Last year 129 million pounds of chemicals were released into the air by companies operating along the Wasatch Front - an increase of 8 million pounds.

The toxic brew included such ingredients as chlorine, benzene, lead, nickel and arsenic compounds. Some of the released substances are known carcinogens, others are considered "possible" or "probable" carcinogens.The single largest contributor of air toxics was Magnesium Corp. of America (Magcorp) in Tooele County, which released more than 119 million pounds of chemicals, including 34 million pounds of chlorine. Magcorp's emissions increased by 9 million pounds from 1988, according to the Utah Toxic Release Inventory Summary Report.

The report noted that Hercules, which is a large source of air toxics and is located near a highly populated area, released substantial amounts of dichloromethane, a carcinogen.

The amount of emissions is based on toxic release inventory reports companies submitted to the state under the provisions of the Emergency Planning and Community Right-To-Know Act of 1986. The reports are used to assess public health or environmental risks, compliance with permit programs and to compare similar industry emissions in the state.

In 1989, 97 facilities submitted reports on air toxics. Only 10 of the state's 29 counties have industries large enough to qualify as reporting sources. Ninety-two percent of the emissions of toxic air pollutants occurred in Tooele County, which contains only 2 percent of the state's population.

Because companies are not required to report the rate of release for the chemicals, there is no way of knowing if the release occurred evenly over an entire year or over a few brief periods.

The total emissions figure is also undoubtedly an underestimation of air toxic releases because only a portion of facilities emitting or transferring toxic chemicals are required by law to submit reports, according to the Utah Division of Environmental Health.

Also, companies are only required to file reports on the 300 chemicals listed as toxic by the federal government; releases of hundreds of other chemicals go unreported.

In addition, only 16 percent of the 1989 emission figures were based on actual monitoring data, according to company reports. That means most of the emissions data was based on engineering estimates or other calculations.



The top 20 - in air releases of toxics

The 20 companies that released largest amounts of air toxics in 1989 are:

Pounds released

1. Magnesium Corp. of America, Tooele County 119,060,170

2. Hercules Inc. Bacchus Works,* Salt Lake County 2,720,500

3. Thiokol Corp., Box Elder County 2,041,500

4. Thiokol Corp., Davis County 574,000

5. Kennecott Copper Division, Salt Lake County 553,800

6. Nucor Steel, Box Elder County 498,400

7. Unisys, Salt Lake County 374,250

8. LaRoche Industries Inc., Utah County 296,201

9. Olympia Sales Company, Salt Lake County 284,148

10. Varian EIMAC, Salt Lake County 205,300

11. Hercules Inc. Bacchus Works,* Salt Lake County 190,965

12. Litton Guidance & Control Div., Salt Lake County 183,400

13. Utility Trailer Inc., Davis County 156,880

14. Deseret Medical Inc., Salt Lake County 149,456

15. Amoco Oil Company, Salt Lake County 146,246

16 Fashion Cabinet Manufacturing Inc., Salt Lake County 142,600

17. Trojan Corp., Utah County 140,000

18. Companion Systems Inc., Salt Lake County 125,728

19. National Semiconductor, Salt Lake County 117,588

20. Chevron U.S. Inc., Salt Lake County 111,650