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Site Description
The Powhatan Mining Company site is the location of a former asbestos processing facility. The mill operated from approximately 1920 to 1980 primarily processing anthophyllite asbestos. Asbestos ore for the mill was mined in Maryland until about the 1940s and later brought in from several States including California, Georgia and Alabama. The site is bordered on all sides by residential properties and the residential yards to the southwest lie within feet of the former processing facility and in the path of site runoff. In 2006, the property to the east of the former mill was subdivided into residential lots for new home construction. From 2006 to 2008, the residential lots were cleared and graded and retention ponds were installed. Development ceased after only two homes were constructed.
The former processing facility is a multi-story building with a loading area on the northeast end (cement block portion) and a processing area at the southwest end (rusted metal portion). The asbestos fiber extraction process took place inside the building complex. Asbestos ore was reportedly received and first dried in the cement block portion of the complex. Further processing of the rock ore is believed to have occurred in the metal portion of the facility, a multi-level, timber-framed structure with stone foundation and corrugated metal siding. In the milling operation believed used at this facility, the asbestos ore was first crushed to a normal, even size and then dried. Fiber extraction then occured through a series of crushing operations, each followed by vacuum aspiration of the ore running on a vibrating screen. On the screen, the fibers were released from the ore and collected into a vacuum system. Fibers recovered from consecutive vibrating screens were brought to cyclone separators, and the air filtered to remove the finer, suspended fibers.
The property was brought to EPA's attention by the Maryland Dept of the Environment. After an initial assessment, a non-emergency Removal Action primarily intended to secure building openings was initiated by the OSC in a Special Bulletin dated August 11, 2009. More recent sampling data and conditions warranted a time-critical action. A time-critical Action Memorandum for the site, concurred on by HQ, was signed on June 8, 2010. In addition, a memorandum authorizing demolition and compensation to the property owner was approved by the Region and HQ on this date.
EPA will be conducting removal activities at the site in order to deconstruct the facility and remove/cover soil which may pose a threat to public health and/or the environment. During activities which will cause significant disturbance of interior dust or of outdoor soils, air samples periodically will be collected from personal sampling devices to determine if proper levels of protection are being used at the site. Additional air samples will be collected along the perimeter of the site to confirm that engineering controls are protective of the surrounding community.
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