WORRIES PROMPT STUDY; FIRM WILL CHECK DUMPS FOR HAZARDOUS MATERIALS.

Byline: David Greenberg Daily News Staff Writer

Concerned about possible health hazards, Ventura County supervisors have hired a company to investigate 15 closed dumps - including three in eastern Ventura County.

Bryan A. Stirrat & Associates, a Diamond Bar-based environmental engineering firm, will be paid $52,533 to determine if hazardous materials and natural methane gas exit in dangerous levels and require removal or further capping.

``Some of these landfills were privately operated before the county took them over,'' said Greg Warren, a county waste management analyst.

Excess amounts of methane gas can be removed by laying pipes underneath the surface, allowing the substance to be collected and burned.

``(The dumps existed) before there was any control in where the materials were dumped,'' said Supervisor Frank Schillo.

The study is expected to be complete by spring - in time for county budget makers to fund the remediation of any hazards when creating their fiscal 1999 spending plan.

Stirrat would charge $3,500 for each additional dump it examines.

County officials said the sites have been closed for decades.

The three east county dumps are the Tierra Rejada Landfill off Route 23 in the ``green belt'' area near Moorpark; the Thousand Oaks County dump off Westlake Boulevard in the Lang Ranch area; and the Somis Dump in the area of Highway 118 and Lewis Road.

A landfill dating back to at least the early 1930s was discovered by workers constructing the 118 connector road in the early 1990s. Although no significant levels of hazardous waste were uncovered, Supervisor Judy Mikels said, ``It slowed down the project and cost more bucks than they were counting on.''

Schillo said he does not believe the study will reveal any major problems.

``It's just done out of an abundance of caution,'' he said.

Added Supervisor Judy Mikels, ``The ones that are scary are the ones we don't know about.''