A review of Environmental Protection Agency records shows six small Montana water systems have reported lead levels above federal standards since 2013.

But two said their water is used for restrooms or industrial processes, not for drinking. Two others said errors put them on the list and that their water was within EPA guidelines.

An Associated Press analysis of EPA data nationwide found that nearly 1,400 water systems serving 3.6 million Americans have exceeded the federal lead standard at least once between Jan. 1 2013, and Sept. 30, 2015.

In Montana, the Two Dot Water Users Co., which serves 50 people in Wheatland County, reported lead levels that exceeded the federal standard of 15 parts per billion sometime between January 2013 and mid-2015.

But system operator John Crowley said the level dropped to 1.4 parts per billion by October 2015.