Decommissioning the Benning Road Power Plant

As of June 1, operations at the Benning Road Power Plant have ceased as announced by Pepco Energy Services (PES), a wholly owned subsidiary of Pepco Holdings, Inc., which has owned and operated the power plant since 2000. The power plant is located on the western most portion of the Benning Service Center site, where it occupies approximately 25 percent of the facility's 77 acres. Preparations for closing the power plant have been underway since 2007. As part of the closure, the plant and adjoining areas will be cleaned, secured, and maintained in accordance with District of Columbia and Federal environmental regulations.

What was the Benning Road Power Plant?
The power plant was built in 1906, and provided Pepco's first system-wide electricity supply to the District of Columbia and nearby Maryland suburbs. Over the years, the power plant operated and subsequently retired several different generating units, reflecting advances in technology and operating on different types of fuel. Two oil-fired steam turbine units, installed in 1968 and 1972, provided a combined 550 MW of electricity; enough to meet the needs of around 180,000 homes. Designed to operate a limited number of days each year, these units operated an average of 10 to 15 days annually to ensure reliable power to Pepco's customers during periods of peak electricity demand.

How will the Power Plant Decommissioning be implemented?
As of June 1, operations at the Benning Power Plant have ceased as scheduled and PES has placed the plant into an idle condition termed a "Cold Closure". The next steps are to clean and secure the plant and portions of the property as required by District of Columbia and Federal environmental regulations and good management practices. The power plant decommissioning proceeds during the course of the next several months.

What is "Cold Closure"?
Cold Closure is defined as a condition in which utility service to the Power Plant is disconnected, and no longer operable. Cold Closure is intended to require only essential maintenance until the plant is completely decommissioned. As a part of Cold Closure, all systems that are subject to failure due to freezing will be decommissioned, and materials used in power plant operations will be removed.

What happens during the Closure?
The first step for the closure of the Benning Power Plant is to shutdown the two steam turbine units, the auxiliary boilers, the preheat generator, and all related equipment. Next, weatherproof fire suppression equipment will be installed as required by the District of Columbia Fire Marshal. Then, the cooling tower structures will be drained, dismantled and removed.

PES will follow all environmental regulatory requirements established by the District of Columbia and federal agencies. These requirements fall into several categories including air pollution control, water pollution control, solid and hazardous waste management, above ground tanks, and several requirements pertaining to maintenance of buildings (e.g., polychlorinated biphenyls (PCBs), asbestos, lead-based paint, mold). Specific closure activities under each of these categories are discussed below.

Air Pollution Control Water Pollution Control Solid/Hazardous Waste Above Ground Tanks Buildings/Structures

Does the Power Plant Closure affect the Service Center?
No, the Power Plant occupies approximately 25 percent of the facility's 77 acres. The Service Center occupies the largest part of the property, and accommodates about 700 Pepco employees. Service Center employees work in maintenance and construction of Pepco's electric transmission and distribution system; system engineering; vehicle fleet maintenance and refueling; and central warehouses for all the materials, supplies and equipment needed to operate the Pepco electrical distribution system. The closure of the Benning Power Plant only affects the plant area.

How does this affect the Benning Consent Decree?
The Benning Consent Decree is a legal agreement between the District of Columbia's Department of the Environment and Pepco and PES that requires an assessment of environmental conditions known as a Remedial Investigation/Feasibility Study (RI/FS), at the Benning Road site and adjacent areas of the Anacostia River. The RI/FS will continue on schedule as the power plant decommissioning plan is implemented.

For more information contact:

Fariba Mahvi
Lead Environmental
Engineer & Benning Road
Project Manager

Donna Cooper
Vice President
District of Columbia Affairs