Appeal from the Appellate Court for the First District; heard
in that court on a petition for review of an order of the
Pollution Control Board.
At issue in this consolidated appeal is the validity of revisions in State water-pollution regulations which govern levels of bacteria in what may be generally described as recreational waters. Drinking, or potable, water-quality standards are controlled by other regulations not before us.
The Illinois Environmental Protection Agency (the Agency) proposed the repeal of two water-quality standards governing maximum levels of bacteria in ambient waters (35 Ill. Adm. Code secs. 302.209, 302.406) and the amendment of the bacterial (liquid waste) effluent standard (35 Ill. Adm. Code sec. 304.121). Following the Agency's presentation of its proposal to the Illinois Pollution Control Board (the Board), the receipt by the Board of public comments and an economic impact statement as required by section 27 of the Environmental Protection Act (Ill. Rev. Stat. 1977, ch. 111 1/2, par. 1027), and a lengthy series of public hearings, the Board, with its chairman dissenting, adopted the Agency proposal. The Attorney General sought review of the Board's action in the appellate court pursuant to section 41 of the Environmental Protection Act (Ill. Rev. Stat. 1981, ch. 111 1/2, par. 1041), and that court reversed in part and affirmed in part (119 Ill. App.3d 561). We granted the Agency's petition for leave to appeal. 87 Ill.2d R. 315(a).
Only one of the two repealed water-quality standards, section 302.209, governing general-use waters, is involved in this appeal since the appellate court affirmed that part of the Board's order which adopted the Agency recommendation to repeal section 302.406, relating to certain other waters, and that affirmance has not been challenged here. Section 302.209 provided:
"Based on a minimum of five samples taken over not more than a 30-day period, fecal coliform * * * shall not exceed a geometric mean of 200 per 100 ml, nor shall more than 10% of the samples during any 30-day period, exceed 400 per 100 ml." (35 Ill. Adm. Code, sec. 302.209.)
Under the regulations this standard is intended to govern all general-use waters, which is the term used to describe all State waters except those which receive effluent from Chicago Metropolitan Sanitary District plants. (See 35 Ill. Adm. Code, sees. 302.201, 303.441.) Water-quality standards promulgated for general-use waters exist to protect "aquatic life, agricultural use, primary and secondary contact use and most industrial uses and [to] ensure the aesthetic quality of the State's aquatic environment." (Emphasis added.) (35 Ill. Adm. Code, sec. 302.202.) Primary contact is defined as "[a]ny recreational or other use in which there is prolonged and intimate contact with the water involving considerable risk of ingesting water in quantities sufficient to pose a significant health hazard, such as swimming and water skiing." 35 Ill. Adm. Code, sec. 301.355.
Before section 302.209 was repealed, fecal coliform (a type of mostly benign bacteria found in the feces of warm-blooded animals) were used, inter alia, to determine whether water was suitable for primary contact. Their presence in water has long been recognized by the scientific community as an indication of the presence of pathogens — organisms which cause disease, including such waterborne diseases as typhoid, dysentery, cholera, and gastroenteritis. That fecal coliform exist in a water sample does not establish with absolute certainty that pathogens are present, but indicates the probability of their existence. Even nonpathogenic species of fecal coliform may prove harmful since some strains have become drug-resistant and may transfer this quality to other pathogenic bacteria. The Agency found, and the Board agreed, that the fecal-coliform standard was an unreliable indicator and therefore not an appropriate measure of water quality, but neither the Agency proposal nor the Board's final rule contained a substitute microbiological indicator for waterborne pathogens. Thus, when section 302.209 was repealed, there existed no bacterial water-quality standard, although other standards, such as those governing radioactivity and chemical constituent maximums, remained in effect. See 35 Ill. Adm. Code, secs. 302.203 through 302.212.
The Board also approved the Agency's proposal to amend its bacterial-effluent standard, section 304.121 (35 Ill. Adm. Code, sec. 304.121). Prior to amendment, this standard prohibited all treatment plants from discharging effluent which exceeded 400 fecal coliform per 100 milliliters. The regulation, as amended, provided:
"No person shall cause or allow fecal coliform * * * to exceed 400 per 100 ml in any effluent which discharges to the following locations:
(a) During the months of May through September, within 20 stream miles (statute miles) upstream of a public bathing beach licensed under the `Illinois Swimming Pool and Bathing Beach Act' (Ill. Rev. Stat. 1979, ch. 111 1/2, pars. 1201-1227).
(b) Within 20 stream miles (statute miles) upstream of a water intake used for public or food processing water supply.
(c) Any location where it may cause or contribute to violation of another state's water quality standards in interstate waters." (35 Ill. Adm. Code, sec. 304.121.)
It is clear from the record before us that the principal motive prompting the amended regulatory scheme was the termination or minimization of the expensive discharge-chlorinating process used to treat sewage and waste water wherever such termination or reduction could be accomplished without jeopardizing the public health. The chlorination process itself, although used by 90% of Illinois treatment plants, is not without potential health risks, and it probably does not kill all pathogenic material. The amended standards are designed to obviate the need for continued chlorination by substituting 20-mile buffer zones affording protection to recreational users at licensed beaches, to potable and food-processing water supplies, and for interstate waters. Our review is, of course, limited to the validity of the means chosen to effect this policy change.
As has been previously stated, the appellate court affirmed the Board's decision to repeal one of the water-quality standards, former section 302.406 (35 Ill. Adm. Code, sec. 302.406), which contained a fecal-coliform criterion for secondary-contact waters (see 35 Ill. Adm. Code, sec. 301.380). The court reversed the repeal of section 302.209 on the grounds that the Board exceeded its statutory authority in deleting this regulation without replacing it with another microbiological indicator of pathogens. In striking the amended effluent standard, the court held ...