Approval of new operating guidelines that will bring a mass burn plant into compliance with state and federal air quality standards could come by the end of July.

Officials of the Davis County Solid Waste Management and Energy Recovery Special Service District hope to get a revised permit in place before Aug. 15, when an extended contract agreement with the plant contractors is to expire. The agreement could be extended, but officials hope that will not be necessary.The new standards are being sought because it has been determined that the standards governing nitrous oxide were based on faulty calculations from engineering data available when the original permit was issued in 1984.

That permit limits the plant to an emissions rate of 75 parts per million on nitrous oxide. The new guidelines would increase the maximum limit to 350 parts per million. Air quality tests conducted earlier this year showed the plant averaging about 150 to 175 parts per million.