Mirant Kendall Station Fact Sheet

Mirant Kendall Station (MKS) is located just downstream of the Longfellow Bridge in the lower Charles River Basin. The area is bordered by the Esplanade and Department of Conservation and Recreation parkland, houses the Community Boating facility and the BU and MIT boathouses, and is used by rowers, kayakers, sailors, power boaters, windsurfers and recreational anglers. To date, millions of dollars have been spent by the cities of Cambridge and Boston to clean up the Charles.

To cool its turbines, MKS draws water from a canal connected to the Charles River, uses the water to absorb heat, and then dumps the heated water back into the river. This is called "once-through" cooling.

EPA and DEP have issued a joint draft permit under the Clean Water Act which would permit MKS to discharge heated water into the Charles River at excessive levels. This discharge would effectively render 50% of the area of the river between the Museum of Science and Community Boating (approximately 60 acres of surface area) a dead zone for certain life stages of some indigenous fish populations, would adversely affect aquatic life, and may exacerbate existing problems with excessive nutrients, oxygen depletion and water clarity.

The cooling water intake will on average amount to 70 million gallons per day at temperatures up to 105 degrees F., and up to 20 degrees higher than ambient temperatures. Excessive heat has been documented to adversely affect fish populations. Also, increases in water temperature, combined with nutrients can cause high production of algae (including noxious blue-green algae) potentially leading to or worsening algal blooms. The permit allows for increases in heat load to the Charles that would be approximately 414% to 545% greater than historic heat load levels.

During periods of low water flow in the Charles, the flow of river water passing through and being heated by the plant may be five times greater than the natural flow of the Charles.

The permit sets thermal limits that allow 50% of the cross-sectional area of the Charles River Basin (approximately 60 acres of surface area) to exceed those deemed necessary to protect aquatic organisms. The thermal limits set in the other half of the area more closely resemble maximum tolerance levels than the thermal levels found to be the most beneficial to aquatic species. Even though there are many other stressors besides heat affecting the aquatic community in the Charles, the EPA did not consider the impact of these additional stressors nor provide adequate margin of safety to ensure the protection of aquatic life (as required to do by the Clean Water Act).

MKS's cooling system kills millions of organisms per year because of impingement and entrainment. Small organisms, fish eggs and larvae are carried into the facility and die because of exposure to extreme heat, chemical pollution and turbulence. Larger fish do not fare better - they are impinged against the intake filters, where they are crushed or drown. The draft permit does little to address this problem.

PUBLIC COMMENTS:

We encourage the public to submit comments to the EPA.  Written comments on the Draft Permit may be submitted until Septembr 30, 2004 to:

George Papadopoulos, U.S. EPA
1 Congress Street - Suite 1100
Mailcode CPE
Boston, MA 02114-2023

Telephone: (617) 918-1579

The public comment period will close September 30, 2004.  Following the close of the comment period, the Regional Administrator of the EPA will issue a copy of the Final Permit decision to the applicant, Mirant Kendall, L.L.C., and each person who has submitted written comments of requested notice.

Information compiled by CRWA, Conservation Law Foundation and Clean Water Action.