The Chevron Chemical Co. (Ortho Division) Superfund site is a former pesticide formulation plant and truck repair facility in Orlando, Florida. This site is a public health hazard because some residents of the adjacent Armstrong Trailer Park may have unknowingly eaten small amounts soil contaminated with the pesticide chlordane. As a result, we estimate these residents have a moderately increased risk of liver cancer. Since Chevron cleaned up the chlordane-contaminated soil at this trailer park in 1994, we estimate that the remaining cancer risk is insignificant. Some nearby residents are concerned that exposure to contaminated dust, ground water, and surface water has affected their health.
In this public health assessment we evaluated the health threat of contact with the pesticides chlordane, DDD, DDT, dieldrin, and heptachlor epoxide. We selected these pesticides based on the likelihood of breathing contaminated dust and eating contaminated soil. We also evaluated the potential public health threat from drinking contaminated ground water and using nearby Lake Fairview.
Since we do not have any air monitoring data prior to 1992, we do not know the public health threat from breathing pesticide-contaminated air before that time. The concentrations of pesticides in the air during the 1992 site cleanup, however, were unlikely to cause any illness. We estimate that people who have lived along the western boundary of the Armstrong Trailer Park for more than 20 years may have a moderately increased risk of liver cancer. This increased risk is due to unknowingly eaten very small amounts of chlordane-contaminated soil. Since Chevron cleaned up the chlordane-contaminated soil in 1994, we estimate the increased cancer risk from exposure since then is insignificant. Although we estimate that drinking the contaminated ground water under the Armstrong Trailer Park is unlikely to cause any illness, we do not recommend drinking it. We did not assess the public health threat from using Lake Fairview since ground water monitoring data show that contamination has not traveled that far.
We recommend that Chevron maintain the grass cover or suppress dust to prevent any additional pesticide exposure. We recommend the Southwest Florida Water Management District prohibit any new private wells near this site or prohibit domestic use of the contaminated ground water. We will tell the long-term residents of the Armstrong Trailer Park about their risk of liver cancer and about the other conclusions of this public health assessment.
In this public health assessment, the Florida Department of Health and Rehabilitative Services (Florida HRS), in cooperation with the Agency for Toxic Substances and Disease Registry (ATSDR), evaluates the public health significance of the Chevron Chemical Co. (Ortho Division). Specifically, Florida HRS decides whether health effects are possible and recommends actions to reduce or prevent them. The Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA or Superfund) authorizes the ATSDR to conduct public health assessments at hazardous waste sites. The ATSDR, located in Atlanta, Georgia, is a federal agency within the U.S. Department of Health and Human Services.
There are uncertainties inherent in the public health assessment process. These uncertainties fall into four categories: 1) science is never 100% certain), 2) the inexactness of the risk assessment process, 3) the incompleteness of the information collected thus far, and 4) differences in opinion as to the implications of the information (NJDEP 1990). Scientists and public health officials incorporate uncertainties into risk assessments by using worst-case assumptions when estimating or interpreting health risks. They also incorporate uncertainties by using wide safety margins when setting health-related threshold values. Because of these actions, risk assessments tend to err on the side of protecting public health. Therefore, the assumptions, interpretations, and recommendations we make throughout this public health assessment err in the direction of protecting public health.
A. Site Description and History
The Chevron Chemical Co. (Ortho Division) Superfund hazardous waste site is in Orlando, Florida (Figure 1). This 4-acre site is in a mixed industrial/commercial/residential area at 3100 Orange Blossom Trail (Highway 441), three miles northwest of downtown Orlando (Figure 2). It is bounded on the north by the Armstrong Trailer Park and the 441 Trailer Park. It is bounded on the east by Orange Blossom Trail and Lake Fairview Commerce Center. Areas south and west of the site are light industrial (Figure 3). The site is level and contains no buildings or other structures. Grass covers the site and a 6-foot high chain-link fence with a locked gate surrounds it.
The Chevron Chemical Company, Ortho Division (Chevron) blended pesticides at this site between 1950 and 1976. The site included an office, a formulation (blending) building, storage tanks, a water tower, and rinsate ponds (Figure 4). Chevron blended chlordane, lindane, dieldrin, aldrin, parathion, and other pesticides with xylene, kerosene, mineral oil, mineral spirits, ethyl benzene, and aromatic naphtha. Before 1970 Chevron discharged contaminated rinse water to unlined ponds on site. As a result, they contaminated soil and ground water with pesticides. After 1970 they collected their rinse water and shipped it off site.
