PUBLIC HEALTH ASSESSMENT
OSSINEKE, ALPENA COUNTY, MICHIGAN
The Ossineke Ground-water Contamination site is listed on the U.S. Environmental Protection Agency (U.S. EPA) National Priorities List (NPL). The site, located in Ossineke, Michigan, was identified in 1977 after nearby residents reported a gasoline odor in their well water. A plume of contamination including benzene, toluene, xylenes, and other gasoline components has been found in the groundwater, and is attributed to spills from a gas station and possibly to leaking underground storage tanks. A nearby laundromat, which has reported spills and leaks of tetrachloroethylene, could also be a source of groundwater, surface water, and soil contamination.
Suspect underground tanks have been removed. All known contaminated residential wells have been replaced with wells that draw on a deeper, uncontaminated aquifer. The U.S. EPA has decided that the Michigan Department of Natural Resources should be the lead agency for remediation of the contamination attributed to the laundromat and that the U.S. EPA's Office of Underground Storage Tanks should direct the remediation of the rest of the site.
The contamination in the groundwater did pose a public health hazard in the past and could potentially in the future if the groundwater was used for potable purposes. All wells that are known to have used the contaminated aquifer in or near the contaminant plume have been replaced. Presently, the site poses no apparent public health hazard under current conditions. A new well drilled into the shallow aquifer, in spite of advice from the local health department, the state health code, and public awareness of the contamination, could be contaminated. Older contaminated wells that have been replaced but not properly abandoned might be brought back into use. Appropriate actions to more effectively prevent wells from being drilled into the contaminated aquifer should be implemented, wells that have been replaced should be properly abandoned, and existing residential wells that might be endangered by the contamination should be monitored.
Residents of the site area reported gasoline odors in their basements in April 1982. This has been attributed to a gasoline spill at a gasoline station in the site area the previous winter and the odors have not recurred. In 1990, various volatile organic chemicals were identified in the air in basements on and near the site. Though the concentrations were generally not high enough to cause non-cancer adverse health effects, the levels found of benzene, carbon tetrachloride, chloroform, methylene chloride, tetrachloroethylene, trichloroethylene, and styrene (all confirmed or potential carcinogens) could pose a significantly increased cancer risk. The locations of the basements where these chemicals were detected indicate that there could be sources for these chemicals other than the environmental contamination at the site, including chemicals used by the residents in their household activities.
The Ossineke Ground-water Contamination site was listed on the U.S. Environmental Protection Agency (U.S. EPA) National Priorities List (NPL) on December 30, 1982. The site is located in the town of Ossineke, Sanborn Township, Alpena County, Michigan. The site (Figure 1) includes two primary areas of concern: "Area 1," which straddles U.S. Highway 23 just north of Nicholson Hill Road and south of LaRose Street, between Old Ossineke Road on the west and Alphonse Street on the east; and "Area 2," a laundry/dry cleaning facility and associated washwater pond located approximately 1/3 mile north of Nicholson Hill Road along U.S. 23. The site consists of several small properties owned by private citizens.
The site area is a small commercial district along U.S. 23 north of Nicholson Hill Road with surrounding and interspersed residences. The businesses include a building supply and lumber yard, a gasoline station, an auto parts store, an auto repair shop, a post office, a bank, two grocery stores (one of which also sells gasoline), a beauty parlor, a laundry/dry cleaning (laundromat) facility, two restaurants, and a pharmacy. Historically there have been gasoline stations on the northwest corner of the intersection of U.S. 23 and Nicholson Hill Road, and one of the restaurants at one time also sold gasoline.
Before 1973, an auto rustproofing operation occupied a lot near the corner of U.S. 23 and Nicholson Hill Road that is currently the site of a Marathon gasoline station. When the rustproofing business ceased operation, workers cleaned the garage floor with a chlorinated hydrocarbon solvent and disposed of the spent solvent onto the ground behind the main building.
In 1977, several residential wells in Ossineke were found to be contaminated with benzene, toluene, xylene, phenol, and tetrachloroethylene. Possible sources for this contamination included gasoline spills and leaking underground gas storage tanks located at three businesses near the intersection of U.S. 23 and Nicholson Hill Road: KC's Country Kitchen restaurant (now called The Barn), the Marathon station, and Ossineke Building Supply. The tanks at the restaurant and the building supply store have been removed.
