The Munisport Landfill site is an inactive landfill in, and owned by, the City of North Miami, Florida. This site is in an urban area adjacent to the Oleta River Recreational Area, a state mangrove preserve, and Biscayne Bay. Soil, sediments, surface water, and ground water are contaminated. We selected ammonia, benzene, di(2-ethylhexyl)phthalate, cadmium, carbon disulfide, chloromethane, coliform bacteria, dieldrin, lead, methylene chloride, pentachlorophenol, polychlorinated biphenyls (PCBs), styrene, vanadium, and zinc as contaminants of concern.
Approximately 1,500 people live in Highland Village mobile home park southwest of the site. These residents are concerned they have been exposed to contaminated dust and stormwater run-off and children trespassing on the site have been exposed to contaminated soil and water. Accidentally ingesting contaminated soil and surface water, and breathing contaminated smoke are completed human exposure pathways. Children who swam in the landfill lakes risked bacterial and viral infections. Air sampling was too late to determine the health risk from breathing contaminated smoke from the 1990 landfill fire. Although it is unlikely that this site is the source, eating polychlorinated biphenyl (PCB) contaminated fish and oysters from Biscayne Bay over a lifetime may affect the immune system and result in a "low" increased risk of cancer.
Based on the available data, we categorize the Munisport Landfill site as an indeterminate public health hazard. Data are either not available or inadequate for all environmental media to which humans may be exposed. Except for coliform bacteria, the available environmental data do not indicate that humans are being or have been exposed to levels of toxic chemicals that would be expected to cause adverse health effects. This conclusion is based on the limited data currently available and may change once the surface soil and landfill material have been adequately characterized. The data are inadequate to determine if there has been an increased rate of cancer in the Highland Village mobile home park.
Additional surface soil samples, fill material samples, and up-to-date lake water samples are necessary to adequately characterize the extent of contamination. Public access to this site should be restricted and warning signs posted as required by Florida law. Dust generated during any remediation, construction, or development that removes vegetation or uncovers landfill material should be controlled and nearby residential air monitored for site related contaminants. The appropriate agency should investigate the extent of PCB contamination in Biscayne Bay fish and oysters.
The Florida Department of Health and Rehabilitative Services (HRS), in cooperation with the Agency for Toxic Substances and Disease Registry, will work with other agencies to ensure these recommendations are followed. Florida HRS will inform the community about health risks from exposure to site-related contaminants and apply for funding for a disease symptom and prevalence study.
The Florida Department of Environmental Regulation will sample stormwater run-off in Highland Village and will monitor closure of the landfill portion of the site. The Environmental Protection Agency will monitor design and performance of the ground water cleanup and will require air monitoring where appropriate.
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 Munisport Landfill site. ATSDR, located in Atlanta, Georgia, is a federal agency within the U.S. Public Health Service, U.S. Department of Health and Human Services. ATSDR is authorized by the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) to conduct public health assessments at hazardous waste sites. Specifically, Florida HRS and ATSDR will determine whether health effects are possible and will recommend actions to reduce or prevent them.
A. Site Description and History
The Munisport Landfill site is an inactive landfill in the City of North Miami, Dade County, Florida (Figure 1, Appendix A). The site is about 2,000 feet northwest of Biscayne Bay. It is bordered on the north by N.E. 151st St., on the east by Florida International University, on the south by N.E. 135th St., and on the west by Biscayne Blvd.(Figure 2, Appendix A). This 291 acre site can be divided into 4 areas: a 170-acre landfill, 15 acres of uplands, 93 acres of altered wetlands, and 13 acres adjacent to Biscayne Bay that are separated from the rest of the site by the State of Florida mangrove preserve (Figure 3, Appendix A).
In 1970, the City of North Miami purchased 350 acres of land on Biscayne Bay. In 1972, the City of North Miami leased 291 acres of this land to Munisport, Inc. to develop a recreational facility. Starting in 1974, Munisport operated a landfill to fill in low-lying areas of this site. Munisport ceased landfill operations in 1980 and in 1981, the Florida Department of Environmental Regulation (DER) revoked their operating permit. In 1983 the Environmental Protection Agency (EPA) added this site to the Superfund National Priorities List (NPL). In 1985, ATSDR visited the site and issued a health assessment. ATSDR concluded that existing data were inadequate to assess the public health threat and recommended EPA conduct a remedial investigation (1). EPA conducted a remedial investigation and found that leachate from this landfill (primarily ammonia) threatens the environmental health of Biscayne Bay, but does not threaten human health. In January 1989, Dade County Public Health Unit personnel removed a small pile of hospital waste from the landfill. In a 1990 Record of Decision (ROD), EPA consulted with ATSDR and concluded that the site did not pose a threat to human health (31, 32). In this ROD, EPA outlined plans to intercept and treat the contaminated ground water and to relinquish control of the landfill portion of the site to the state. For about 6 weeks in March and April 1990, an underground fire burned at this landfill. Nearby residents reported that thick black smoke from this fire burned their eyes and throats and forced them to stay indoors. EPA was unable to mobilize an air sampling team until the fire subsided.
