Seeking data for future regulation, the US government has told factory-style farms that generate huge amounts of animal waste they can escape potentially large fines if their air pollution is monitored.

Associated Press reports that the offer by the Environmental Protection Agency is intended to produce the air-quality data needed for setting air-pollution standards for thousands of animal-processing farms, particularly hog, chicken, and egg operations.

By signing on, the farms, increasingly run by a concentrated few companies, pay US$2,500 into an EPA fund and agree to let EPA-approved contractors monitor the air.

Companies also would have to agree to pay a civil penalty of anywhere from US$200 to 100,000, depending on the size and number of farms they operate. Those fines would cover presumed violations, past and present, and fend off potential liability four years into the future, when EPA expects to issue its air standards.

Without the deal, EPA officials said, the air standards probably would take a decade or more to complete.

‘‘‘‘This is not a ‘‘pay up and get out of jail free‘‘ pass," said Thomas V. Skinner, EPA‘‘s acting chief of enforcement.

Environmentalists described EPA‘‘s offer as a ‘‘‘‘backroom deal" that will harm public health.

‘‘‘‘Rural families have been suffering from this pollution for years, and now they will have to wait," said Ed Hopkins, environmental quality director for the Sierra Club. ‘‘‘‘This is an agreement of the polluters, by the polluters, and for the polluters."