This action responds to petitions for reconsideration, of the final rule, published in the Federal Register on November 21, 1988 (53 FR 47084), requiring operators of pipeline facilities for the transportation of natural gas or hazardous liquids and operators of liquefied natural gas facilities to have an anti-drug program for employees who perform certain sensitive safety-related functions covered by the pipeline safety regulations. On April 13, 1989, the implementation dates contained in the final rule were modified to permit reevaluation of the rule in light of recent decisional law and consideration of issues raised by the petitions for reconsideration. The petitions for reconsideration are granted in part and denied in part, for the reasons set forth below. This document amends the final rule to implement those portions of the petitions granted, and makes other clarifying changes and corrections.