As a result of landfill operations, the original site topography has been altered. Eight borrow pits were excavated to provide cover for material deposited in the landfill. These borrow pits are now filled with water and together cover an area of about 16 acres. The land surface in the northern part of the site is gently rolling. The land surface in the southern part of the site is mostly flat. A 30 foot high mound of soil exists in the middle of the landfill.
There has been no remediation at this site since landfill operations ceased in 1980. Most of the site is heavily vegetated. There are no buildings or other structures on the site. Site access is poorly restricted and there are few warning signs. The City of North Miami is the current site owner. The City of North Miami is designing a system to extract and treat ammonia contaminated ground water. The City of North Miami is closing the landfill portion of the site pursuant to Florida law. There are plans to build an amphitheater and a racetrack on the landfill portion of the site.
B. Site Visit
Mr. Randy Merchant and Mr. Bruce Tuovila, Florida HRS, visited the site on December 11 and 12, 1991. They observed that most of the site was heavily vegetated. A fence along the southern and western site boundaries had numerous access points. There were some warning signs along the site boundary but they were too few to meet the requirement of Florida DER Rule 17-736 and Florida Statutes 403.704 and 403.7255. They observed the nearest residence in Highland Village is about three feet from the site boundary. Heavily worn paths indicated that people frequently trespass across this site. They saw three 10-12 year old boys riding bicycles and carrying fishing poles along the southeast site boundary. They also saw one teen-age boy walking across the site.
Mr. Merchant and Mr. Tuovila attended an EPA sponsored public meeting on December 11, 1991 and noted community health concerns. They attended the Munisport Landfill Technical Advisory Committee meeting on December 12. They also reviewed the Munisport Landfill files at the Dade County Public Health Unit, Environmental Health Section. No environmental samples were collected by Mr. Merchant or Mr. Tuovila.
C. Demographics, Land Use, and Natural Resource Use
The City of North Miami which is south and west of the site has approximately 50,000 people. The City of North Miami Beach, northwest of the site, has a population of approximately 36,000. In 1992 there were approximately 1,500 people living in Highland Village mobile home park immediately southwest of the site (2). The nearest residence in Highland Village is about three feet from the landfill boundary. The north campus of Florida International University, located immediately east of the site, has an enrollment of approximately 6,000 students, about 600 of whom reside in on-campus dormitories (3). Approximately 830 students, ages 5 to 12, attend Natural Bridge Elementary School about 0.5 mile east of the site. These students are from neighborhoods west of Biscayne Boulevard and from Highland Village (4).
The racial makeup of Highland Village is predominately white; the economic status is low to middle income. Some residents are French-Canadian and only reside in Highland Village during the winter months.
The land use around the site is mostly recreational, residential, and light commercial (Figure 4, Appendix A). There is little or no agriculture or hunting in this area. North of the site is a municipal sports stadium and a wastewater treatment plant. East of the site is Florida International University and the Oleta River Recreational Area. Swimming, boating, and fishing are popular activities at Oleta River Recreational Area. Southeast of the site is a State mangrove preserve and Biscayne Bay. Highland Village mobile home park is south and southwest of the site. Although the site is within the City of North Miami, Highland Village is in the City of North Miami Beach. South of Highland Village is a marina on a canal connected to Biscayne Bay. West of the site, along Biscayne Boulevard (U.S Highway 1), are light commercial developments: an abandoned drive-in theater, a U.S. Post Office, and a KOA campground.
Two facilities near this site, Sparkletts Water Systems Aquavend and Magnum Marine Corporation, reported releases of chemicals from 1987 to 1989 under the EPA Toxic Chemical Release Inventory program. The Dade County Department of Environmental Resources Management (DERM) reports three sites within 0.5 mile of the site that have leaking underground petroleum storage tanks. We will discuss environmental contamination from these sources in the Environmental Contamination and Other Hazards section. We are unaware of any other hazardous waste sites within 0.5 mile of this site.
Natural Resource Use
The Biscayne Aquifer which underlies the Munisport Landfill site is the sole source of drinking water for this part of the state. The ground water in the vicinity of this site, however, is not potable because of high salinity from saltwater intrusion. Although there have been reports of private well use in this area as late as 1985, most homes and businesses are supplied with municipal water from wells further inland.
