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Nuclear Sites
Utility Owned:
Arkansas Nuclear One
Grand Gulf
River Bend
Waterford 3
Entergy Wholesale Commodities Owned:
Indian Point Energy Center
Vermont Yankee
Entergy Wholesale Commodities Management Services:
Arkansas Nuclear One

Grand Gulf Nuclear Station

In July of 1985, Grand Gulf Nuclear Station in Port Gibson, Miss., made history by becoming the first and only nuclear power plant to produce electricity in Mississippi. Grand Gulf marked another milestone by completing a power upgrade June 16, 2012, that makes it the largest single-unit nuclear power plant in the country and fifth largest in the world. Grand Gulf is owned and operated by System Energy Resources, Inc. (90 percent) and South Mississippi Electric Power Association (10 percent).

The project was one of the largest expansions of a nuclear power plant in U.S. history and increased Grand Gulf’s production by more than 13 percent, bringing total output to 1,443 megawatts. The action was part of Entergy’s overall plan to close a growing gap between the amount of power the company produces and the amount that customers use. Today, Grand Gulf is the most affordable source of electricity in Mississippi.

One of Entergy’s core values is a commitment to communities, and Grand Gulf and its employees maintain a strong presence in Port Gibson and Claiborne County. A recent Communitas Award for Leadership in Community Service applauded Grand Gulf’s community efforts that include a partnership with a local university on a health physics internship program, the establishment of an economic development organization for the area and a multitude of support programs for public education, the arts and low-income customers.

Grand Gulf Nuclear Station
Port Gibson, Miss.



System Energy Resources, Inc. (90%)
South Mississippi Electric Power
Association (10%)

Maximum Dependable Capacity: 1,478 MW megawatts electrical

Reactor Type:

Boiling Water Reactor

Reactor Manufacturer:

General Electric

Turbine Generator Manufacturer:

Kraftwerk Union


Bechtel Power

Commercial Operation Date:


License Expiration Date:


Cooling Water Source: Collector Wells
Number of Employees: 675
Counties included in Emergency Planning Zone: Claiborne County, Miss., and Tensas Parish, La.

Environmental Impact

Generating electricity with nuclear energy prevents the emission of pollutants like sulfur dioxide (SO2) and nitrogen oxides (NOx) and greenhouse gases like carbon dioxide (CO2) associated with burning fossil fuels.

During 2011, environmental emissions avoided due to nuclear power plant operation in Mississippi included 12,000 tons of sulfur dioxide, 8,000 tons of nitrogen oxide and 7 million metric tons of carbon dioxide.*

Emissions of SO2 lead to the formation of acid rain. NOx is a key precursor of both ground-level ozone and smog. Greenhouse gases like CO2 contribute to global warming.

* Source: Emissions avoided by nuclear power are calculated using regional fossil fuel emissions rates from the Environmental Protection Agency and plant generation data from the Energy Information Administration.

To view the NRC environmental assessment related to the Grand Gulf extended power uprate, go to http://pbadupws.nrc.gov/docs/ML1026/ML102660405.pdf .

To view the NRC environmental assessment related to Grand Gulf’s license renewal, go to http://pbadupws.nrc.gov/docs/ML1332/ML13328A002.pdf .