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Hazardous Waste Cleanup: Evoqua Water Technologies LLC (Formerly: Siemans Industry Incorporated) in Darlington, Pennsylvania

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Cleanup Status

On April 27,2012, The U.S. Environmental Protection Agency (EPA) has determined that corrective action is complete without controls at the Siemens Water Technologies Corp. (formerly Envirotrol Inc.) Darlington facility. The facility is currently owned by Evoqua Water Technologies.

On June 27, 1996, EPA conducted a comprehensive sampling event at the facility.  The goal for the sampling was to gather data in response to allegations by area residents that dust emissions from the facility were migrating offsite.  EPA sampled spent carbon being processed in the kilns and scrubber water from the company’s air pollution control system.  Air samples were taken at several outdoor locations as well as inside the main processing building.  Dust samples were also taken from locations on the property, from the adjacent Grief Brothers and Star Brite facilities, and from five residential properties.  Carbon and scrubber water samples were analyzed to identify elements that were characteristic of the carbon being handled at the facility.  The air and dust samples were analyzed for the same characteristic elements and compared to the carbon and scrubber water samples.  EPA analysis found that none of the dust accumulations at the neighboring businesses and residential properties could be directly attributed to the management of spent carbon at the facility.  The only environmental samples that “matched” carbon samples taken from the facility were dust samples taken from trailers parked next to the roll up doors of the facility’s main processing building.  No dust samples taken from off-site locations, including those taken from private homes and the Grif Brothers and Star Brite facilities, “matched” the spent carbon samples.  EPA concluded for the sampling results that the operations at the facility have not adversely impacted the environment or the surrounding community.  Furthermore, EPA has determined that both Environmental Indicators for human exposures and groundwater migration have been met. 

On March 15, 1999, EPA issued a 3004(u) Permit to Siemens Water Technologies to operate a hazardous waste carbon regeneration facility with associated hazardous waste storage and handling.   Compliance with this permit and the Pennsylvania Department of Environmental Protection (PADEP) Air Quality Permit satisfies the requirements of Resource Conservation and Recovery Act (RCRA) Corrective Section 3004 (u) and 3005 (c) (3). 

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Site Description

Interactive Map of Evoqua Water Technologies LLC, Darlington, Pennsylvania

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The Siemens facility is located at 118 Park Road, Darlington, Pennsylvania 16115.  The Facility is approximately 20 acres and consists of a 100,000 square feet operation building.  Siemens regenerates spent carbon through thermal treatment.  The Facility treats approximately 50,000 pounds of spent carbon per day.  

Siemens is a permitted facility.  The permit sets forth the conditions and requirements for the management of hazardous wastes and the operations of the kilns to regenerate spent carbon via thermal treatment.  The regeneration process consists of placing the spent carbon into a kiln at various temperatures until the volatiles are driven off.  The kiln is an oxygen free environment that prevents the carbon from burning and being destroyed.  From the kiln the regenerated carbon is sent into a cooling screw where it is cooled by noncontact water that is sprayed on the exterior of the cooling screw.  When the regenerated carbon leaves the cooling screw it is packaged for shipment.

The acid gases by-products from the thermal treatment are diverted to an after burner where residual fly ash in the gases is further incinerated to destroy any remaining heavy organics.  The gases are then sent to a wet scrubber where particulates and pollutants are removed.  A final stage through a carbon packed column removes the acid gas and produces clean steam, which is discharged to the atmosphere.  Waste water collected from the wet scrubber is disposed offsite as hazardous wastes. 

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Contaminants at this Facility

Contaminants at the facility primarily include waste oils from cutting, milling, and de-burring operations. Several waste oil releases from the facility to Walnut Bottom Run have occurred in the past; however, many of the operations from which these releases occurred (sumps, troughs, planers, and an underground storage tank) were cleaned and removed in the 1990s. Therefore, potential risks to ecological receptors in Walnut Bottom Run have been minimized, and risk to potential human receptors is likely negligible.

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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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