PUBLIC HEALTH ASSESSMENT
REILLY TAR & CHEMICAL CORPORATION SITE
ST. LOUIS PARK, HENNEPIN COUNTY, MINNESOTA
The Reilly Tar and Chemical Corporation Site (Site) is listed on the U.S. EnvironmentalProtection Agency's (EPA) National Priorities List. The Site is located in the city of St. LouisPark, in eastern Hennepin County, Minnesota.
From 1917 until 1972, the Reilly Tar and Chemical Corporation (now known as ReillyIndustries, Inc.; Reilly) operated a coal tar distillation and wood preserving plant, known as theRepublic Creosote Company, on the Site. The spilling of coal tar and creosote on-Site, and thedischarge of contaminated wastewater off-Site during plant operations resulted in thecontamination of soil and area aquifers with polycyclic aromatic hydrocarbons (PAHs) andphenolic compounds.
Contamination of local wells with Site-related chemicals was first documented in the 1930's. Throughout subsequent years, there were numerous reports of contaminated wells and complaintsfrom the local community about odors and soil and surface water contamination. In 1978, theMinnesota Department of Health closed six municipal wells in St. Louis Park and one well inneighboring city of Hopkins because of contamination with PAHs. These compounds are foundin relatively high concentration in both coal tar and creosote.
In 1972, the city of St. Louis Park purchased the Site from Reilly and the plant facility wasdismantled. A major portion of the Site is currently used as a park. There are also threeapartment complexes, light industries, and small business located on-Site. The areas surroundingthe Site on the west, north, and east are primarily composed of single-family residences; there isprimarily light industry to the south of the Site.
Local residents use municipal water drawn from aquifers contaminated with low levels of PAHs. Exposure to these compounds may occur via ingestion of and dermal contact with potable water. However, concentrations of PAHs in the water from several municipal wells are closelymonitored to assure that they are below Drinking Water Criteria. These Drinking Water Criteriawere derived through a joint effort between the MDH, MPCA, and EPA, and are defined as therecommended maximum permissible concentrations of PAHs in drinking water which providefor the protection of human health. Finished water supplies (that is, water obtained at the tap) arenot monitored for PAHs.
In a 1979 epidemiological study, MDH found a statistically significant increase in the incidenceof breast cancer in St. Louis Park females (cancer data from the Third National Cancer Surveyfor the years 1969 to 1971 were analyzed). In a 1985 report to the Minnesota Legislature entitled"Feasibility of Community-Wide Epidemiologic Studies of Drinking Water and Health: St. LouisPark & New Brighton", the MDH concluded that it was unlikely that the observed excess ofbreast cancers in St. Louis Park could be related to [ingestion of] water contaminants.
A potential route of human exposure to Site-related chemical contaminants currently existsbecause gullying and erosion of the hill on the southwestern portion of the Site may be exposingpreviously inaccessible, contaminated soil. This hill was formed when visibly contaminated soiland demolition debris were excavated/moved from other parts of the Site following thedismantling of the plant buildings and the construction of on-Site housing units.
The final agreement for the remediation of the Site is outlined in the 1986 Consent Decree-Remedial Action Plan. Many provisions of this document are completed, and others arecurrently being carried-out.
MDH will follow the progress of investigations and clean-up activities at the Site. MDH will, atthe request of the appropriate parties (for example, the MPCA), review reports or progressupdates prepared by those carrying out clean-up activities.
The data and information developed in this public health assessment have been evaluated by theAgency for Toxic Substances and Disease Registry (ATSDR) Health Activities RecommendationPanel for follow-up health actions. Although human exposure to site contaminants is currentlyoccurring via drinking water use, this exposure is not occurring at levels of public health concern. A community health education effort related to this site has been undertaken. This site is notbeing considered for additional follow-up health activities at this time. However, if data becomeavailable suggesting that human exposure to hazardous substances at levels of public healthconcern is occurring, ATSDR and MDH will re-evaluate this site for any additional follow-uphealth activities.
Based on the information and data reviewed, the MDH concludes that the Reilly Tar andChemical Corporation site poses no apparent public health hazard.
