EA prepared drawings and plans for implementation of a high hazard underground storage tank and pipeline decontamination/remediation project of five 1.74-million gallon (each) underground storage tanks and associated underground pipeline with >8,853 linear feet of 6-inch pipe, >26,800 linear feet of 8-inch pipe, and >2,065 linear feet of 3-inch pipe at the former Monaca Air Force Petroleum, Oil, and Lubricant Distribution Facility. EA obtained Pennsylvania Department of Environmental Protection approval for in-place cleaning of five 1.74-million-gallon underground storage tanks and associated vaults. More than 26,000 feet of API-lined welded gasoline piping was cleaned and sealed. EA implemented cleaning strategies that resulted in the removal/disposal of 130 tons of petroleum-contaminated soil and debris, and 246,000 gallons of non-hazardous No. 2 fuel and water mixture. Fuel was separated and taken offsite for recycling. Water was treated onsite using a water treatment system with activated carbon. EA backfilled excavations in lifts with compaction to prevent future settling.