[10] The Monticello section of the Mississippi River remains unfrozen during winter and attracts hundreds of trumpeter swans, largely due to warm water discharged by the nuclear plant.

[11] In November 1971, 50,000 gallons of "low-level" radioactive water was released into the Mississippi River by the facility in order to conduct repairs.

[13][14] Roughly 1,300 gallons (4.9 cubic meters) of radioactive water which accidentally leaked from the plant into the Mississippi River in an incident on 5 May 1982, was determined to be "no threat" to the public.

Emergency response teams at the station deemed that the event was likely caused by inadequate welds at the time of installation and fatigue due to vibrations over the life of the plant.

[citation needed] Construction of the on-site independent spent fuel storage installation (ISFSI) pad began in June 2007.

[16] On September 18, 2008, an employee for a rental equipment company was electrocuted by one phase of the 115-kV power line outside of the plant due to a lack of situational awareness.

[17] In February 2011, the site's plant officials determined that four control rod blades could be affected by a potentially substantial safety hazard.

[18][19] In 2006, Xcel Energy proposed a series of upgrades to the plant in order to increase its output and extend its life for an additional 20 years.

"[24][25][26][needs update] In December 2023, Xcel Energy was fined $14,000 by the Minnesota Pollution Control Agency for not obtaining a permit before pumping contaminated groundwater into temporary holding tanks.