A public interest group concerned about slipshod health standards and filthy conditions in the nation's slaughterhouses has filed suit against the Agriculture Department to obtain a report on its beef inspection procedures.

The suit is the latest flurry in a long-running battle pitting the USDA against consumer groups and dissident federal food inspectors who charge that the department's Streamlined Inspection System is putting dirtier and more dangerous beef in supermarkets.

Partly in response to public criticism, the department last year contracted the National Academy of Sciences to study the inspection system to ascertain whether it posed unacceptable food safety risks.

The department later gave the academy its own report on the program, but refused to make it public. This prompted the Government Accountability Project to file suit last week in U.S. District Court to obtain the report under the Freedom of Information Act.

"We have very strong suspicion that the USDA defense of the Streamlined Inspection System is a bureaucratic bluff," said Thomas Devine, the project's legal director. "The reason they won't release it is that the assertions they make couldn't withstand outside scrutiny."

Agriculture Department spokesman David Schmidt said, however, that the agency had decided not to release its report until the academy had finished its study. The academy said publication was expected at the end of September.

"Releasing the report would compromise and politicize the results of a scientific study," Schmidt said. "We don't feel we need to release it to a group that has no expertise in the subject."

Although the Government Accountability Project is legally registered as a general service public interest group, it is better known as an advocate for "whistle-blowers" -- government officials who call attention to wrongdoing in their own bureaucracies.

And in the Streamlined Inspection System debate, the project has counted on the affidavits and other written statements of several dissident inspectors from the Agriculture Department's Food Safety and Inspection Service.

Devine charged that the department has accepted "at face value" reports from companies testing the inspection system. These reports, he said, "say the beef is getting cleaner and cleaner," while the accountability project's evidence showed "the beef has never been filthier."

The USDA proposed the Streamlined Inspection System in the early 1980s as a means to modernize a slaughterhouse inspection system that had remained virtually unchanged since the department first began examining beef in 1906. The new system was first tried in 1984, and is currently being tested in five meat packing plants.

The essential difference between the new system and "traditional" procedures is that the company's quality control workers do many of the tasks once reserved for department inspectors.

The Government Accountability Project has charged that the quality control workers are badly trained and reluctant to do anything to beef carcasses that will slow or stop "the line" of beef as it travels from the slaughterhouse floor to refrigerators.

"Under the Streamlined Inspection System, the line speeds are increased with little or no actual physical contact by our trained food inspectors," said David Carney, a USDA inspector based in Salem, Ohio, and vice chairman of the 6,000-member Food Inspectors' Union. "We are simply monitoring what the company does."

In the past, Carney said, inspectors examined each beef carcass for a variety of diseases, palpating various organs and making incisions to check for measles, pneumonia, abcesses and a variety of other diseases and contaminants.

Under the new system, Carney and other inspectors reported, company quality control people make bad incisions, often piercing stomachs, bladders and bowels before the inspectors can look at vital organs. Carcasses that reach the inspection stations are often covered with feces, vomit and urine, Carney said.

The Streamlined Inspection System has also proved controversial within the beef industry. The five pilot plants include two belonging to Monfort, in Colorado and Nebraska, two Texas plants belonging to Excel and a National Beef plant, in Kansas.

But IBP, the biggest meat packing firm in the country, discarded the Streamlined Inspection System after a short trial. In a Jan. 16 letter to the USDA, IBP Assistant Vice President James Lochner said his firm had "a major concern that the proposed changes will not improve protection of public health.

"We agree that it is the company's responsibility to control hygiene and remove contaminants that are inadvertently put on the carcass," Lochner said. "However, this is a major responsibility that all plants may not be able to accomplish without close scrutiny by FSIS {Food Safety and Inspection Service} inspectors."

At Monfort, however, quality control vice president Rod Bowling said the new system had given the company "an opportunity to cooperate with the USDA to improve both the process and the product."

The inspectors, Bowling said, now have "more time to look at pathology." As a result, he added, Monfort's data showed incidence of salmonella and other contaminants had plummeted in the pilot plants.

He said the Streamlined Inspection System had caught Monfort "in the middle of a dispute between USDA and its inspectors," but dismissed criticisms by the Government Accountability Project, which he said was staffed with people "not trained in microbiology or anything else."

"My PhD is in food science," Bowling said. "We're not a bunch of jerks that came in on a load of canteloupe."