A lagoon located in Area 2 was used for waste disposal by a commercial laundromat, and is also considered a potential source for groundwater contamination. Leaks or spills of tetrachloroethylene from the laundromat's operation were reported in 1978 and 1980 (1).
When they were notified that the groundwater was contaminated, property owners with contaminated wells either had deeper wells drilled or had their plumbing connected to a neighbor's uncontaminated well. Some started using bottled water for drinking and cooking. In 1983, water sampling by the Michigan Department of Public Health (MDPH) revealed that one replacement well, that had been drilled in the shallow aquifer, was contaminated. The remainder of the replacement wells were drawing from the uncontaminated lower aquifer. In 1984, the Michigan Department of Natural Resources (MDNR), under provisions of the Michigan Environmental Response Act (Act 307), allocated funds to provide alternate water supplies for those property owners who had not yet replaced their wells.
In April 1982, members of the community complained to the Michigan State Police of gasoline odors in their basements. During the subsequent investigation, one resident recalled that a snow plow had accidentally knocked over one of the gas pumps at the Marathon gasoline station during the previous winter. An unknown amount of gasoline had been released into the ground. The Michigan State Police and the Sanborn Township Fire Department attributed the basement odors to the pump spillage incident. In December 1982, the U.S. EPA placed the Ossineke Ground-water Contamination site on the NPL.
A secondary problem developed with some of the newly constructed wells in the deeper aquifer. Because of artesian conditions in the aquifer, groundwater discharge rates of up to 81,000 gallons per day resulted in the flooding of residential yards. In June 1986, the MDPH received State funds to eliminate the flooding problem. Additional funds were requested by MDPH in July 1986 to replace 2 other contaminated private wells.
On March 10, 1989, working under a cooperative agreement with the Agency for Toxic Substances and Disease Registry (ATSDR), MDPH prepared a Preliminary Health Assessment for the Ossineke Ground-water Site. The Preliminary Health Assessment concluded that the site was of potential human health concern because of the presence of various volatile organic chemicals in the groundwater. The assessment concurred with the sampling plans for the Remedial Investigation and Feasibility Study (RI/FS), with a specific recommendation that the RI include analysis for tetraethyl lead and polynuclear aromatic hydrocarbons. The preliminary health assessment did not recommend any follow-up health studies (2).
Field work for the RI/FS of the site was carried out between May 1989 and March 1990, and the RI report was issued in January 1991 (3).
On June 28, 1991, the U.S. EPA signed a Record of Decision for the site stating that remediation of the site would be transferred out of the Superfund program. The Area 1 contamination, consisting primarily of gasoline components, falls under the petroleum spill exclusion in Section 101 of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980, as amended. Such cases fall under the jurisdiction of the U.S. EPA's Office of Underground Storage Tanks, which would direct further remediation through the MDNR (4). Area 2, the laundromat and lagoon area, does not meet U.S. EPA standards for inclusion on the NPL, based on a 1988 evaluation (1). The MDNR has agreed to remediate Area 2 under provisions of Michigan's Act 307 (5). As of early 1993, two underground storage tanks have been removed from The Barn restaurant's property.
There are wetlands to the east and northwest of the site. The closest wetland area is 200 feet east of the washwater pond. The South Branch of the Devil's River is approximately 0.25 mile west of the site. The South Branch flows northward to approximately 1 mile north of the site, then turns northeastward to join the North Branch and form the Main Branch of the river. The Main Branch flows northeastward into Thunder Bay on Lake Huron, approximately 2 miles northeast of the site.
The subsurface soil in the site area is mainly sand and gravel. A continuous clay bed is found at 15 to 30 feet below ground level, depending on the location. This clay bed is at least 40 to 45 feet thick, and may be thicker in places, with sand lenses possibly interbedded within it. There is another sand bed, of unknown thickness and extent, beneath the clay layer. Shale bedrock, part of the Antrim Formation, was found at 168 feet below the surface in one area well.
