(September 23) The county has increased the contract it has with the environmental engineering firm working on contamination issues at Chino Airport by $290,000, taking the entire contract amount from $1,695,880 to $1,985,880.
According to James Jenkins, the director of the San Bernardino County Department of Airports, the San Bernardino-based firm of with Tetra Tech, Inc. has already been paid $1,695,880 for historical site assessment, environmental site assessments, environmental compliance audits and the conducting of a monitoring program at Chino Airport.
On October 31, 1990, the Regional Water Quality Board issued Clean-up and Abatement Order No. 90-134 to the county of San Bernardino for suspected contamination of ground water beneath Chino Airport. At that time, it was thought that the groundwater had been contaminated due to past usage of perchloroethylene/trichloroethene.
Perchloroethylene/trichloroethene were solvents that were commonly used in the aeronautic industry from the 1930s until the 1990s.
The county complied with the order by conducting activities at the Chino Airport to identify all potential sources of contamination, characterizing identified source areas, remediating discovered soil contamination; characterizing ground water contamination; monitoring groundwater contamination; and mitigating identified groundwater contamination within the confines of the airport grounds.
On October 17, 2006, the San Bernardino County Board of Supervisors approved a $200,000 contract with Tetra Tech, Inc. to conduct a groundwater assessment of the water table at the Chino Airport and investigate possible sources of contamination from the airport property. On September 11, 2007, the board approved a $200,000 amendment to extend the assessment services, including investigation, characterization, testing and quarterly report preparation required to identify and mitigate soil and water contamination together with preparing bid documents for an additional 24 months. The county received a new clean-up and abatement order from the water board in June 2008. That order required the county to conduct investigation, containment and mitigation of volatile organic compounds (VOC) down gradient of the Chino Airport.
In 2008, the county installed nine monitoring wells on and adjacent to Chino Airport to assist in the vertical characterization of the suspected contamination plume.
On September 22, 2009, the board approved a $185,000 amendment to extend the assessment services with Tetra Tech an additional 12 months to continue its efforts.
In 2010, the county installed 10 additional monitoring wells on and adjacent to the Chino Airport to assist in the horizontal characterization of the VOC impacted groundwater plume.
The game changed when on the afternoon of July 22, 2010, during trenching for installation of a storm drain pipeline for a new Southern California Edison facility, the first three of what turned out to be 51 drums of what is believed to have been napalm were discovered to have been buried at the airport. The county of San Bernardino Department of Airports was notified and it contacted the county fire department’s hazardous materials division and Tetra Tech. Tetra Tech retained Double Barrel, a commercial hazardous materials emergency responder, to assess the situation.
Additional drums were discovered that day and by sunset on July 22, 2010, eight buried drums had been removed from the excavation. The drums did not have lids and contained soil on top of a tan resinous material. The contents of the drums were field tested using a chemical identification kit and determined to be a non-explosive, flammable, non-corrosive, organic resin-type material.
Soil samples were delivered to Microbac Laboratory in Riverside for analysis. Microlab determined the drums contained high concentrations of benzene together with lesser amounts of toluene, ethylbenzene, xylene, styrene, 1,2,4-trimethylbenzene, and naphthalene, leading to the conclusion that the tan resinous material was a jellied fuel mixture, most likely napalm. In all, 51 barrels were unearthed.
In 2013, the county increased its contract with Tetra Tech, Inc. to $1,695,880 and extended it through April 30, 2015.
This week, Jenkins told the board of supervisors that Tetra Tech has essentially completed work that exhausts its previous contract allotment. He asked the board to appropriate another $290,000 to “provide additional funding necessary for the continuation of engineering, testing, monitoring well installation oversight and inspection services resulting from the characterization of a plume of perchloroethylene/trichloroethene (PCE/TCE) contamination extending south of the Chino Airport.”
Based upon Jenkins’ report to the board of supervisors, it is not clear whether there has been any cross-contamination involving the perchloroethylene/trichloroethene and the napalm. His report referenced only the perchloroethylene/trichloroethene contamination.
“The groundwater is suspected to have been contaminated due to past usage of PCE/TCE,” Jenkins wrote. “The county has complied with and continues to comply with this order by conducting activities at the airport to identify all potential sources of contamination; characterize identified source areas; remediate discovered soil contamination; characterize ground water contamination; monitor ground water contamination; and mitigate identified ground water contamination within the confines of the Chino Airport, located at 7000 Merrill Avenue, Chino.”