The Reilly Tar and Chemical Corporation Site (Site) is listed on the U.S. EPA's NationalPriorities List. The Site is located in the city of St. Louis Park (City), in eastern HennepinCounty, Minnesota (Figure 1). The boundaries of the 80-acre Site are as defined in the RemedialAction Plan program of the 1986 Consent Decree (1). The approximate location of the Site iswest of Gorham and Republic Avenues, south of 32nd Street, east of Pennsylvania Avenue, andnorth of Walker Street (Figure 2).
From 1917 to 1972, the Reilly Tar and Chemical Corporation (now known as Reilly Industries,Inc.; Reilly) operated a coal tar distillation and wood preserving plant, known as the RepublicCreosote Company, on the Site. Plant operations consisted of the high temperature distillation ofcoal tar to produce creosote, which was subsequently used as a wood preservative. The bulk ofthe plant's operations took place in the south-central and southeastern portions of the Site. It wasin these areas that the coal tar distillation still, wood-treating building, and above ground andunderground storage tanks (for creosote, tars, pitch, and fuel oils) were located. From 1917 to1939, raw waste water containing coal tar and creosote was discharged into a drainage ditch thatoriginated in the northern portion of the Site and ran the length of the Site (approximate path wasNE to SW). Historical aerial photographs show the northern portion of the Site possiblycontained a waste disposal area. Once off-Site, the drainage ditch connected with a series ofother ditches which eventually emptied into a small marsh approximately 600-700 feet south ofthe Site. In 1940/1941, Reilly installed a waste water treatment plant, but continued to dischargethe effluent off-Site until operations ceased in 1972. Typical concentrations of phenoliccompounds and oil and/or grease in this wastewater varied between 100 and 1,000 mg/L. Theeffluent that collected in the marsh eventually discharged to the Minnehaha Creek approximately2,250 feet south of the Site. Chemical contaminants may have also been released from a wastepond located in the main coal tar distilling/wood preserving area in the SE corner of the Site. Soil contamination with coal tar and creosote occurred in this, and other portions of the Site, viadrips from leaky piping, precipitation wash-off from stockpiled treated lumber, and spills ofprocess materials throughout the operational history of the Republic Creosote Company.
In addition to contaminating soil and surface water, the release of coal tar and creosote from theSite resulted in the contamination of the area's groundwater. The contamination of area aquifersmay have occurred by one or more of the following processes: 1) the direct downwardinfiltration of chemicals through the soil from waste pond(s) and the marsh, 2) via multi-aquifer wells in the area of the Site, 3) direct injection or overflow of wastes into on-Site well(s),and 4) via a buried bedrockvalley southeast of the Site which connects the Drift-Platteville aquifer with the St. Peter aquifer(see below).
The Site overlies six regional aquifers. A brief introduction to these aquifers (starting at groundlevel) is presented below:
- The Surficial Drift Aquifer - This is the first aquifer encountered under the Site. It isapproximately 50 feet thick; groundwater in it flows to the east-southeast.
The Platteville Aquifer - This is the first bedrock aquifer encountered under the Site. It ishydrologically connected to the surficial Drift. Because of this connection, the surficial Drift andPlatteville aquifers are often considered as one aquifer (Drift-Platteville). Groundwater flow inthis aquifer is toward the east.
The St. Peter Aquifer - This aquifer is separated from the Drift-Platteville by the thin Glenwoodconfining bed. Groundwater movement in this aquifer is toward the southeast.
The Prairie du Chien-Jordan Aquifer - This aquifer is separated from the St.Peter by the BasalSt. Peter confining layer. The Prairie du Chien-Jordan is the region's major groundwater resource. Approximately 75-80% of groundwater withdrawals in the St. Louis Park and Minneapolis-St.Paul Metropolitan areas are from this aquifer. Groundwater in this aquifer moves in an east-southeast direction, but can be significantly affected by pumping stresses from municipal andindustrial wells in the region.
The Ironton-Galesville Aquifer - This aquifer is not highly productive and is not utilized in thearea.
