The Environmental Protection Agency has discovered a new weapon to force recalcitrant industries to comply with air and water pollution laws: the blacklist.

Hitherto neglected provisions of the 1972 Water Act and the 1870 Clean Air Act allow EPA to list serious violators, making them ineligible for federal contracts, subcontracts, grants for loans.

Last week EPA announced it has blacklisted an Allied Chemical coke plant in Ashland, Ky. The plant sells coke to Armco Steel Corp., which uses it to make steel under Defense Department subcontractors. EPA notified Armco not to use Allied coke in future government contracts.

The Allied plant is the first in the nation to be blacklisted for air pollution. Four months ago EPA used the blacklist for the first time against two water polluters, the Del Monte and Star-Kist tuna processing plants in Puerto Rico.

If used extensively, the blacklist could conceivably affect millions of dollars in federal contracts, because hundreds of industries continue to pour chemcials and other wastes into the air and water in defiance of EPA orders. However, the agency is proceeding cautiously.

"Blacklisting has tremendous potential for getting serious, continuing violators to come into compliance," said Rebecca Hamner, chief of EPA's Office of Federal Activities. "Company officials don't like being blacklisted. Their stockholders don't care for teh bad publicity."

However, the agency has no intention of immediately listing for example the 1,450 industrial and municipal plants that are behind on air pollution clean-up shedules or the 900 industrial plants that are violating water pollution laws.

"We're going to concentrate on the serious major cases," Hammer said. "It's not a punitive program to get the little guy. The principal value of the list is as a threat."

In a Jan 19, memo the day before he left office, EPA Administrator Russell Train directed the agency's regional offices to take a tougher enforcement stand. "I want to make it clear there will be a 'presumption of listing' for all serious cases of non-compliance" with air and water pollution orders, Train wrote.

He attributed an agreement with Inland Steel Corp. last fall on an air pollution clean-up schedule to an EPA letter requesting information on Inland's federal contracts. The threat of listing and the resulting publicity "appear to have significant influenced the company's decision to enter into a consent order," Train wrote.

Likewise, Train, "A similar letter to the recalcitrant state prison facility in Stillwater, Minn., indicating the potential loss of Law Enforcement Assistance Administration grants, has resulted in compliance efforts at that facility."

EPA's decision to step up use of the blacklist is due in part to pressure from the national Resources Defense Council, a non-profit environmental law firm here. An 11-page letter to EPA Dec. 21 accused the agency of "underutilizing" the blacklist.

Congress' conference report on the Water Act stated, "The federal government will not patronize or subsidize polluters through its procurement practices and policies," NRDC pointed out. Since October, 1975, federal contracts have required companies to confirm that they are not blacklisted.

Defense Council attorney James T.Banks estimated the hundreds of plants could be listed under the water law alone.

EPA declines to estimate the number of companies eligible for blacklisting. Hammer said, "The purpose of the list is to get people to clean up. It can be effective even if you don't list a lot of companies."

The list she said, will be an incentive for companies to avoid delaying tactics and drawn-out court battles over the schedules that EPA requires for installing pollution-control equipment.

No estimate is available on the total value of contracts that might be jeopardized by the blacklist. Except in the case of criminal convictions, which are rare in pollution cases, the black-list affects only contracts and subcontracts over $100,000.

EPA can blacklist individual plants, not entice companies. An offender can appeal the listing, but after a formal hearing of the evidence, EPA makes the final decision.

Norman Herington, Allied Chemical's director of corporate information, said "we don't know of any direct immediate effect" on the black-listed facility, the Semet-Solvay Division plant in Ashland. However, the plant, which has been fighting EPA in court over coke emissions, still sells its coke emissions, still sells its coke to Armco.

EPA's order forbidding Armco to use Allied's coke in its future federal contracts or subcontracts "sounds like a secondary boycott," Herington said. "We question whether that is legal." Don Easterly, Armco's spokesman in Middletown, Ohio, declined comment on the case.

The two tuna-processing facilties listed for water pollution are cooperating with EPA, Hamner said, and will be taken off the list as soon as final agreement is reached.

EPA had sued Del Monte for dumping 2.5 million gallons for processing wastes daily into Puerto Rico's Mayaguez Bay. Darwin Hanson, a spokesman at company headquarters in San Francisco, said the effect of blacklisting the tuna, subsidiary is "quite minimal" because the facility has no federal contracts or subcontracts.