MINNEAPOLIS (AP) – Xcel Energy Inc. says federal regulators have renewed the operating licenses for its Prairie Island nuclear plant for another 20 years.

In its announcement Tuesday, Xcel Energy says it plans to invest at least $500 million in the 40-year-old plant through 2015.

Judy Poferl, president and CEO of the utility’s Northern States Power Co.-Minnesota subsidiary, says additional investments will be made if the NRC approves an increase in the plant’s generating capacity. The company plans to apply for that later this year.

The renewal was opposed by the Prairie Island Indian Community, whose reservation is next to the plant. Tribal officials say they have longstanding health and environmental concerns they don’t believe have been adequately addressed. They include long-term exposure to low-level radiation and radioactive contamination of groundwater at the site.

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