All gas stations with underground tanks with gasoline throughputs of more than 600,000 gallons per year must install an In-Station Diagnostics (ISD) system by the September 1, 2010 deadline.
Non-complying gas stations that are required to install ISD by the September 1, 2010 deadline, but will not complete installation by the deadline can continue to operate while working towards compliance provided the owner/operator enters into an ISD Compliance Agreement/Schedule with the District. The Compliance Agreement will require the owner/operator to achieve compliance no later than March 1, 2011.