected to greatly exceed the benefits to the aquatic resources, and retrofitting cooling towers will not be required.
Greg Howick is the senior aquatic ecologist at Burns & McDonnell.