Olin Corporation (McIntosh Plant)
Site Summary ProfileEPA ID: ALD008188708
Location: McIntosh, Washington County, AL
Lat/Long: 31.263880, -087.994450
Congressional District: 01
NPL Status: Proposed: 09/08/83; Final: 09/21/84
Affected Media: Ground water, Soil, Surface water, Sediment
Cleanup Status: Cleanup underway for ground water; feasibility study for Operable Unit 2 underway
Human Exposure Under Control: Yes
Groundwater Migration Under Control: Yes
Sitewide Ready for Anticipated Use: No
Site Reuse/Redevelopment: In continued use – an active chemical production facility is located on site
Site Manager: Beth Walden (firstname.lastname@example.org)
Current Site Status
The Olin Corp. (McIntosh Plant) site includes an area where the Olin Corporation (Olin) has operated a chemical manufacturing facility since 1952. EPA placed the site on the National Priorities List (NPL) in 1984 primarily because of contaminated ground water resulting from facility operations. The plant is both a Resource Conservation and Recovery Act (RCRA) facility and an NPL site. EPA, the Alabama Department of Environmental Management (ADEM) and Olin, the site’s potentially responsible party (PRP), have investigated site conditions and taken steps to clean up the site in order to protect people and the environment from contamination. A fish consumption advisory is in effect for a portion of the Tombigbee River near the site. A Record of Decision for OU-2 was completed in April 2014.The selected remedy is an in-situ cap with institutional controls and monitoring. This remedy will address the remaining contamination in the Olin Basin located next to the Tombigbee River. By monitoring and treating ground water, complying with RCRA requirements, enforcing institutional controls and conducting required Five-Year Reviews, EPA, ADEM and the site’s PRP continue to protect people and the environment from site contamination.
The site is located one mile east-southeast of McIntosh in Washington County, Alabama. Site surroundings include the Tombigbee River to the east and residential and commercial properties to the west. The Ciba-Geigy Corporation (Macintosh Plant) site borders the site to the north and River Road runs along the site’s southern edge. Broader site surroundings include industrial, commercial, agricultural and residential land uses.
The main plant and associated properties cover about 1,500 acres. From 1952 until 1982, Olin produced chlorinated organic pesticides, chlorine, caustic soda and sodium hypochlorite at the site. Presently, Olin produces chlorine, caustic soda and sodium hypochlorite and blends and stores hydrazide compounds at the site.
From 1952 to 1974, operators discharged plant wastewaters into the Tombigbee River. In 1980, Olin installed ground water monitoring wells to comply with a RCRA post-closure permit for solid waste management units (SWMUs) on site. These included former landfills, ponds, plant areas and a drainage ditch. Primarily because of contamination in ground water, EPA listed the site on the NPL in 1984.
Releases of mercury and organic chemicals such as benzene contaminated shallow ground water beneath the site. Discharges of wastewater containing mercury also contaminated wetlands next to the Tombigbee River. Investigators also found contamination in a 65-acre natural basin, located on the site property east of the active plant facilities.
Between 1984 and 1985, Olin, the site’s PRP, closed 10 designated SWMUs. In 1987, with EPA and ADEM approval, Olin initiated a RCRA corrective action program to address ground water contamination at the site. The program included a ground water pump-and-treat system. As part of the RCRA post-closure permit, Olin has also undertaken monitoring programs to make sure the plant continues to meet RCRA permit requirements and that past corrective actions remain effective.
Under the Superfund program, Olin addressed, improved and extended the cap covering the old plant landfill, the area considered the source of site contamination, between 1998 and 2004. Olin also enhanced the site’s ground water treatment system. EPA is currently evaluating how best to address contamination in the Olin Basin located next to the Tombigbee River, a floodplain and a wastewater ditch leading to the basin.
Residents are not using contaminated ground water from the affected aquifer, known as the Alluvial Aquifer. Parties monitor the Alluvial Aquifer on a regular basis to make sure the area of affected ground water contamination continues to decrease and remains contained within the site boundary.
Contamination has also affected ground water in the Miocene aquifer beneath the adjacent Ciba-Geigy Corporation (Macintosh Plant) site. ADEM is working with Olin to assess this contamination further. Although the Miocene Aquifer is a primary drinking water source, the McIntosh Water Department tests and treats the ground water prior to distributing it to make sure it is safe for people to drink.
The primary risks for residents living near the site are consumption of fish contaminated with mercury. The Alabama Department of Public Health has issued a fish consumption advisory (PDF) (17 pp, 500K, About PDF) (in table see, “Tombigbee River, Washington County, Vicinity of McIntosh Landing, river mile 60”) for the area of Tombigbee River near the site. People, including children and pregnant women, should limit meals of largemouth bass to two meals per month.
Institutional controls in the form of restrictive covenants are in place to prohibit the use of ground water in the Alluvial Aquifer on site and to prohibit the use of cleaned-up on-site surfaces.
Fencing surrounds all site treatment systems. Because Olin operates an active chemical production facility on site, only authorized persons may access the site.
