As a regulatory requirement of Entergy’s Clean Water Act permit (NPDES permit), Entergy must publish monthly reports for pollutants discharged into Cape Cod Bay by Pilgrim Nuclear Power Station. Entergy must collect wastewater samples, conduct tests of the samples, and report the results to the U.S. Environmental Protection Agency (EPA) in these monthly Discharge Monitoring Reports (DMR).
Here is a summary of Entergy’s latest DMR for Pilgrim (July 2015).
On July 18th and 19th, Pilgrim discharged approximately 10,600 gallons of process water into Cape Cod Bay in order to allow for annual maintenance of the system. The flow of this process water to Cape Cod Bay was on average about 7 gallons/minute, with a maximum flow of no more than 20 gallons/minute. In addition to pH and total suspended solids, the waste water also included boron (often used in nuclear plants to control speed of nuclear fission), sodium nitrite (a corrosion inhibitor and additive to industrial greases) and tolyltriazole (a corrosion inhibitor). While Entergy reports that these substances are below permit requirements, the idea that “dilution is the solution to pollution” is a mistaken old rule. Today, we know that many pollutants (including industrial chemicals) can be harmful to people and wildlife even in small amounts.
Entergy also reports in its July DMR that Pilgrim used on average 446.4 million gallons of water per day from Cape Cod Bay in its once-through cooling system. Pilgrim’s heated water (aka, thermal pollution) that was discharged into the Bay in July was about 96°F (Pilgrim’s permitted limit is 102°F) – making it about 31°F hotter than the ambient temperature of the Bay (Pilgrim’s permitted limit is 32°F).
Table from page 5 of Entergy’s July 2015 DMR for Pilgrim, showing results from Pilgrim’s condenser cooling water.
Pilgrim’s Clean Water Act permit that regulates these discharges is 19 years expired. EPA and Mass. Department of Environmental Protection – the agencies in charge of Pilgrim’s permit – need to terminate the permit entirely and stop the pollution of Cape Cod Bay. Learn more about Pilgrim’s expired permit →