Zellwood Groundwater Contamination Site
Site Summary ProfileEPA ID: FLD049985302
Location: Zellwood, Orange County, FL
Lat/Long: 28.731950, -081.613330
Congressional District: 03
NPL Status: Proposed 12/30/1982; Final: 9/08/2003
Affected Media: Ground water, Sediment, Soil
Cleanup Status: Construction complete - physical cleanup activities have been completed
Human Exposure Under Control: Yes
Groundwater Migration Under Control: Yes
Sitewide Ready for Anticipated Use: No
Site Reuse/Redevelopment: In continued use - manufacturing, warehouse/distribution, and office facilities.
Site Manager: James Hou (email@example.com)
Current Site Status
The Zellwood Ground Water Contamination site includes the area where several chemical companies have operated since the early 1960s. EPA placed the site on the National Priorities List (NPL) in 1983 because of contaminated ground water, sediment and soil resulting from facility operations. EPA, the Florida Department of Environmental Protection (FDEP) and the site’s potentially responsible parties (PRPs) have investigated site conditions and taken steps to clean up the site in order to protect people and the environment from contamination. Site PRPs addressed soil and sediment contamination by digging up contaminated material and solidifying it into a concrete structure referred to as a monolith. PRPs began monitoring contaminated ground water in 2002. Current data shows that ground water contaminant levels in the majority of the ground water monitoring wells are declining or stable. However, contaminant levels in a few monitoring wells have increased. EPA is requiring additional sampling to investigate these increases. In addition, ground water samples have found volatile organic compounds in ground water not related to the site. EPA is currently investigating the source of this additional contamination.
Thirty-six private drinking water wells are located within a half-mile of the center of the site; some of these wells are on site. Initial research by the St. Johns River Water Management District indicates drinking wells in the area are likely in the Floridan Aquifer while contamination is in the shallow and intermediate aquifers. EPA is working with the St. Johns River Water Management District to issue advisories and inform area well owners of current site conditions and to make sure well owners are able to have their wells tested.
The 57-acre site is located in Orange County, Florida, approximately a half-mile west of Zellwood and 25 miles northwest of Orlando. Several active industrial facilities as well as some undeveloped properties, including an open field and wooded wetlands, are located on the site. The site’s surroundings include residential developments, a nursery, citrus groves, and pastureland, as well as several other businesses.
Numerous companies have operated in this industrial area since the early 1960s. Beginning in 1963, Drum Service Company of Florida, a drum recycling facility, used two unlined ponds for treatment and disposal of wastewater generated as part of its operations. The Southern Liquid Fertilizer Company began operating at the site in 1970s; in 1980, the company redesigned its treatment system and stopped using these ponds for wastewater disposal. In 1981, the plant began to operate under another owner, the Douglas Fertilizer and Chemical Company. The same year, operators drained the ponds and sent contaminated sediments to an off-site landfill. Operators then filled in the ponds with clean soil. These businesses discharged wastewater from their production process and wash water used during in-house cleaning into three unlined lagoons.
The Zellwin Farms Company also operated a vegetable washing and packing plant in the area from 1960 to 1983. The facility discharged wastewater from the vegetable washing process into drainage ditches along Jones Avenue.
Site investigations found contamination in ground water, sediment and soil that could potentially harm people in the area. Contamination resulted from former disposal practices of wastewater and wash water at the site. Contaminants of concern in site soil and sediment included metals, volatile organic compounds, polycyclic aromatic hydrocarbons and pesticides. Contaminants of concern in site ground water included numerous metals and nutrients such as ammonia, nitrates and nitrites.
Site PRPs addressed soil and sediment contamination by digging up the contaminated material and solidifying it into a concrete structure referred to as a monolith. The PRPs covered the on-site monolith with soil and fenced it.
People can be exposed to site contamination primarily by drinking contaminated ground water. The Saint John’s River Water Management District has listed the site as a ground water delineation area, which means all wells placed in the area require the District’s approval. Any permitted water wells must meet specific well construction and water testing criteria prior to well use. Orange County also enforces zoning restrictions that limit land uses at the site and surrounding properties to industrial and agricultural uses.
