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Hazardous Waste Cleanup: Westlake Plastics Company Incorporated in Lenn, Pennsylvania

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Cleanup Status

EPA sets national goals to measure progress toward meeting the nation’s major environmental goals. For Corrective Action, EPA evaluates two key environmental indicators for each facility: (1) current human exposures under control and (2) migration of contaminated groundwater under control.  On February 29, 2012, Michael Jr. Baker, Inc. conducted an Environmental Indicator (EI) Inspection of Westlake Plastics Company, Inc. (Westlake or Facility), on behalf of EPA. The findings of the EI Inspection are documented in an August 2012, EI Inspection Report prepared by Baker. Also presented in the EI Inspection Report is a summary of the information reviewed by Baker in preparation for the EI Inspection, including records maintained by the Pennsylvania Department of Environmental Protection (PADEP) and EPA. Based on a review of the information presented in the EI Inspection Report, EPA determined that the Facility met both environmental indicators on March 26, 2013.

On April 18, 2013, EPA announced its proposed decision of Corrective Action Complete without Controls under the Resource Conservation and Recovery Act (RCRA), as amended, for Westlake. Consistent with public participation provisions under RCRA, EPA requested comments from the public on the proposed decision as described in the March 29, 2013, Statement of Basis (SB). The commencement of a thirty (30) day public comment period was announced in the Delaware County Daily Times newspaper on April 18, 2013, and on the EPA Region 3 website. The public comment period ended on May 17, 2013.

On May 27, 2013, EPA issued its final decision for Westlake in a document entitled the Final Decision and Response to Comments (FDRTC). EPA received no comments on the proposed decision.  Consequently, EPA’s final decision is unchanged from the proposal. EPA has determined that its final decision is protective of human health and the environment and that no further corrective action or land use controls are necessary.

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Site Description

Interactive map of Westlake Plastics Company Incorporated, Lenni, PA

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Westlake is located at 490 Lenni Road in Lenni, Delaware County, Pennsylvania. The Facility is composed of two separate properties (referred to as Section No. 1 and Section No. 2), which are separated by Lenni Road, Chester Creek, and a privately owned parcel of land. Section No. 1 , the northernmost section, is located in Chester Heights Borough and consists of three parcels of land totaling approximately 8.6 acres. Section No. 1 is bordered on the south by Lenni Road, on the east by Chester Creek, and the west and north by wooded areas. Section No. 2  is located in Middletown Township and consists of two parcels of land totaling approximately 12 acres. Section No. 2 is bordered on the north by Lenni Road, on the west and south by Chester Creek, and on the east by a partially wooded/field area. The area surrounding the Facility is primarily a wooded residential area. A small number of commercial and industrial enterprises are scatter throughout, with the majority located east and south of the Facility. 

Westlake was founded in 1951 and purchased the properties that comprise Section No. 1 and Section No. 2 in 1953. Ownership of the property prior to 1953 is unknown; however, the original Facility buildings were constructed in the mid-1850s and were used as a woolen mill. Westlake is a subsidiary of Pacific World Corporation and manufactures thermoplastic and thermoset plastic products by extrusion and compression-molding methods. The products are fashioned by melting plastic pellets (raw material) and forcing the liquid plastic into molds and dies to form the desired shape, such as rods, slabs, sheets, and film. The extrusion process is performed at Section No. 1; Section No. 2 is utilized by the Facility to receive deliveries, store extruded materials prior to annealing, anneal extruded material in hot air ovens, fabricate extruded materials, and store finished products.

Historically, newly formed plastics were annealed in a bath of high temperature lubricating oil (annealing oil) or diethylene glycol to prevent brittleness and remove internal stress created during the extrusion process. Following the annealing process, the plastics were washed with mineral spirits to remove residual oil, generating a mixture of spent annealing oil and mineral spirits (i.e., petroleum naphtha) waste stream. The spent annealing oil/mineral spirit mixture was stored in 55-gallon drums and managed as an ignitable (EPA Hazardous Waste Code D001) characteristic hazardous waste. The spent annealing oil/mineral spirit mixture was reclaimed on-site through distillation to recover the mineral spirits for reuse in the Facility’s manufacturing operations. The waste annealing oil and the still bottoms generated by the distillation unit were determined to be non-hazardous and were shipped off-site for disposal. 

In 1994, large hot air ovens were installed in Section No. 2 to replace the annealing baths. As a result, the Facility became a non-generator of hazardous waste. 

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Contaminants at this Facility

No contaminants above levels of concern exist at the Facility.

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Institutional and Engineering Controls at this Facility

Institutional Controls were not required at the facility.

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Land Reuse Information at this Facility

The facility is under continued use.

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Site Responsibility at this Facility

RCRA Corrective Action activities at this facility have been conducted under the direction of EPA Region 3.

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