This is an Administrative Compliance Order pursuant to the Safe Drinking Water Act issued to the City of Vallejo, California. The violations involve exceedances of the 3rd Quarter 2004, 4th Quarter 2004 and 1st Quarter 2005 running annual average MCLs for total trihalomethanes, among other things, at the City's Vallejo Lakes water system (Green Valley Water Treatment Plant). The Order directs the city to submit a plan within 21 days of receipt of the Order that explains how the city will return to compliance with the MCL and other items by Septemebr 30, 2005.