The supercharged discussion about building a major commercial airport at the El Toro Marine Corps Air Station usually focuses on noise, safety and traffic. But perhaps the greatest unknown at the base is not what might happen above the ground, but what could be buried beneath it.
More than $200 million has been spent over 15 years to clean up the base, and millions more must be spent to rid the site of hazardous wastes, cover two large landfill sites and dispose of heavy underground fuel tanks.
But there is a dispute about how to seal off the two landfill sites, which have never been tested and have unknown buried contaminants. How well the landfills are taken care of may have consequences affecting public health and how the base can be used.
This week, military and airport officials will discuss cleanup issues at the Santa Ana Hall of Administration. An overall El Toro briefing is scheduled for the Orange County Board of Supervisors' meeting today.
Until now, the cost and the burden of cleanup have been shouldered by the Department of the Navy, which owns the 55-year-old base. If all goes according to plan, in July 1999, 3,700 acres of the facility will be turned over to the county, which will be responsible for developing the base and repairing environmental damage.
The military has pledged to clean up known contamination to the highest level, so that residential housing could be built there in addition to a commercial airport.
Marine officials say 85% of the contaminated areas of the base have been cleaned, which environmental officials do not dispute. The other 15% of the contaminated property includes 12 acres containing the landfills, a miles-wide plume of tainted ground water and 53 underground storage tanks, containing jet fuel and oils, that are slated for removal.
The Marines plan to cover the landfills with four feet of earth, but environmental officials say that will not be sufficient because the county plans to build a golf course and a light industrial area next to the landfills and near the proposed commercial airport.
Environmental officials fear that if moisture comes in contact with the contaminants, methane could be released into the air. They have proposed that the military place a plastic liner on the landfill next to the golf course and an asphalt cap in the other landfill--something the military says it cannot afford to do.
"It doesn't do the community any good for the military to say, 'We have met our responsibility,' " said Greg Hurley, an Orange County environmental lawyer and co-chairman of the Restoration Advisory Board, which oversees the military cleanup of the property. "What good is that if we can't use [the land]?"
Considering that El Toro is on the nation's Superfund list of most dangerous hazardous-waste sites, county officials know they must clearly understand the environmental mess they could inherit and how that could affect their plans for development.
County officials like Chief Executive Officer Jan Mittermeir remember the $4 million the county spent unexpectedly to clean decades-old ground water contamination found during the construction of the terminal that opened in 1991 at John Wayne Airport.
That is why county staff hired an engineering firm this month, to analyze the landfills. Whatever data the engineers gather won't be disclosed to the public, because county attorneys regard the information as a confidential part of efforts to determine the county's potential legal liability for cleaning up contamination.
The contract created a political controversy because the engineering firm was hired by county officials without the approval or advance knowledge of the Board of Supervisors. Supervisor Todd Spitzer questioned why the work--which will cost up to $100,000 this year--was authorized without the board's blessing. The board generally must review contracts of more than $25,000.
Spitzer argued that the elected officials and residents must be made aware of the hazards the landfills could pose to the public before the Marines turn over the property to the county.
"The more difficult it is for us to address this [contamination] issue, the more difficult it will be to decide what sort of land uses can be developed at the base," said Spitzer, a staunch airport opponent.
Besides dealing with the landfills, the Navy is working with the federal Environmental Protection Agency to begin soil cleanup to remove "volatile organic solids"--chemicals that readily evaporate when exposed to the air--from the base, said Tom Huetteman, Navy section chief of the EPA's Superfund division.
Federal and state environmental agencies are working with the Orange County Water District to build a treatment plant in Irvine to clean up a 3 1/2-mile plume of contaminated ground from El Toro water under the Irvine neighborhood of Woodbridge.
Nearly 10 years ago, the plume was found to contain trichlorethylene, a toxic solvent used by the Marines to degrease aircraft.
As recently as the 1970s, there were no laws against dumping hazardous chemicals into the ground at the base. For many years, that is how jet fuel, used motor oil and metal were disposed of, as well as potentially cancer-causing industrial solvents, polychlorinated biphenyls (PCBs) and low-level radioactive waste.
The Marines' record of dealing with environmental contamination has been mixed.
The El Toro base has been cited twice since its designation in 1990 as a Superfund site for illegal handling of hazardous waste.
In 1993, the Marines were ordered by the California EPA to pay an $80,500 fine for their second citation for mishandling hazardous waste.
Military officials are determining where contaminated sites might be located, based on dumping records and other data, Huetteman said.
Hurley, however, said many communities nationwide have suffered through the costly and difficult problem of discovering new contamination after they take ownership from the military and begin their own projects.
"It's inevitable that when work goes on there we are going to hit contamination that we didn't know about," Hurley said.
Although the EPA is satisfied with the military's solution for cleaning up the soil, the biggest environmental unknowns at the base are the landfills.
Because there appears to be no ground water contamination or vapor escaping from the dumps, the Marines plan to cap the landfills with a four-foot soil cover, a lesser remedy than asphalt, concrete covers or synthetic liners.
State EPA officials say a membrane layer would add $500,000 to the $5.2 million the military will spend on the golf course landfill. An asphalt layer would cost about $1 million more.
California EPA officials say once the Marines relinquish the base, the county must prove that it will take care of any potential problems with the landfills.
"They must show us how they can control the irrigation and show us how it would not disturb" the contaminants, said Tayseer Mahmoud of the California EPA Department of Toxic Substances Control. "They would be responsible in that case."