SUNDAY BRIEFING: An occasional look at Orange County issues : El Toro’s Toxic Mess

Cleaning up hazardous waste at El Toro Marine Corps Air Station will be a complicated and expensive process. Federal law dictates that the base remove its toxic waste, but environmental investigators have yet to decide the best way to dispose of contaminants that pose potential health and safety risks. Standard dumping practices in past decades included draining jet fuel and other toxic liquids into the soil and burying munitions. Here’s a look at the toxic sites and some scenarios for treating hazardous waste at El Toro.

El Toro Air Station History * Commissioned in 1943: The base was established as the center for the U.S. Marine Corps aviation operations on the West Coast. At the time, the surrounding area was primarily agricultural. Aviation activities generating hazardous waste included vehicle and aircraft maintenance, ground support maintenance, and aircraft corrosion control. * Pacific Fleet base: In 1950, El Toro was chosen as the site of a master jet air station and permanent center for West Coast Marine aviation to support the operations and combat readiness of the Pacific Fleet Marine Force. * Decision to close: Congress voted in September to close El Toro within the next four to six years.

Fast Facts * Area: 4,741 acres * Final closure date: As early as 1997, no later than 1999 * Housing: 7,250 military personnel and dependents * Personnel: 2,800 military and 1,900 civilian employees * Status: Superfund cleanup site * Total estimated cleanup cost: $250 million to $350 million, or more * El Toro’s Environmental Department: The department has tripled in size and budget over the past two years * Major contamination problem: Ground water * First air show: 1950

Where Things Stand The cleanup is in its second phase. Since the magnitude of hazardous waste is unknown, cleanup costs may rise as each step of the phase is completed.

Three Scenarios for Cleanup No overall decision has been reached on how to clean up the air base, although efforts already are underway to treat the plume of contaminated ground water using a desalter plant. Two other methods have been used to treat hazardous wastes around the country. How soil and ground water contamination can be removed: Desalter Project Working with the Orange County Water District, El Toro will co-finance a ground water treatment plant in Irvine to clean up the plume.

1) Water passes through membrane-like filter, removing salt and nitrates 2) Salt purged via sewer system to ocean 3) TCE rises with vapors 4) Chlorine added to water 5) TCE vapors captured 6) TCE incinerated off-site 7) Potable water dispensed through Irvine Water District Advantages * Provides clean drinking water for 100 years * Wells have been drilled Disadvantages * Only treats existing TCEs; does not eradicate source of contaminants * Release of brine into ocean may affect sea life Soil Vapor Extraction This method extracts hazardous chemicals without permanently removing the soil. It is considered by experts to be one of the most efficient and cost-effective methods of cleanup. 1. Vented pipes drilled into contaminated soil 2. Pump forces air through soil 2. Vacuum pump pulls noxious fumes into suction pipe 3. Carbon filter system cleans contaminated vapors 4. Treated air released into atmosphere Advantages * Least expensive treatment of contaminated soil * Known positive results * Can be quickly implemented Disadvantages * Steam injection may be needed to remove heavy hydrocarbons; contaminated water must be disposed * Results can depend on accuracy of well samples Underground Storage Tank Removal Underground tanks filled with toxic wastes are known to leak or spill. They can deteriorate quickly and must be emptied and removed. They also can be refilled with sand and reburied. 1. Trenches are dug around tanks; cranes hoist them free 2. Tank emptied of all liquids, vapors or sludge 3. Wastes collected in barrels; transported to authorized hazardous waste dump 4. Emptied tanks either filled with sand and reburied at site, or transported to authorized hazardous waste dump 5. Soil around removed tank transported to repository or treated with soil vapor extraction Advantages * Cost-effective * Known positive results Disadvantages * Residual contaminants may line emptied tank * Reburied tanks may continue to deteriorate

El Toro’s Hazardous Sites Twenty-five sites have been designated as definitely or possibly polluted. Buried weaponry: Used explosives and low-level radioactive waste Landfills: Burned and unburned waste including polychlorinated biphenyls (PCBs), petroleum hydrocarbons, organic solvents and paint residue Dust retardants: Petroleum wastes sprayed on dry roads to minimize dust Leaks and spills: Hydrocarbons; tetrachloroethylene; ferrocene; transformer fluid containing PCBs; diesel fuel; jet fuel; waste oil and solvent; other unknown chemicals Waste from crash crew practices: Crew practices extinguishing jet fuel fire in a simulated crash Buried waste: Jet fuel; lubricating oil; crankcase oil; battery acids; paints Sewage: Buried treated sewage sludge or leaking sewer lines Ground water contamination: Investigators determining source of high levels of trichloroethylene (TCE) in water table. Large plume continues to spread in Irvine.

Glossary Hydrocarbons: Any of a large group of compounds composed only of carbon and hydrogen Nitrates: Organic concentrate introduced in ground water and soil through use of fertilizers Organic solvents: Cleaning fluids that naturally break down in environment Polychlorinated biphenyls (PCBs): Used as fungicides and insecticides Tetrachloroethylene (PCE): Commonly used in dry-cleaning, and as a metal parts degreaser; found to cause liver cancer in mice Trichloroethylene (TCE): Probable human carcinogen found in paint removers, metal part degreasers and typewriter correction fluid Total petroleum hydrocarbons: A measure of the concentration of all petroleum constituents present in water, soil or air Volatile organic compounds (VOCs): Chemicals that readily evaporate into gases when exposed to air; includes tetrachloride, chloroform, PCE and TCE

Plume Poisons The Orange County Water District has documented five contaminants in the plume whose concentrations exceed health risk comparison levels set by the Environmental Protection Agency. Ranges are measured in ppb, or parts per billion.

EPA range of unhealthy Concentration levels Contaminant concentration levels in El Toro plume Carbon tetrachloride 0.4-61 0.27 Chloroform 0.1-14 5.7 Nitrate-N 100-14,000 10,000 Tetrachloroethylene trace-81 0.7 Trichloroethylene 0.1-89 3.2

What Tustin Air Station is Doing The Marine Corps Air Station at Tustin faces similar contamination problems. Tustin is treating one toxic site using an innovative soil vapor extraction procedure. Holes are drilled and the site is covered with concrete and/or bricks to prevent erosion while treated air escapes into the atmosphere.

Sources: El Toro Marine Corps Air Station; Mission Geoscience Inc.; Orange County Water District; California Environmental Protection Agency; Researched by APRIL JACKSON / Los Angeles Times