The water table varies between 2 and 15 feet below the ground surface in the site area, in an unconfined aquifer above the clay bed. The washwater pond, the neighboring wetlands, and the South Branch of the Devil's River may be hydraulically connected with the groundwater. Groundwater flow is to the north-northeast. There is a deeper aquifer of uncertain extent in the sand beneath the clay bed, which has shown artesian or upward pressures when wells were drilled into it. There is no record of whether the bedrock at the site contains any aquifers.
The MDPH started preparation of this public health assessment in early 1991. As mentioned above, since then the U.S. EPA has issued a Record of Decision to remove the site from the NPL, transferring responsibility for the two sections of the site to the U.S. EPA's Office of Underground Storage Tanks and the MDNR. Two underground tanks that were suspected of leaking have been removed from the site area.
Brendan Boyle, Laura Brabec, and Linda Swain of MDPH visited the site with staff from District Health Department #4 in July 1988. Information and observations collected on this visit are included in the relevant sections of this assessment. On April 24, 1991, James Bedford and John Filpus of MDPH visited Ossineke to attend a public meeting called by the U.S. EPA to present their plans to remove the site from the NPL. Before the meeting, Bedford and Filpus drove through the site area, observing the distribution of residences and businesses around the site. The lagoon behind the laundromat was not visible from the road. Local health department personnel say that the site area was essentially unchanged between that visit and August 1995 (6).
The site area includes approximately a dozen residences. The closest residence to the suspected spill area at the Marathon gas station is less than 200 feet away. The nearest residence to the laundromat's lagoon is approximately 200 feet to the south.
Preliminary 1990 U.S. Census data report that Sanborn Township had a population of 2,196. Approximately 34 per cent of the population is under 18, 9 per cent under 5, and 11 percent over 65. The population of Alpena County as a whole, from the 1990 Census, is 98.7% non-Hispanic white, 0.5% Hispanic, 0.3% Native American, 0.3% Asian or Pacific Islander, 0.1% African-American, and 0.1% other race. The major ethnic groups represented in the county include Polish, French, German, and Irish.
There is a county park and a State Forest campground at the mouth of the Devil's River, 2 miles northeast of the site. An elementary school is located approximately 0.25 mile southwest of the site.
Development in the Ossineke area is mainly along the major roads. The rest of the area is undeveloped woodland and wetlands. There is some concentrated development for approximately 0.25 mile in all directions from the intersection of U.S. 23 and Nicholson Hill Road. There is a mixture of commercial establishments and residences along the major roads, with residences on the side streets. The immediate vicinity of the intersection of U.S. 23 and Nicholson Hill Road is zoned for commercial use. The area to the northeast, along Alphonse and Larose Streets, is zoned for residential uses. Ossineke residents use private wells and septic systems, because there is no community water supply or sewer service available.
Undeveloped land in the area is used for recreation, including hunting, camping, hiking, cross-country skiing, and snowmobiling. There is also boating, swimming, canoeing, and fishing on Lake Huron and the Devil's River. Short term residents and tourists, especially during the summer and the fall deer-hunting season, may temporarily increase the population of the region.
In response to community concerns, the assessors have obtained data on cancer mortality from State mortality records; and on cancer incidence from the Michigan Cancer Registry which has been in existence since 1986. Specifically, we requested age-adjusted incidence rates for the years 1986-91, and age-adjusted mortality rates for the years 1980-91, with comparison to state rates.
Area residents have expressed concern about potential health effects that could result from drinking contaminated water. Some residents of the area wrote several letters to various governmental authorities when they noticed the contamination in their well water. The complaints mainly concerned the gasoline odor in the water. A gasoline odor was also detected in some basements near the site in 1982. These odors have been attributed to the gasoline pump accident mentioned above. Basement odors have not recurred since that incident.
In April 1991, the U.S. EPA called a public meeting in Ossineke to announce the proposed delisting of the site from the NPL. At the meeting, which James Bedford and John Filpus of MDPH attended, two Ossineke residents expressed the following concerns about cancer in the area:
1. There appears to be a large number of relatively young persons in the neighborhood who have had cancer. Could the contamination be responsible?
2. I have had cancer. Could drinking the contaminated water have had any effect on my current health condition?
These health concerns are addressed later in the Public Health Implications section.
The MDPH released a draft of this Public Health Assessment for public comment on December 14, 1994. The comment period lasted until January 13, 1995. The MDPH received no comments in this period.