The Mt. Simon-Hinckley Aquifer - This aquifer is separated from the Ironton-Galesville by theEau Claire confining bed. The Mt. Simon-Hinckley is the deepest (800-900 feet below thesurface) productive aquifer in the Minneapolis-St. Paul Metropolitan area.
On-Site and off-Site groundwater and soil contamination with coal tar and creosote has beendocumented since the early 1930's (2-5). Both coal tar and creosote are complex mixtures oforganic compounds. The major constituents of coal tar are phenolic compounds (phenolics) suchas phenol, cresols, and methylphenols, and polycyclic aromatic hydrocarbons (PAHs). Creosoteis composed primarily of PAHs (75-80%) such as naphthalene, phenanthrene, fluoranthene,acenaphthene, fluorene, and pyrene, but phenolic compounds such as phenol, cresols, andmethylphenols are also present (2-17%). The following is a brief chronology of chemicalcontamination of the Site and surrounding area:
|1)||In 1932, the City drilled it's first municipal well approximately one-half mile east of the Sitein the Prairie du Chien-Jordan aquifer. The well had to be closed within weeks of start-upbecause the water had a coal tar taste and odor problems.|
|2)||In 1933, another Prairie du Chien-Jordan well one mile east of the Site was found to becontaminated with a coal tar taste.|
|3)||In 1938, the Minnesota Department of Health documented both the discharge ofcontaminated waste water to ponds south of the Site and the contamination of wells near the Sitewith phenolic compounds.|
|4)||During the 1930's and 1940's, several private wells finished in the Drift-Platteville exhibitedcontamination.|
|5)||Complaints from nearby residents regarding the contamination of shallow wells becamecommon in the late 1940's into the 1950's.|
|6)||In 1958, a large plug of coal tar of unknown origin was discovered in an on-Site water supplywell. This coal tar plug directly contaminated the Prairie du Chien-Jordan and Ironton-Galesvilleaquifers.|
|7)||Sampling conducted during the 1970's and in 1988 confirmed that on-Site and off-Sitesubsurface soils were contaminated with PAHs, phenolics, and unidentified organic contaminantsreferred to as benzene-extractables.|
|8)||Wells in St. Louis Park were first sampled for PAHs 1978. At that time, several wells wereshown to have low, but detectable levels of carcinogenic and non-carcinogenic PAHs. However,four Prairie du Chien-Jordan municipal wells (SLP 10,15,7, and 9) had obviously higher levels ofPAHs. Carcinogenic PAHs (benzo[a]pyrene, benzo[ghi]perylene, and indeno[1,2,3-cd]pyrene)were detected in SLP 10 and 15 at concentrations of less than 10 ng/L; none were detected inSLP 7 and 9. Non-carcinogenic PAHs (anthracene, pyrene, fluoranthene, and naphthalene) weredetected in the four wells at concentrations ranging from 10-1000 ng/L. In subsequent years,these PAHs, as well as other carcinogenic and non-carcinogenic PAHs, were being consistentlydetected in other Prairie du Chien-Jordan municipal wells. Between 1978 and 1981, the MDHclosed six Prairie du Chien-Jordan municipal wells in St. Louis Park (SLP 4,5,7,9,10,and 15) andone in neighboring city of Hopkins (Hopkins 3) because of PAH contamination.|
Because of continuing problems with odors, and soil and surface water contamination, the Cityand the MPCA filed a lawsuit against Reilly in October, 1970. In April, 1972, the Citypurchased the Site from Reilly and, as a condition of the sale, dropped its lawsuit against Reilly. In June, 1973, the City deeded the Site to the St. Louis Park Housing and RedevelopmentAuthority which subsequently sold portions of the Site to three private parties. The MPCAamended it's original lawsuit against Reilly in April, 1978 alleging that Reilly's coal tar andcreosote wastes contaminated the area's groundwater with PAHs, and that further migration ofPAHs threatened aquifers used for public water supplies. To compel Reilly to undertakenecessary remedial actions, further legal and administrative actions were taken by federal andstate agencies during 1978 - 1985. The final agreement for the remediation of the Site wasreached in 1985 and is contained in the Remedial Action Plan (RAP) portion of the September1986 Consent Decree-Remedial Action Plan (CD-RAP) (1). The objectives of the RAP are to: 1) provide a safe drinking water supply in sufficient quantity for the City and surroundingcommunities, 2) control the spread of contamination in the regional aquifers, 3) allow for safe,reasonable, and beneficial use of the Site and adjacent contaminated areas, and 4) preserve andprotect groundwater resources for present and future uses. The fulfillment of the RAP portion ofthe CD-RAP will constitute the full settlement of all pending claims against Reilly Tar andChemical Corporation.