Aerial photographs from 1952 show a trailer park next to the north side of the site (EPA 1991). The Orange County Public Health Unit has records of this trailer park dating back to 1956 (Orange CPHU 1994).
In 1978 Robert Uttal purchased the property from Chevron and operated Central Florida Mack Truck until 1986. Central Florida Mack Truck serviced diesel engine trucks and disposed of waste oil, diesel fuel, paint, and cleaning solvents in the on-site rinsate ponds. In 1983, a Chevron consultant found pesticides in on-site soil and ground water (Dames & Moore 1983). Four years later in 1987, an investment-firm consultant found petroleum contamination in the ground water (Jammal & Associates 1987). Mr. Uttal leased the parking area for vehicle storage from 1987 to 1988 and leased the pesticide-blending building as a public-storage facility from 1989 to 1990. In 1989 an Environmental Protection Agency (EPA) consultant found extensive pesticide and petroleum contamination in both the soil and ground water (NUS 1990).
In January 1990, the Agency for Toxic Substances and Disease Registry (ATSDR) concluded that contact with contaminated surface soil was a public-health threat and recommended that the EPA restrict site access (ATSDR 1990). Three months later, Chevron built a fence around the site. In September 1990, Chevron consultants further defined the extent of soil and ground-water contamination (Brown and Caldwell 1990a). In a 1992 emergency removal action, contractors for Chevron demolished the buildings and excavated and shipped 23,000 tons of contaminated soil. They also treated 126,000 gallons of contaminated ground water and backfilled the site with clean fill (Brown and Caldwell 1992). The ATSDR concurred with the EPA's soil clean up goal of <5 mg/kg chlordane (ATSDR 1991).
In August of 1992, the EPA selected this site as a pilot for their Superfund Accelerated Cleanup Model program (SACM). In 1993 and 1994, Chevron purchased the property from the First Union Bank and the Resolution Trust Corporation following foreclosure. On January 18, 1994, the EPA proposed adding this site to the Superfund National Priorities List (NPL). The EPA based its proposed listing on remaining ground-water contamination. Between March and April of 1994, contractors for Chevron removed approximately 200 cubic yards of pesticide-contaminated surface soil from the southwest corner of the Armstrong Trailer Park (Task 1994a). The EPA finalized the listing of this site on the Superfund NPL on May 31, 1994. Also on May 31, 1994, contractors for Chevron completed their remedial investigation report (Task 1994a). To evaluate additional cleanup options, EPA contractors drafted a baseline risk assessment (B& V 1994) and Chevron contractors drafted a feasibility study (Task 1994b). The EPA hopes to select a final cleanup plan (Record of Decision) early in 1995. We prepared this public health assessment in response to the EPA's proposal to add this site to the Superfund list.
B. Site Visit
On July 29, 1993, Randy Merchant with the Florida Department of Health and Rehabilitative Services (HRS), Office of Environmental Toxicology (Tallahassee) visited the site. Representatives of the Orange County Public Health Unit, Environmental Health Section, accompanied him on this site visit. They drove around the site and through the Armstrong Trailer Park and the 441 Trailer Park. Grass covered the site and a 6-foot chain-link fence with a locked gate completely enclosed it. There were no structures on the site and no evidence of trespass. Some trailers in the Armstrong Trailer Park were within a few feet of the site boundary. They observed that the residents of both the Armstrong and 441 trailer parks were low income and predominantly white. On the evening of July 29, 1993, Mr. Merchant attended an EPA sponsored public meeting.
Mr. Merchant visited the site again on August 5, 1994. He observed that the site fence was in good repair and that there was no evidence of trespass. From the Armstrong Trailer Park, he noted about 0.2 acre of standing water (0-3 inches deep) in the northwest corner of the site. He noticed that Chevron contractors had placed sandbags along the northwest site boundary to contain site run-off. Mr. Merchant also toured the Armstrong Trailer Park and observed the southwest corner where Chevron contractors had excavated contaminated surface soil. He observed that, although the area was damp from recent rains, sod covered it and there was no bare soil. Mr. Merchant did not collect any environmental samples during either of these site visits.
From 4:00 to 7:00 PM on March 9, 1995, Mr. Merchant held a public meeting in the laundry room of the Armstrong Trailer Park. The purpose of this meeting was to solicit comment on the draft public health assessment report. Julia Winter, also with Florida HRS Office of Environmental Toxicology in Tallahassee, accompanied Mr. Merchant. The EPA Region IV community relations coordinator, the EPA site remedial project manager, two representatives from the Environmental Health section of the Orange County Health Department, and a representative from TASK Environmental, a Chevron contractor also attended this meeting.