A 2007 well survey identified 36 private drinking water wells within a half-mile of the center of the site; some of these wells are on site. Ground water flow at the site is to the south/southwest. Based on the location of many downgradient wells, multiple private drinking wells might be at risk. Initial research by the St. Johns River Water Management District indicates drinking wells in the area are likely in the Floridan Aquifer while contamination is in the shallow and intermediate aquifers. EPA is working with the St. Johns River Water Management District to issue advisories and inform area well owners of current site conditions and to make sure well owners are able to have their wells tested.
Investigation and Cleanup Responsibility / Oversight
Site PRPs lead site investigation and cleanup activities, with oversight provided by EPA and FDEP.
Site Cleanup Plan
Site investigations and cleanup activities have focused on two areas, which EPA refers to as operable units, or OUs. These areas include OU-1: contaminated soil and sediment; and OU-2: contaminated ground water.In 1987, EPA issued a cleanup plan (a Record of Decision or ROD)
- Digging up contaminated soils and sediment.
- Incinerating the contaminated material on site.
- Disposing of the incinerated material off site.
In 1990, EPA issued an amendment to the 1987 cleanup plan (ROD) for OU-1. Instead of incinerating contaminated soil and sediment and disposing of it off site, the revised plan called for solidifying and disposing of the contaminated soil and sediment on site.
In 2000, EPA issued a cleanup plan (a ROD) for OU-2. The plan included the following activities:
- Using monitored natural attenuation for ground water contaminants.
- Installing permanent ground water monitoring wells.
- Implementing a plan to measure and evaluate the effectiveness of monitored natural attenuation.
- Implementing institutional controls in the form of EPA-issued ground water use advisories and zoning regulations.
The site’s PRPs cleaned up contaminated soil and sediment (OU-1) in two phases. In Phase 1, PRPs dug up and stockpiled 7,000 cubic yards of contaminated soil and sediment. They then sampled the area to make sure they had dug up all contaminated soil and sediment. In Phase 2, the PRPs solidified all contaminated material into a concrete structure referred to as a monolith. PRPs then covered the monolith with soil and planted it with grass to prevent erosion. The PRPs completed the monolith in 1994.
The site’s PRPs started contaminated ground water (OU-2) monitoring in 2002 after installing two pairs of downgradient monitoring wells. Current ground water data shows that contaminant levels in the majority of the ground water monitoring wells are declining or stable. However, contaminant levels in a few monitoring wells have increased. EPA is requiring additional sampling to investigate these increases. In addition, ground water samples have found volatile organic compounds in ground water not related to the site. EPA is currently investigating the source of this additional contamination.
The site’s third Five-Year Review, completed in September 2011, stated that additional information would need to be collected before EPA could determine whether the site’s cleanup approach continues to protect people and the environment from remaining site contamination. In the Five-Year Review, EPA anticipated it would take 18 months to collect the necessary information.
In 2001, EPA entered into a legal agreement with several site PRPs – Drum Sendee Company of Florida, IFCO Industrial Container Systems FL, LLC and IFCO Industrial Container Systems, Inc. – to implement site cleanup activities. IFCO Industrial Container Systems FL, LLC maintains the monolith and provides annual ground water sampling reports to EPA.
EPA has worked with the community and its state partner to develop a long-term cleanup plan for the site, reflecting the Agency’s commitment to safe, healthy communities and environmental protection. Community engagement and public outreach are core components of EPA program activities.
EPA has conducted a range of community involvement activities to solicit community input and to make sure the public remains informed about site activities throughout the cleanup process. Outreach efforts have included public notices, interviews and public meetings.
EPA is requiring additional investigations at the site to determine the effectiveness of the monitored natural attenuation remedy. The investigations will also help determine if the current cleanup approach can meet ground water cleanup goals in the 2000 OU-2 ROD in a reasonable timeframe. The site’s PRPs will continue area ground water monitoring until ground water meets cleanup goals.
A separate investigation into the source of volatile organic compound contamination in ground water coming from an off-site area is underway.
EPA completed the last Five-Year Review in 2011 and plans to complete the next Five-Year Review in 2016.
EPA keeps additional site documents and information in a site information repository at the location below. EPA also posts site documents, when available, on EPA’s CERCLIS Site Profile page. For documents not available on the website, please contact the Region 4 Freedom of Information Office.
Zellwood Elementary School
3551 Washington Street
Zellwood, FL 32798