The La Plata-Archuleta Water District has mailed a letter to about 1,500 households in southeastern La Plata County, giving them an opportunity to opt out of a proposed drinking- water system. “This isn't new," water district president Dick Lunsford said by telephone. “This is the third chance people have had to drop out." The first chance was before a hearing of La Plata County commissioners. The second opportunity was before a court hearing, Lunsford said. The latest mailing doesn't go to all residents because some homeowners already have removed their property from the district. “We're trying to be fair," Lunsford said. “Some people may not need water now, but they could come back in later without a penalty." The deadline for returning the letter is March 15, he said.