The manager/owner of the trailer park along with 15 to 20 residents attended this meeting and expressed a wide range of concerns. They were concerned they were exposure to contaminated dust during the 1992 site cleanup. They complained of strong odors, skin rashes, burning eyes and noses, nausea, sore throats, and chest pains during that time. One residents complained that her children continue to suffer from skin rashes, runny noses, fever, bronchitis, and other flu-like symptoms. Some were concerned that fruits and vegetables grown at the trailer park were no longer safe to eat.
C. Demographics, Land Use, and Natural Resource Use
We estimate that in 1990, about 4,000 people lived within one mile of this site. We base our estimate on 1990 census data for Orange County census tract #126 (BOC 1990). Although the site is in census tract #124, most of the people within a one-mile radius of the site reside in tract #126. Tract #126 encompasses most of the College Park area and extends about 1.5 miles southeast of the site. Residents in this census tract are almost exclusively white (98%). The population is mostly middle age: the median age is 41. Seventy-five percent of the 1,910 housing units in this tract are owner occupied. Median yearly family income in this tract is about $41,000 (BOC 1990). Based on our observations, we estimate about 300 people live in the Armstrong and 441 Trailer Parks north of the site. Residents of these two trailer parks have low income and are predominately white.
Land use within one mile of the site is a mix of industrial, commercial, and residential. The areas north and east of the site are mainly residential. Lake Fairview is about 1,000 feet to the northeast. The areas south and west of the site are light industrial with few homes. Commercial development lines Orange Blossom Trail (US 441) northwest and southeast of the site.
Natural Resource Use
Ground water below the site is contained in two aquifers: the surficial aquifer and the Floridan aquifer. Ground water in the surficial aquifer starts about 10 feet deep and extends to about 25 or 30 feet deep. Ground-water flow in the surficial aquifer is northeast toward Lake Fairview (Task 1994a). The surficial aquifer is separated from the Floridan aquifer by about 50 feet of clay (the Hawthorne formation). The Floridan aquifer under the site starts at about 80 feet deep. Regional ground water flow in the Floridan aquifer is to the east and northeast (Task 1994a). Flow direction in the Floridan aquifer is influenced locally by the effects of pumping wells and drainage wells.
Beginning in 1948, the City of Orlando supplied water to all of the residents of the Armstrong and 441 Trailer Parks (the area over the contaminated ground water) (Orange CPHU 1993). Since the City of Orlando supplies water to homes and business immediately adjacent to the site, ground water is not a source of drinking water for nearby residents. In 1990 Chevron consultants identified eight wells within 1 mile of the site (Brown and Caldwell 1990b). This report, however, did not identify if these wells were used for drinking water. None of these wells are northeast of the site (in the direction of the surficial-aquifer ground-water flow).
Area residents use Lake Fairview, northeast of the site, for swimming, fishing, water skiing, and boating. There is no evidence of hunting in this area. We did not observe any home gardens in either the Armstrong or 441 Trailer Parks.
D. Health Outcome Data
We did not evaluate health outcome data for the Chevron Chemical Co. (Ortho Division). See the Public Health Implications, Community Health Concerns Evaluation section later in this report for details.
COMMUNITY HEALTH CONCERNS
Nearby residents have expressed some health concerns. We compiled these concerns from public meeting summaries, newspaper articles, and EPA reports.
1. A few residents of the Armstrong Trailer Park north of the site were concerned that breathing pesticide-contaminated dust during the 1992 soil removal would affect their health. Specifically, they complained of strong odors, skin rashes, burning eyes and noses, nausea, sore throats, and chest pains during that time.
2. A few nearby residents are concerned that contaminated ground water will reach their private wells and affect their health.
3. A few nearby residents are concerned that contaminated ground water will reach Lake Fairview and affect their health via consumption of fish, incidental ingestion of water, or skin absorption.
4. One nearby resident was concerned that their health had been affected by living near this site. This resident did not specify what illnesses they thought were site related. This resident was also concerned that the stress of living near a hazardous waste site had affected their health.
5. One nearby resident was concerned that their emphysema was aggravated by breathing contaminated dust from the site.
6. Some nearby residents were concerned that home-grown fruits and vegetables were no longer safe to eat.
7. One residents is concerned that her children continue to suffer from skin rashes, runny noses,
fever, bronchitis, and other flu-like symptoms.