DRYDEN CLEANUP PROPOSED CONTAMINANTS DETECTED IN GROUNDWATER.

Byline: Jim Skeen Staff Writer

EDWARDS AIR FORCE BASE - Environmental officials are proposing a $1.9 million cleanup plan for underground water tainted with solvents from the early days of what is now the NASA Dryden Flight Research Center.

Trichloroethylene, or TCE, has been detected in concentrations as high as 13,000 micrograms per liter in groundwater beneath the research center's flight line, well over the state cleanup standard of 5 micrograms per liter.

The water is not used for drinking and the solvent plume is not considered a health hazard because workers cannot come into contact with it, but must be cleaned up under state regulations, officials said.

The cleanup option preferred by government officials is to use 23 existing wells in and around the plume to inject an agent called potassium permanganate to break the TCE down into harmless byproducts. Potassium permanganate is used in deodorizers and disinfectants.

``We have done a number of small-scale treatability studies,'' said Dan Mullen, environmental manager for Dryden. ``This is the most effective technology.''

The TCE is believed to date from the 1940s and 1950s from operations such as repairing and washing aircraft. Another potential source is a former motor pool gas station where three underground tanks might have leaked.

In a draft of the proposed cleanup plan, NASA and the Air Force looked at five options for dealing with the plume, ranging from taking no action to a $71.5 million plan that called for installing 2,550 wells for injecting chemicals to treat the TCE.

A meeting to take public comment on the plan is scheduled for 6 to 8 p.m. on April 27 at California City's City Hall, 21000 Hacienda Blvd.

Dryden officials plan to hold an in-house meeting to tell its employees about the cleanup.

Jim Skeen, [phone]

james.skeen(at)dailynews.com