Much of the Site is currently designated as, and is used as a park. The majority of the Site isrelatively flat and vegetated with grass. Three rental condominium and/or apartment complexesare located in the northern and central portions of the Site. There are commercial properties andlight industrial facilities on the eastern edge of the Site. There are primarily private and multi-family residences bordering the Site to the west, north and east, and light industries to the south.
Because of the complexity of the on- and off-Site groundwater and surficial contamination andproposed response actions, the RAP divided the remediation of the Site into functionalcomponents called "operable units." This Public Health Assessment for the Reilly site willdiscuss the contamination, as well as any completed, on-going or proposed remedial actions interms of these operable units. The three operable units (and their components) are:
- 1) Aquifers Beneath the Site -
- a) Drift and Platteville (Drift-Platteville)
b) St. Peter
c) Prairie du Chien-Jordan
e) Mt. Simon-Hinckley
- 2) Multi-Aquifer Wells (Leaking Multi-Aquifer Wells) -
- a) Wells Open to the Mt. Simon-Hinckley, Ironton-Galesville, or Prairie du Chien-JordanAquifers
b) Wells Open to the St. Peter Aquifer
- 3) Near-Surface Contamination -
- a) Soil Investigation
b) Wetlands Filling
A number of remedial activities for the operable units were specified in the RAP. In addition,remedial activities were also performed at the Site prior to the institution of the RAP. The majorremedial activities which have either been completed or are currently in progress are discussedbelow:
- Operable Unit: Aquifers
- Drift-Platteville Aquifer
An off-Site Drift aquifer contaminant source control well (W420) and a Platteville contaminantsource control well (W421) were installed in October, 1987. Both wells are south of the Site. Between 1988 and 1991, discharged groundwater was routed to the sanitary sewer system fortreatment at the Metropolitan Waste Control Commission (MWCC) wastewater treatment plant. The construction of a granular activated carbon (GAC) treatment system for removing organiccontaminants from the discharge water was completed in late 1990. GAC-treatment ofgroundwater with discharge to Minnehaha Creek began in June, 1991 and will continue for aminimum of five years, at which time a direct discharge will be considered by the MPCA,providing the discharge meets surface water discharge limits.
An off-Site contaminant gradient control well (W422) was installed in October, 1987. This wellcurrently discharges groundwater to the sanitary sewer for treatment at the MWCC plant.
The City of St. Louis Park completed a Remedial Investigation (RI) for the area directly east ofthe Site (referred to as the Northern Area) in June, 1989. A supplemental RI and the FeasibilityStudy (FS) outlining potential remedial actions for the Northern Area was submitted by the Cityin July, 1991. The MPCA proposed a cleanup plan for the Drift Aquifer (Northern Area) inAugust, 1992. The plan is to continue using W422 but to augment it with one or more additionalpumping wells. A cleanup plan for the Platteville Aquifer will also be made by MPCA.
Starting in 1991, 20 Drift-Platteville monitoring wells will be sampled twice yearly. The CD-RAP allows for additional source and/or gradient control wells or the modification of thesewell(s) contingent on sampling results.
- St. Peter Aquifer
The City of St. Louis Park submitted a final RI report for the St. Peter aquifer in September,1989. As part of the associated FS, well number W410 was recompleted and evaluated for it'sability to control the spread of the contaminant plume in the aquifer. A ROD was signed by EPAand MPCA in September, 1990. Under the ROD, W410 is to be pumped to intercept and containthe contaminant plume. W410 is now operational with groundwater discharge routed to thesanitary sewer for treatment at the MWCC wastewater treatment plant. The MPCA anticipatesthat, within three to five years, the quality of the groundwater pumped from W410 will haveimproved sufficiently to meet National Pollutant Discharge Elimination System (NPDES) limitsand thus can be discharged to Minnehaha Creek.
