On or about Monday August 10th, the removal of a mercury-containing device along with worthless debris from a science lab at Brenau University (Brenau) resulted in a release of mercury to the floor and along the route to the garbage pen at the NW corner of the building. EQ conducted the initial stabilization of much of the visible mercury.
During the morning of Monday August 17, 2009, John Keller of Brenau contacted OSC Jardine requesting that EPA conduct the appropriate removal action at the Science Building at 615 Washington Street. Mr. Keller identified timeliness and availability of resources as essential to the response since classes are scheduled to begin Monday August 24th.
During this period EPA closed and heated the inside of the building to begin closure sampling. After several hours of sampling EPA determined that additional work would be necessary to attain the guidance closure concentrations for mercury in an industrial workplace. EPA requested a consult from ATSDR who arrived on scene Wednesday afternoon. ATSDR recommended some tactics and provided health based site-specific guidance based on the expected frequency and duration of exposures to students and staff in the Science Building.
EPA attempted to reduce vaporization from electrical conduits and cracks in the aging concrete floor in Room 22 and closet by applying caulk to seal such penetrations. During this activity, the caulk displaced free mercury from void locations and caused it to drip into Room 12 (directly below Room 22) and its associated closet. EPA immediately collected the mercury beads from Room 12 and applied several technologies to clean residual contamination.
Other work accomplished during this reporting period includes removing porous materials and non-porous property (scales, test tube holders, lab rods and clamps, etc) that off gassed mercury above 10,000 ng/m3. This property was either staged in the roll off box or given to Brenau for appraisal. Brenau intends to temporarily stage the property in the maintenance yard pending a decision.
EPA also applied cleaning solution to the parking area adjacent to the garbage pen, solidified captured solutions from various washing operations, stabilized mercury captured from vacuuming operations, sampled and delivered to lab various waste stream samples, continued with heating and venting of rooms and corridors, and staged all remaining removal-derived waste in the 20 cu yd roll off.
EPA allowed the air within the building to again become stagnant and warm (75 to 85 degrees F) and conducted closure sampling over an eight hour period. Mercury concentrations in all rooms and closets, except the R22 closet, were measured to be below the guidance closure number of 3,000 ng/m3.
The R22 closet reached nearly 9,000 ng/m3. EPA installed two box fans in the closet window. Brenau has agreed to restrict access to the room to pregnant students and staff, and maintain the venting for 30 days. EPA will return to measure the mercury vapor concentrations in 30 days.
On Friday EPA intends to conduct a temporary demobilization by removing all personnel and equipment, except the two box fans.
None
|
