The Environmental Protection Agency is accusing a second oil company of polluting the San Juan River in southeastern Utah: Mobil Exploration & Producing U.S., a subsidiary of Mobil Corp.

Last week, the U.S. Attorney's Office, acting on behalf of the EPA, filed a federal civil suit against Texaco, charging it spilled oil and water used in production and did not comply with environmental laws. On Monday afternoon federal lawyers filed another civil suit in U.S. District Court in Salt Lake City, making similar claims against Mobil.Mobil, based in Dallas with a field office in Cortez, Colo., violated the Clean Water Act in its production at the Aneth oil field beside the San Juan River, the suit charges.

Beth Ann Black, a spokeswoman for Mobil in Dallas, said Tuesday the company is not commenting on the suit. "Right now we have not seen the lawsuit and therefore we cannot comment in detail at this time."

The allegations focus on two tracts that Mobil leases on the Navajo Indian Reservation, the McElmo Creek Unit and the Ratherford Unit. These are major operations, with hundreds of producing and injection wells plus batteries of storage tanks.

On Sept. 4, 1995, 2,000 barrels of production water and 450 barrels of oil discharged from the Ratherford unit, but Mobil "failed to provide notification of this discharge within 60 days to EPA's regional administrator," as required by law, the suit says.

When the EPA inspected the units on March 3 and 4, 1997, it found a host of violations, according to the suit:

- Lack of a sufficient diversion system at the McElmo Creek storage facility.

- No secondary containment system at loading and unloading areas for a bulk fuel storage facility at McElmo's Area One Tank Battery.

- Stained soil and leaking valves.

- Corrosion of several tanks.

- A leaking seam on a tank at the Ratherford Unit.

Also, Mobil failed to properly operate gauges at one of the tanks, "resulting in a overflow," says the suit. It also claims the company did not connect all tanks to a computerized monitoring system at the Gas Processing Plant.

Altogether, 73 spills of varying quantifies and types of pollution occurred between Jan. 19, 1991, and Feb. 2, 1998, it adds. Federal lawyers are asking for a court injunction to prevent future discharges and for damages. Amounts sought are up to $25,000 for each spill that happened before Jan. 30 1997, and up to $27,500 per day for violations of the Clean Water Act that happened after that time.