The continued monitoring of this aquifer's water level and water quality (for example, PAHconcentration) is also a requirement of the ROD. If water quality does not improve over the threeto five year pumping period, and the City intends to discharge to Minnehaha Creek, an on-Sitetreatment facility will be built to ensure that the discharged groundwater meets NPDES limits.
- Prairie du Chien-Jordan Aquifer
On-Site well W23, which was contaminated with coal tar, was cleaned-out in 1981 under aCooperative Agreement between EPA and MPCA.
An EPA ROD for the installation of a GAC treatment system for St. Louis Park Municipal wells10 and 15 was signed in June, 1984. These municipal wells are located approximately 2000 feetnorth of the Site. The GAC treatment system began operation in 1986. The RAP stipulates thatthe treatment system will operate whenever the wells are used to supply the City's potable waterdistribution system.
The on-Site multi-aquifer well W23 was reconstructed as a Prairie du Chien-Jordan well and isbeing used as a source control well. The groundwater discharge from W23 is routed to the GACtreatment facility currently treating the discharge from Drift-Platteville source control wellsW420 and W421. The treated water is discharged to Minnehaha Creek.
A St. Louis Park well (SLP 4) is currently being used as a gradient control well. This well isapproximately 1-1/4 miles SE of the Site. The RAP also required the installation of three newmonitoring wells to assess the performance of this well as a gradient control system. If thegradient control system does not operate as required, the pumping rate of SLP 4 will be modifiedor additional gradient control wells will be installed.
- Ironton-Galesville Aquifer
The EPA and MPCA gave authorization to the City to stop pumping On-Site well W105 onDecember 4, 1991. The City will begin periodic monitoring of the well to ensure that DrinkingWater Criteria are not exceeded. In addition, if any municipal Ironton-Galesville well is installedwithin one mile of on-Site W23, it must be sampled annually for PAHs.
- Mt. Simon-Hinckley Aquifer
The only action for this aquifer required by the RAP is the annual monitoring (30 years) of fourmunicipal drinking water wells for PAHs. The wells that are currently being sampled, as well astheir distance and direction from the Site, are: 1) Well SLP 11, approximately 2000 feet north, 2)Well SLP 12, approximately 6625 feet south, 3) Well SLP 13, approximately 7500 feet north,and 4) Well SLP 17, approximately 2875 feet east.
In addition, if any municipal Mt. Simon-Hinckley well is installed within one mile of on-SiteW23, it must be sampled annually for PAHs.
- Operable Unit: Multi-Aquifer Wells
In 1978-1979, twenty-nine multi-aquifer wells were abandoned in areas where the surficialaquifers were most contaminated with PAHs and/or phenolics.
The two on-Site multi-aquifer wells, W23 and W105, were reconstructed in the mid-1980's. They are presently being used as source control wells.
A RAP-required plan for investigating suspected multi-aquifer wells, located in contaminatedareas of the Drift-Platteville, which are open to the Prairie du Chien-Jordan, Ironton-Galesville,or Mt. Simon-Hinckley aquifers, was submitted in September 1987. This investigation plan wasreviewed in conjunction with the review of the investigation plan for multi-aquifer wells open tothe St. Peter aquifer. This plan was submitted by the City in March, 1991. The results of thisplan will be used to recommend which leaking multi-aquifer wells, if any, should be abandonedor reconstructed.
- Operable Unit: Near-Surface Contamination
When the on-Site buildings were demolished in the early 1970's, visibly contaminated soils wereexcavated and replaced with clean fill. Excavated soil and demolition debris was moved to thewestern edge of the Site, covered, and vegetated. The Site was also graded and vegetated withgrass.
By 1980, two lined storm water retention ponds had been constructed. One pond is located in thesouthern portion of the Site and the other is approximately 1,500 feet south of the Site. Theponds are connected by a culvert. Water discharges from the southern pond to a wetland north ofMinnehaha Creek. The ponds effectively control surface water run-off from the Site.
