The Colorado Petroleum Association (CPA) today dropped its bid to get the state to roll back its rule for proper disposal of pit liners used in the oil and gas drilling process. Rule 905 was one of the revised oil and gas drilling regulations most criticized by the industry after the new, more environmentally stringent rules went into effect in the spring of 2009. The CPA withdrew its petition at today’s Colorado Oil and Gas Conservation Commission (COGCC) meeting, eliciting praise from the environmental community.