Pollution Paradox Is Solved

Ann Arbor's most paradoxical water polllution problem appears to be solved. Each April, Michigan's Water I Resources Commission (WRC) issues i appraisals of waste water control efforts i made during the previous year by the I state's industries. I Firms receiving the WRC's nighest I rating of "A" for 1970 include Gelman I Instrument Co. of 600 S. Wagner Rd., I Scio Township. I In this particular case, an "A" rating I might seem to be an almost routine I achievement. Gelman Instrument Co. is I a major manufacturer of filters for [ monitoring and controlling air and I water pollution. But as previously reported, Gelman's 1 carried the WRC's lowest rating of "E" during 1968 and 1969. The firm was, during those years, the f ■ ■ f 'only Ann Arbor industry with that distinction. The problem lay in two lagoons behind the Gelman plant which receive waterborne chemical wastes from the firm's unusual manufacturing processes. Specifically, the problem had two parts: overflow to the west toward Honey Creek, which drains into the Huron Biver; and unpleasant odors which at times penetrated some nearby homes and also reached the University's nearby Saginaw Forest. The WRC's "E" and "A" ratings related mainly to the overflow problem. In December, 1965 the WRC issued an order setting the legal limit for water use from Gelman's well at 9,000 gallons daily, adding that contents of the waste water are to be "not injurious to public health." In 1969, complaints from area dents concerning odor and overflow led I to tests by WRC officials for BOD count I (bio-oxygen demanding substances) in I the lagoons. This produced the "E" and I a declaration by a WRC regional official I that Gelman's lagoons contained "about I four times the amount of organic matter I in normal, untreated domestic sewage." A Gelman official told The. News in November 1969 that the firm was using I "about 20,000 gallons a day" and more on some days. A WRC permit to use 4 0,000 gallons daily was being sought by Gelman's at that time. Much has chaged since then. WRC officials told The News early ■ last year the lagoons had been deepened ■ and that overflow had stopped. Thomas Jameson, manager of chemical processing at the firm, said yesterday that more than deepening the lagoons is involved. Major modifications in the firm's ■ manufacturing processes have made it ■ possible to hold water use in line with 'm the WRC's 1965 order. The firm's appliI catión for a permit to use 40,000 gallons I daily has been withdrawn. The odor problem and high BOD count I have proven more complex to attack ■ than the overflow. Bacteria have not I been able to break down solvents in the ■ waste water as fast as the chemicals I accumulate. göJ An aerator placed several years ago I on the lagoon nearest the plant, where 1 ;■ chemical wastes flow initially, did not I inject enough oxygen to speed bacteria I growth significantly. That pond has I recently received a rubberized covering I to cut evaporation. The small aerator I remains. f Consulting service during the past I year by Prof. Jack A. Borchardt of the ■ U-M's civil engineering department has now led to an attack on the odor and ï BOD problem in the second of the I jl lagoons. This involves stepped-up I J oxygen injection by means of the I '[ ing aerators pictured above, in I ? tion with the addition of minerals to T speed bacteria growth. The aerators, ■ ? installed yesterday, are being rented but I 'j will be purchased if this combination of I ■ techniques solves the probem. 'i Jameson said yesterday about $4,000 I j to $5,000 in salaries can be attributed to I : [ work done on attacking the problems of I ij the lagoons.