The CD-RAP required Reilly to cover, with one foot of clean fill, existing sediments andvegetation in eight portions of the wetland area south of the Site and west of Louisiana Avenuebetween Walker and Lake streets to protect migratory waterfowl. The filling was completed in1986; the total area filled was approximately 4.5 acres.
In late 1992, the EPA Superfund Innovative Technology and Evaluation (SITE) team, MPCA andthe City of St. Louis Park will take soil borings in a small test area in the southeast corner of theSite. The samples will be tested to see if soil contaminants (primarily PAHs) to see if they canbe broken down by naturally-occurring bacteria. If the PAHs are broken down, a pilot study tobiovent the contaminated soils will be done. Bioventing involves injecting air into the soil toenhance bacterial growth and their capacity to breakdown the contaminants.
The Office of Health Assessment of ATSDR wrote a Preliminary Health Assessment for theReilly Tar and Chemical Corporation Site (dated January 31, 1989). The primary documentsmade available to the MDH for review, and used in the preparation of this Public HealthAssessment, are listed below:
- United States of America, et al., vs. Reilly Tar & Chemical Corporation, et al., U.S. DistrictCourt, District of Minnesota, Civil No. 4-80-469 (Consent Decree).
Issue Statement regarding the Request for Approval of a Consent Decree with the Reilly Tar &Chemical Corporation and Other Parties, etc. Prepared by the Minnesota Pollution ControlAgency's Solid and Hazardous Waste Division, Site Response Section. April 22, 1986.
Record of Decision, Reilly Tar, Minnesota. U.S. Environmental Protection Agency. May 25,1984.
Assessment of Ground-Water Contamination by Coal-Tar Derivatives, St. Louis Park Area,Minnesota. U.S. Geological Survey. 1984.
Record of Decision, Reilly Tar and Chemical Corporation Site, St. Peter Aquifer, St. Louis Park,Minnesota. U.S. Environmental Protection Agency and the Minnesota Pollution ControlAgency. September 28, 1990.
Drift-Platteville Aquifer Northern Area Remedial Investigation Report. ENSR Consulting andEngineering. June 19, 1989.
St. Peter Aquifer Remedial Investigation Report. ENSR Consulting and Engineering. July 21,1989.
The above documents, additional documents referenced in the body of this document,consultations with MPCA project staff, and site visits form the basis for this Public HealthAssessment.
Site visits were conducted by MDH staff on March 14 and April 5, 1991 and May 4, 1992; a jointvisit by MDH and MPCA project staff was made on March 20, 1991. A four-lane street(Louisiana Avenue) runs north-south through the eastern portion of the Site. The majority of theSite west of Louisiana Avenue is flat and well vegetated (grass). The on-Site storm waterretention pond had a considerable amount of water in it; a number of geese were seen in thispond. Three separate residential developments (rental condominiums and/or apartments) are on-Site; one each in the NW, NE, and eastern portions of the Site (see Figure 2). Signs at the on-Site parking areas designate the portion of the Site west of Louisiana Avenue as a park. Thereare paved walking paths running through this part of the Site as well as a soccer field (two soccernets were seen). Children were seen playing in the northern portion of the park (near the rentalunits) in May, 1992. There are light industrial facilities, businesses, and a restaurant/bar east ofLouisiana Avenue. There was no visual evidence of authorized or unauthorized site activitiesinvolving soil disruption, construction activities, or on-Site water use in these areas of the Site.
There was debris on the SW portion of the Site which may constitute a potential hazard. On thisportion there is an area of high ground that runs from the southwestern edge to the west-centraledge of the Site (see Figure 2). This "hill" was created when excavated soil and demolitiondebris (from the dismantling of the former plant) were piled there in the early 1970's. Erosionalgullies were observed on the SW, NW, northern, and east-central faces of the hill. Materials/debris such as rocks, rotted wood, and pieces of bricks, cement and asphalt weresticking out of the soil in these places. Chunks of shiny black, solidified coal tar were alsosticking out of a gully on the northern slope. A large tire was also sticking out of the soil on theeastern slope. The top portion of the hill was fairly well vegetated with grass, but still had anumber of bare spots. Other portions of the slopes are also fairly well to well vegetated withshort grasses. Eleven single-family homes back up directly (at the same elevation) to the hill.
