Superfund Site: AIR FORCE PLANT #4 (GENERAL DYNAMICS), FORT WORTH, TX
Superfund Site Profile
The Air Force Plant #4 (AFP4) site is located in Tarrant County near Fort Worth Texas. AFP4 is a 760-acre facility that has manufactured military aircraft since 1942. The U.S. Air Force (USAF) currently owns the facility; Lockheed Martin Corporation operates it. Operations contaminated sediments, surface water and ground water with hazardous chemicals. A facility-wide ground water plume generally defines the site boundaries. Following construction of the remedy, long-term cleanup actions are ongoing.
The Third Five Year Review Report for the Site was completed in September 2014. AFP4 is currently in the Long-Term Remedial Action (LTRA) phase of the Superfund process. EPA concurred on the Third Five-Year Review Report for AFP4 on September 30, 2014. A full-scale ground water pump and treat system has been installed at the east parking lot. The system is presently operating successfully.
A Dense Non-Aqueous Phase Liquid (DNAPL) Electrical Resistive Heating (ERH) and Soil Vapor Extraction (SVE) System has proven to be effective in lowering contamination beneath Building 181. The USAF installed the indoor application of subsurface heating to enhance the recovery of TCE. An approximate 22,000 sq. ft. area beneath Building 181 was heated to 90 degree C by 73 electrodes placed at depths of 35 feet for eight months. A vacuum enhanced vapor/ground water recovery system was operational from 1993 - 2002.
The USAF installed a 1,170 foot long, 2 foot wide, 35 foot deep Permeable Reactive Barrier (PRB) wall across the leading edge of the southern lobe of the TCE plume in 2002. The leading edge of this plume, as defined by the TCE maximum concentration limit of 5.0 μg/L, has since retracted approximately 1,500 feet across the Base Realignment and Closure (BRAC) property. AFP4 achieved Construction Completion on September 15, 2006.
Air Force Plant 4 (AFP4) is located in Tarrant County, six miles northwest of Fort Worth, Texas. The communities of White Settlement, Lake Worth, Westworth, River Oaks, and Samson Park lie within a 3-mile radius of AFP4. Naval Air Station Fort Worth (formerly Carswell Air Force Base) is located adjacent to AFP4 to the east. Approximately 13,000 people reside in White Settlement, Texas.
AFP4 is a government-owned, contractor-operated facility consisting of 760 acres. The facility has manufactured military aircraft since 1942 and is currently owned by the U.S. Air Force (USAF) and operated by Lockheed Martin Corporation. Approximately 15,000 people are employed at AFP4.
Six schools are within a 2-mile radius of AFP4 and the closest school is located 1/2 mile south of the facility. The areas south and west of AFP4 are mainly residential. Lake Worth, bordering AFP4 to the north, provides recreational boating and fishing. This lake also supplies municipal water to the city of Fort Worth, Texas and is a recharge source to the underlying Paluxy Aquifer. The city of White Settlement, Texas, receives municipal water supply from wells completed in the lower Paluxy aquifer.
The AFP4 Superfund Site is generally defined by the base wide trichloroethene (TCE) ground water plume. TCE and its degradation compounds have been detected beneath AFP4 in the shallow Terrace Alluvium Aquifer, the Upper Sand ground water of the Paluxy Aquifer, and in the upper Paluxy Aquifer above safe drinking water levels. The lower Paluxy Aquifer is used for drinking water and is not contaminated. The nearest drinking water well is located approximately 1/4 of a mile up-gradient from the site. Contaminants have not been detected in this well.
The remediation of ground water contamination from AFP4 will protect the drinking water resource for approximately 13,000 people living within one mile of the site, as well as an important recreational area used by many Tarrant County residents.
National Priorities Listing (NPL) History
NPL Proposal Date: October 15, 1984
NPL Final Date: August 30, 1990