There are numerous surface water bodies on and around this site. Eight lakes exist on the site as the result of past excavations. The Oleta River north of the site and Arch Creek/Southern Canal south of the site drain into Biscayne Bay. The Oleta River Recreational Area and Biscayne Bay are used for recreational swimming, skiing, and fishing. Although Biscayne Bay is closed for commercial oyster harvesting, individuals collect oysters for their own consumption.
The Munisport Landfill site is located next to a State mangrove preserve and Biscayne Bay. The State mangrove preserve is important as a source of food for the aquatic food chain. This preserve is part of the Biscayne Bay Aquatic Preserve established to maintain the biological integrity of the entire system. This preserve provides detritus, a food source for many small aquatic organisms such as invertebrates, various shellfish, and forage fish. These organisms in turn are food for larger predatory fish in Biscayne Bay, the Gulf of Mexico, and the Atlantic Ocean. This area, along with other wetlands, serves as a breeding and nursery ground for many of the fish species found in Biscayne Bay and the Atlantic Ocean. Other important functions of these wetlands include bird and other wildlife habitat, water quality improvement, flood protection, and shoreline erosion control.
D. Health Outcome Data
Guided by community health concerns, Florida HRS epidemiologists reviewed the Florida Cancer Data System (FCDS). FCDS is Florida's statewide cancer registry. It covers all newly diagnosed cases of cancer (except for some forms of skin cancer) reported since 1981. The FCDS is a program of Florida HRS and is operated by the University of Miami School of Medicine. Florida HRS epidemiologist analyzed the FCDS for all cancers reported through 1987, the latest year for which data were available. They searched the 33181 zip code which includes neighborhoods around the Munisport Landfill. ZIP codes are the smallest geographical unit searchable in the FCDS. We discuss the results of this review in the Public Health Implications, Health Outcome Data Evaluation section.
COMMUNITY HEALTH CONCERNS
About 10 to 20 residents of Highland Village mobile home park, which borders the southwest corner of the landfill, have expressed health concerns. We compiled these concerns from the December 1991 public meeting, telephone conversations with community leaders, community newsletters, newspaper articles, and EPA reports. We address these health concerns in the Public Health Implications, Community Health Concerns Evaluation section.
Air Exposure Health Concerns
1. Highland Village residents are concerned that until the landfill closed and heavy vegetation covered the site, they were exposed to contaminated dust including asbestos. They are concerned that rashes, respiratory illnesses, and infections they suffered in the 1970's and 1980's were caused by exposure to this dust. They are concerned that they will suffer health effects from exposure to contaminated dust resulting from future remediation and/or construction on the landfill.
2. Highland Village residents are concerned that toxic smoke from the March/April 1990 landfill fire aggravated existing respiratory conditions and may result in other long-term health effects. They are concerned that the April 10-11, 1990 EPA air monitoring was too late to measure the maximum concentrations of toxic chemicals generated by this fire.
3. Highland Village residents are concerned that they may suffer adverse health effects from continuous exposure to gases such as methane, benzene, and styrene emitted from the landfill. They are concerned because the ambient air quality of their neighborhood has not been monitored.
Skin Exposure Health Concerns
4. Highland Village residents are concerned that they may suffer health effects from skin contact with contaminated stormwater run-off from the landfill that floods their neighborhood. They are concerned that the proposed remediation will increase the frequency of flooding of their neighborhood.
5. Highland Village residents are concerned that their children swam in the on-site lakes and may suffer health effects from exposure to toxic chemicals.
6. Highland Village residents are concerned that their children have suffered increased rates of eye irritation and infection from swimming at the Oleta State Recreation Area and in the lagoon adjacent to Florida International University.
7. The manager of a youth facility northeast of the site is concerned that their children developed serious skin infections after being cut or scratched.
Other Health Concerns
8. Highland Village residents are concerned that they may have been exposed to radiation from radioactive hospital waste disposed of in the landfill.
9. Highland Village residents are concerned that their children and other trespassers on the landfill may have suffered higher rates of infection from exposure to hospital waste.
10. Highland Village residents are concerned that they may suffer health effects from contact with snakes, scorpions, and spiders, that live in the dense undergrowth along the southern boundary of the landfill.
11. Highland Village residents are concerned that people who eat landcrabs from the tidal areas near the landfill may be exposed to toxic chemicals.
12. Highland Village residents are concerned that there have been an inordinately high number of cancers in their neighborhood during the past 10 years. They are concerned these cancers are caused by exposure to toxic chemicals from the landfill.
13. One Highland Village resident has experienced intermittent swelling of the face, hands, and feet. This resident is concerned the swelling is caused by exposure to site contaminants.
We address these health concerns in the Public Health Implications, Community Health Concerns Evaluation section.