Discharge limits for specific facilities depend on local, State and Federal water restrictions as permitted under the National Pollutant Discharge Elimination System program.
For power plants greater than 25 MW, the U.S. Environmental Protection Agency effluent limitation guideline for chlorine is 0.2 mg L-1 (ppm) TRC (Federal Register, 40 CFR Part 423, November 1982). This discharge concentration is limited to 2 hr per day unless the need for use in combating macrofouling is demonstrated (Jenner and Janssen-Mommen 1993).
Other discharge configurations may be permitted. For example, the Perry Nuclear Power Plant, North Perry, Ohio, has a regulatory discharge limit for chlorine of maximum daily discharge time of 2 hr, with concentration limits of 0.2 mg L-1 for a 30-day average and 0.5 mg L-1 on a daily basis (Barton 1993).
Zebra Mussel Chemical Control Guide
Hypochlorite and Chlorine Gas