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The five-acre Diaz Chemical Corporation (Diaz Chemical) site is located in Holley, New York. The area includes the Diaz Chemical facility and parts of the surrounding residential neighborhood.

The site is bounded on the north by Jackson Street, where both residential parcels and a parcel of land owned by Diaz Chemical, which includes a parking lot and a warehouse, are located. To the east, it is bounded by residential parcels on South Main Street. To the south and west, it is bordered by Conrail railroad tracks, and beyond that by undeveloped land and a group of buildings that are now vacant. The site is located about 25 miles west of Rochester and 50 miles east of Buffalo. The nearest municipal drinking water supply well is located 0.66 mile south of the site.

The property was initially used in the 1890s for tomato processing and cider vinegar production before being purchased by Diaz Chemical in 1974. Diaz Chemical was a manufacturer of specialty organic intermediates for the agricultural, pharmaceutical, photographic, color and dye and personal care products industries. The Diaz Chemical product line varied over the years of operation, but primarily consisted of halogenated aromatic compounds and substituted benzotrifluorides.

The Diaz Chemical facility had a long history of spills, releases and discharges of various materials to the environment that dated back to about 1975. An accidental air release occurred on January 5, 2002, when a reactor vessel in a process building overheated, causing its safety valve to rupture and release approximately 75 gallons of a chemical mixture through a roof stack vent. The release consisted primarily of a mixture of steam, toluene, and 2-chloro-6-fluorophenol, as well as related phenolic compounds. The splash zone for the release extended northeast from the facility into the neighboring residential community. Soon after the release, people complained of acute health effects, such as sore throats, headaches, eye irritation, nosebleeds, and skin rashes. As a result of the release, residents voluntarily relocated from some of the homes in the neighborhood to area hotels with assistance from Diaz Chemical.

In May 2002, the Environmental Protection Agency (EPA) assumed responsibility for the relocation expenses of the residents who remained relocated at that time. In June 2003, Diaz Chemical filed for bankruptcy and abandoned the facility, leaving behind large volumes of chemicals in drums and tanks. Immediate cleanup actions at the site eliminated the immediate threats to human health and the environment.


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What Has Been Done to Clean Up the Site?


The site is being addressed in two stages: immediate actions and a long-term remedial phase focused on the cleanup of the entire site.

Immediate Actions: In 2002, the State of New York obtained a court order that required Diaz Chemical to continue to fund the relocations until an appropriate environmental and health assessment was performed for the affected neighborhood. After Diaz Chemical sought to discontinue the relocations for ability-to-pay reasons, EPA assumed responsibility for the relocation expenses of the residents who remained relocated at that time. EPA then started a preliminary assessment of the affected neighborhood and performed sampling of air, soil, interior surfaces and household items. EPA also secured the site and removed contaminated materials, drums, piping, reactor vessels and storage tanks.

From 2003 to 2007, EPA secured the site and removed all hazardous substances within drums, and tanks, removed facility piping, and the dismantled the Diaz Chemical production buildings. These activities concluded in August 2007.In 2007, EPA shipped over 8,000 drums and over 112,000 gallons of hazardous wastes off site for reuse or disposal. A total of 105 reactor vessels and 34 storage tanks were emptied and decontaminated. All vessels and tanks were sent off site for recycling or disposal. Over 51,000 linear feet of facility piping (accounting for 95 percent of the existing piping) was dismantled and removed. About 800 gallons of waste within the piping was recovered and disposed of. Over 750 tons of scrap metal and 500 tons of concrete were recycled. Over 1,200 cubic yards of debris and 3,100 tons of contaminated concrete were disposed of.


Long-Term Cleanup: From 1994 to 1999, Diaz Chemical conducted an investigation under the direction of the New York State Department of Environmental Conservation (NYSDEC). The results found soils and groundwater on the property and nearby areas contaminated with volatile organic compounds and semi-volatile organic compounds. NYSDEC issued a Record of Decision (ROD) in 2002. The ROD selected a remedy for the site that included groundwater extraction via an interceptor trench and treatment. Diaz Chemical subsequently installed a groundwater extraction and treatment system.

In 2005, EPA signed a ROD for the property acquisition and permanent relocation of eight owner-occupants and two individual tenants who remained in temporary quarters at that time. EPA purchased all eight homes and provided the owners with relocation assistance. Furthermore, two individual tenants were assisted with relocating into new rental dwellings.

In 2005, EPA started a remedial investigation/feasibility study (RI/FS) to determine the nature and extent of contamination at the site and to identify and evaluate remedial alternatives. This work included installing additional groundwater monitoring wells and sampling them along with existing monitoring wells to better delineate the contaminated groundwater plume. It also included the collection of soil samples both on the site property and residential areas indoor air sampling at nearby homes potentially affected by the groundwater plume.

Based on the indoor air sampling results, vapor mitigation systems were installed at two homes in 2007. Due to water infiltration issues into one of the basements, the mitigation system was removed and replaced with a carbon filtration system in 2009. Also at that time, a carbon filtration system was installed in another home.

Based upon the results of the RI/FS, in 2012, EPA selected a cleanup plan for the site which included in-situ thermal treatment of contaminated soil and groundwater located at the Diaz Chemical property and natural processes to address the groundwater contamination downgradient of the source areas. The cleanup plan also included building demolition to obtain access to contaminated soils on site.

The RI/FS determined that site-related contamination does not exist in the surrounding residential area. Therefore, a cleanup for the neighborhood, including the eight EPA-owned residential properties, is not necessary (other than the continued operation and maintenance of three existing residential vapor mitigation systems).  Accordingly, EPA determined that the sale or transfer of the eight EPA-owned properties is consistent with the final cleanup and negotiated an agreement with the Village of Holley and the Village of Holley Development Corporation related to the sale of the properties.  The properties were transfered to the Village of Holley Development Corporation (VHDC) in June 2017.  The VHDC, working with a local realtor and law firm, sold all the houses in September 2017. 






In 2015, all of the remaining on-site buildings (except for Warehouse 9, which is located to the north of Jackson Street across from the main property, and Warehouse F, located on the facility proper) were demolished to facilitate the implementation of the thermal remedy noted above.

During this period, six buildings were cleared of debris and hazardous materials and demolished.  Asbestos-containing materials, fluorescent bulbs and PCB ballasts were identified, removed and disposed. The demolition debris was segregated for salvage and recycling or disposal in a hazardous waste landfill.  Eight hundred and sixty tons of construction and demolition debris were shipped off site for proper disposal.

To facilitate the implementation of the remedy, f approximately 1,200 feet of a 12-inch water main that traversed the site was relocated in 2016.

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What Is the Current Site Status?








The first phase of thermal treatment of contaminated groundwater and soil at the site was completed in 2018.  EPA used the information gained by treating about 10 percent of the contaminated area to design the larger-scale system needed to treat the remainder of the site. 

The second, and final, phase will remediate the remaining area of the site designated for thermal treatment and will occur in two stages. Site work is scheduled to start in mid-May 2020 and the treatment system would be operational in winter 2021. Currently, it is projected that it will take at least four years to complete the phase two treatment.







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