Investigation and Cleanup Responsibility / Oversight
Olin, the site’s PRP, leads site investigation and cleanup activities, with oversight provided by EPA and ADEM.
Site Cleanup Plan
Site investigations and cleanup activities have focused on two areas, which EPA refers to as operable units, or OUs. These area include OU-1: the active production facility, SWMUs, and the upland area of the Olin property; and OU-2: the Olin Basin located next to the Tombigbee River, a floodplain and a wastewater ditch leading to the basin.
In 1992, EPA issued a cleanup plan (a Record of Decision, or ROD) for OU-1, which addresses the source of the contamination on the site as well as ground water contamination across the entire site. The plan included the following activities:
- Installing more wells to remove and treat contaminated ground water.
- Upgrading the existing cap over the old plant (CPC) landfill with a multimedia cap.
- Extending the clay cap covering the CPC landfill to an area west of the former plant.
- Conducting more ground water monitoring near sanitary landfills.
- Analyzing the long-term effectiveness of ground water treatment in reducing the spread of ground water contamination.
- Implementing land and ground water use restrictions.
EPA issued a cleanup plan (ROD) for OU-2 in the Spring of 2014, which addresses the sediment and surface water contamination in the Olin Basin and surrounding floodplain and the wastewater ditch The plan included the following activities:
- Multi-layered Cap. A multi-layered cap applied in-situ over approximately 80 acres of sediment exceeding the sediment cleanup levels.
- Additional Sampling and Analyses. Additional sampling and analyses will be performed in the channel connecting Round Pond to the Basin and the perimeter of the Round Pond floodplain soils that are often inundated, as well as the former wastewater and discharge ditch, to further refine the remedial footprint.
- Institutional Controls. The institutional controls (deed and restrictive covenant) that are currently in place as a result of OU-1 (Operable Unit 1) will be amended to include the OU-2 remedial footprint and use restrictions. Also, engineering controls, such as warning signs, including fish advisory signage, fencing, and security monitoring will be implemented to restrict access and prevent exposures to human receptors.
- Construction Monitoring. Construction monitoring for capping will be designed to ensure that the design plans and specifications are followed in the placement of the cap and to monitor the extent of any contaminant releases during cap placement.
- Maintenance. Maintenance of the in-situ cap will include the repair and replenishment of the layers where necessary to prevent releases of contaminants.
- Long-Term Monitoring. Long-term monitoring will include physical, chemical, and biological measurements in various media to evaluate long-term remedy effectiveness in achieving remedial action objectives (RAOs), attaining cleanup levels, and in reducing human health and environmental risk. In addition, long-term monitoring data is needed to complete the five-year review process.
Between 1984 and 1985, Olin closed 10 designated SWMUs.
In 1987, Olin started treating contaminated ground water under the RCRA corrective action program.
In 1990, Olin removed 11,407 tons of contaminated soil from the site.
Between 1998 and 2004, Olin implemented the OU-1 cleanup plan.
Efforts to prepare a cleanup plan (a ROD) for OU-2 are ongoing. In 2006, Olin constructed a berm, or raised barrier, with a gate around OU-2. Olin did this as part of a study to test whether sediments dropping out of trapped floodwater from the Tombigbee River would form an effective natural cover over contaminated sediments in the OU-2 area. This effort required a high degree of coordination between Olin, EPA, ADEM, the U.S. Fish and Wildlife Service, the National Oceanic and Atmospheric Administration, and the U.S. Army Corps of Engineers.
EPA has preliminarily concluded that since floodwaters entering the site contain low amounts of sediment and those sediments are difficult to capture, the sediments will not form an effective cover over contaminated areas. Olin completed the OU-2 remedial investigation and feasibility study in fall 2012. EPA issued the the OU-2 Record of Decision in April 2014.
The site’s second Five-Year Review, completed in 2011 for OU-1, found that the OU-1 cleanup approach currently protects people and the environment from contamination. For the cleanup approach to be protective over the long term, the Five-Year Review recommended follow-up actions.
EPA negotiated legal agreements with the site’s PRP to investigate and clean up the site. The PRP continues to fund site cleanup, monitoring and oversight activities.
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 site fact sheets, public notices, interviews and public meetings.
The OU-2 Proposed Plan Public Meeting was held in McIntosh in May 2013.
EPA is working with the site’s PRP to verify the long-term protectiveness of site ground water cleanup efforts.
EPA anticipates requiring the PRP to operate the site’s ground water pump-and-treat system until site ground water meets all cleanup goals.
Olin is conducting long-term monitoring and operation and maintenance activities in accordance with the RCRA corrective action program.
EPA will work with the site’s PRP in implementing the remedy as described in the Record of Decision for OU-2.
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 postssite documents, when available, on EPA’s CERCLIS Site Profile page and http://www.epa.gov/region04/foiapgs/readingroom/index.htm. For documents not available on the websites, please contact the Region 4 Freedom of Information Office.
Mcintosh Town Hall
206 Commerce Street
P.O. Box 385
McIntosh, AL 36553