The northern one-half of the western edge of the Site is bordered by Oak Hill Park. Single-family residences and/or apartments either border the Site or are very close to it to the north,west, southwest, and east. There are light industrial facilities and businesses/warehouses south ofthe Site.
The Site is located in the city of St. Louis Park (a suburb of the city of Minneapolis) in south-central Hennepin County, Minnesota. The 1988 estimated population of Hennepin County was989,956 (410,705 households). The 1988 estimated population of St. Louis Park was 43,700(20,043 households).
There are currently three rental condominium and/or apartment complexes, light industrialfacilities, and businesses on the Site. There are also many single and multiple family residencesin the immediate vicinity of the Site; some border the Site directly, while others are separatedfrom the Site by a city street. The area within one-half mile (approximate) of the respectiveborders of the Site is zoned by the city of St. Louis Park as follows:
- North: Primarily middle class single-family residences including areas of two-family residencesand commercial businesses.
East: Primarily middle class single-family residences and industrial districts with smaller areasof multiple-family residences and general businesses. A branch of the Hennepin Co. librarysystem, a community center, and the St. Louis Park Senior High school also are within this area.
South: Primarily industrial districts and middle class single-family residences. MethodistHospital is approximately two-thirds of a mile from the Site in this direction.
West: Primarily middle class single-family residences with smaller areas of residence-businessdistrict combinations and multiple-family residences. There is a shopping mall, elementaryschool, and approximately five park areas, one of which directly abuts the Site, also within thisarea.
The Site itself is zoned by the City as a planned unit development district.
Minnehaha Creek is approximately 0.5 miles south of the Site. The water level in the creekfluctuates dramatically throughout the year depending on snow melt and rainfall. During periodsof high water flow, the portion of the creek in the area of the Site is used for canoeing andoccasional wading. The creek is not used for fishing.
As noted earlier, the MDH closed six St. Louis Park municipal wells and one Hopkins municipal well during 1978 - 1980 because of PAH contamination. Because several PAHs are considered to be human carcinogens, the MDH's Division of Disease Prevention and Control compared the cancer incidence rates in St. Louis Park with those of three other areas in 1979 (6). These areas were: the city of Edina which is on the southern border of St. Louis Park, the city of Richfield which is approximately 2-1/2 miles SE of St. Louis Park, and the entire Minneapolis-St. Paul Standard Metropolitan Statistical Area (SMSA) (6). Richfield was selected because of it's similarity to St. Louis Park in a variety of social and economic characteristics; Edina was selected because the PAH contamination was thought to be moving in that direction; and theentire SMSA was used as the major comparison area.
In past years, Minnesota had no systematic method for monitoring cancer occurrence, so cancer incidence rates could not be calculated. As of January 1, 1988, the Minnesota Cancer Surveillance System began collecting data on cancer. This cancer surveillance system is a statewide system which collects information on all pathologically-confirmed cancers that have been diagnosed in Minnesota residents. Since the surveillance system was implemented only a short time ago, there will not be sufficient data for analysis for several more years.
Community complaints regarding contamination of wells and odors from air emissions havedated back to the 1930's. These complaints became more common during the late 1940's andinto the 1950's when extensive residential development was taking place in the area. Complaintsabout problems with soil and surface water contamination and odors continued through the late1960's (MPCA filed suit against Reilly in 1970).
Between 1978 and 1981, MDH closed six municipal wells in St. Louis Park and one inneighboring Hopkins because of PAH contamination. Because of the documented contaminationof part of their drinking water supply, the community expressed concern about potential healtheffects caused by ingesting these compounds. This concern escalated when the 1979epidemiological study performed by MDH showed the age-adjusted rates for breast cancer andall cancers combined were significantly higher in St. Louis Park females when compared tofemales in each of three other study areas.
In recent years, the City of St. Louis Park has received, on average, 2-4 calls per year regardingthe association between ingestion of PAHs and subsequent development of cancer (especiallybreast cancer) (7).