A History of the Gas Plant at Broadway
1899: Ann Arbor Gas Company constructed a gas works on the property
1914: Operations turned over to Washtenaw Gas Company
1915: Washtenaw Gas and Eastern Michigan Edison negotiated relocation of the Huron River Channel
1918: Commission on the Revision of rates of the Washtenaw Gas Company was formed The Commission devised a plan of sliding rates for Ann Arbor. A unique feature of the plan was that it combined retroactive profit-sharing with the sliding rates.
1937: The Washtenaw Gas Company filed an application with the Michigan Public Utilities Commission The company wanted permission to build a 21 mile pipeline to use Texas gas in Ann Arbor. However, there was bitter controversy over the use of Texas gas. The Michigan natural gas producers were convinced that Washtenaw Gas Company was trying to push them out of business; that the natural gas market in Michigan rightfully belonged to Michigan producers. The Washtenaw Gas Company countered that Michigan natural gas was insufficient and would cost more. According to calculations, the Washtenaw Gas Company was correct; the Michigan reserve of natural gas would have been depleted in 10 years and it also would have cost the citizens more.
1938: (September) Washtenaw Gas Company was dissolved and its property was acquired by the Michigan Consolidated Gas Company
1939: A pipeline was constructed introducing Texas gas to the distribution system
1940s: Michcon ended operation of the gas plant (The plant had been kept running as a back-up in the first years of natural gas use.)
1955: Gasification plant was dismantled
1984: Department of Environmental Quality requested a site investigation
1984-1985: EDI Engineering & Sicence conducted an initial site investigation
1993: W.W. Engineering and Science collected additional subsurface data while investigating an underground storage tank
1996: Flouor Daniel GTI (1997) conducted a Remedial Investigation of the Broadway Street site 2000: ThermoRetec Consulting Corporation conducted an Exposure Pathway Evaluation
Coal gasification
“Coal gas is manufactured by heating coal in large brick ovens to the point of vaporization. The vaporized portion is collected and sent through various processes to remove impurities. Coal tars are removed through condensation. Scrubbers may be employed to remove naphthalene, sulfur compounds, carbon dioxide, hydrogen cyanide, and ammonia…The unvaporized portion remaining in the ovens contain coke which can be burned to provide some of the heat for the process. “The gasification combustion process leaves residues of heavy metals, cyanide (from pyrolitic reactions), volatile organics, and various polynuclear aromatics (PNAs).” --DEQ Site Description/Executive Summary, 1986.
According to an investigation conducted in 1985, subsurface soils around the old plant site were contaminated with inorganics and heavy metals, and volatile organics. Surface soils contain lower concentrations of the same contaminants. Groundwater was also contaminated with gasification by-products, including lead, nickel, mercury, zinc, arsenic, and cyanide, all above safe drinking water standards. Inorganics, organics, and polynuclear aromatics were also high.
It was reported in 1998 to the DEQ that 1,680 cubic yards of tar-stained soil and debris were removed and disposed of as non-hazardous waste.