MONTICELLO (AP) - Operators have temporarily shut down the Monticello nuclear power plant to replace a safety relief valve.

Xcel Energy says the valve protects the plant's main steam line system from over pressure conditions. The Minneapolis-based company says the shutdown is not expected to be lengthy, and poses no danger to the public or plant workers.

Whenever a power plant shuts down for maintenance, Xcel Energy purchases electricity from the Midwest Independent Transmission System Operator or other utilities, or increases production at its other plants.

Xcel Energy owns and operates the Monticello plant, about 40 miles northwest of Minneapolis.

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