PETITION for review of order of Pollution Control Board.
MR. PRESIDING JUSTICE EGAN DELIVERED THE OPINION OF THE COURT:
Chicago Magnesium Casting Company ("Chicago Magnesium") appeals from certain portions of an order of the Illinois Pollution Control Board finding that Chicago Magnesium had violated section 9(a) of the Environmental Protection Act (Ill. Rev. Stat. 1971, ch. 111 1/2, § 1009 (a)) and imposing a $1000 fine. The case was submitted to the Board on an agreed statement of facts, which are summarized as follows:
Chicago Magnesium owns and operates a facility for the manufacture of castings, primarily of magnesium alloys. Among the manufacturing operations conducted is the pouring of molten magnesium alloys into molds. The manufacture of magnesium alloys often results in air-pollution emission problems during the pouring operations.
The standard operating practice in a sand foundry for magnesium-base alloys was to prepare the molten metal, to use sulphur dioxide gas or a dusting of sulphur powder at the pouring station and finally to protect the molten metal in the mold by sulphur admixed with the sand. These various agents can be a source of atmospheric pollution.
On July 6, 1970, Steven Rosenthal and Maxim Rice, engineers of the Illinois Environmental Protection Agency ("Agency"), investigated a complaint of odors in the vicinity of Chicago Magnesium. At that time Mrs. William Kempfer complained of a "sulphurous, burning and rotten odor that could make one nauseous." Donald Burnett, president of Chicago Magnesium, claimed that about 1% of sulphur is in the sand used in the molds and that some of the sulphur can escape into the atmosphere during the pouring process. Chicago Magnesium was aware of the odor problem and had been working with the Cook County Air Pollution Control Bureau in an effort to control the sulphuric emissions. Chicago Magnesium had conducted air-sampling studies in the vicinity of the plant and had attempted "odor masking" to abate the odors. Burnett told the engineers he had been cooperating with the owner of a nearby mobile-home trailer court through an agreement to shut down operations when the odors became objectionable at the trailer court.
On January 24, 1972, Rosenthal and Timothy Antonoplos of the Agency again visited Chicago Magnesium. Calvin Trock, superintendant of manufacturing operations, told them that sulphurous odors do occur and are emitted during pouring operations. At that time the Agency investigators detected a strong smoky odor approximately 100 yards downwind of Chicago Magnesium. They also observed a haze coming from the west exhaust fan drifting toward the trailer court which was approximately 400 feet to the north. They interviewed several residents of the nearby trailer court who complained of strong odors. Some of them testified by stipulation that they noticed a "rotten choking odor coming from Chicago Magnesium"; that "the odor made them cough and sneeze and their eyes burn when downwind of the company"; that "they noticed acid-like fumes and a choking odor coming from Chicago Magnesium"; that "the odor came when the wind was from the south and hurt their chests"; that "they noticed an awful sickening odor when the wind was from the south"; and that "the odor made them sick to their stomachs."
In June, 1972, Burnett attended a seminar which was addressed by Dr. J.B. Hanawalt, professor of metallurgical engineering at the University of Michigan. Hanawalt described his ongoing research into the use of sulphur hexafluoride to replace the use of sulphur as an inhibitor for molten magnesium. The paper he submitted at the seminar described the purpose of his study to be the elimination of the necessity for the sulphur agent in the sand. Later, Burnett personally discussed with Dr. Hanawalt the introduction of sulphur hexafluoride to replace sulphur in the production processes at Chicago Magnesium.
In July, 1972, Chicago Magnesium initiated the use of sulphur hexafluoride and abandoned the use of sulphur as an agent in its processes. In so doing, it became one of the first, if not the first, foundries in this country to use sulphur hexafluoride rather than sulphur as an agent. Since that date, Chicago Magnesium has not received any complaints from the owner or the residents of the nearby trailer court regarding odorous emissions. To introduce sulphur hexafluoride and replace sulphur as an agent has cost Chicago Magnesium approximately $3500.
Dr. Hanawalt had published two articles describing his research at the University of Michigan. The steps recommended by Dr. Hanawalt in the articles basically are those which have been implemented by Chicago Magnesium.
On December 1, 1972, the Agency filed a complaint against Chicago Magnesium alleging a violation of section 9(a). On February 6, 1973, Rosenthal again visited the Chicago Magnesium plant. He noted that sulphur emissions had been effectively abated. Upon inquiry, he received no complaints from the residents of the trailer court. In fact, they had no complaints as to the operations of Chicago Magnesium since July, 1972. Chicago Magnesium had begun filing the appropriate applications in order to obtain an operating permit for its facility in Blue Island. Those permit applications were presently being subjected to the Agency review procedures.
Donald Burnett testified by stipulation that before July, 1972, there was no economically reasonable nor technically feasible method for Chicago Magnesium to bring its emissions into compliance; and that prior to July, 1972, Chicago Magnesium had attempted to turn off its overhead exhaust fans in order to avoid spreading odors toward the trailer court when the wind was from a southerly direction.
Steven J. Rosenthal testified by stipulation that he had detected strong odors emanating from Chicago Magnesium during both his previous visits but that on February 6, 1973, the odors had been effectively abated; and that before utilization of sulphur hexafluoride there was no reasonable means for controlling sulphur dioxide emissions from magnesium foundries.
Chicago Magnesium affirmed its intention to continue the use of sulphur hexafluoride rather than sulphur. It stated that it would not abandon the use of sulphur hexafluoride nor reinstitute the use of sulphur as an agent without obtaining an appropriate operating permit from the Agency.
In its principal argument, Chicago Magnesium relies on section 33 of the Act (Ill. Rev. Stat. 1971, ch. 111 1/2, § ...