On 9/22/14, MDCH filed an NRC Report (# 1096105), indicating that a furnace repair technician had identified a mercury spill from a switch on the furnace while completing a service call. The County Health Department screened the site with a Lumex, and reported ambient mercury levels of up to 50,000 (nanograms per cubic meter) ng/m3 near the furnace and 34,000 ng/m3 in the basement. After opening windows and ventilating the house, levels were generally reduced to less than 1,000 ng/m3. MDCH and the County Health Department  requested EPA assistance to address the situation.

The health effects of mercury are detailed by the ATSDR as follows:

The nervous system is very sensitive to all forms of mercury. Exposure to high levels of metallic, inorganic, or organic mercury can permanently damage the brain, kidneys, and developing fetus. Effects on brain functioning may result in irritability, shyness, tremors, changes in vision or hearing, and memory problems. Short-term exposure to high levels of metallic mercury vapors may cause effects including lung damage, nausea, vomiting, diarrhea, increases in blood pressure or heart rate, skin rashes, and eye irritation.

EPA mobilized to the site at approximately 5:00 PM on 9/22/14 and met with the County Health Department representative, and later with the homeowner.  The homeowner requested that we return the next morning to conduct monitoring and cleanup work. The homeowner planned to stay in the home overnight, with the windows open to maintain ventilation. EPA and START arrived on site at 8:00 AM on 9/23/14. The team closed windows and screened all rooms in the house with the Lumex. Mercury vapor concentrations were below the acceptable concentrations for most sensitive people  (less than 1,000 ng/m3) in the breathing zone in all areas of the house except right near the furnace. Mercury vapors were roughly 2,000 ng/m3 there. Visible beads of mercury were present in the furnace. As these conditions presented an imminent and substantial endangerment to public health, welfare, or the environment, ERRS was mobilized and a removal action was initiated at the site. 

Planned response activities on-site include:

a)      Assessing the site;

b) Securing, staging characterizing spilled mercury and mercury contaminated waste;

c)     Consolidating and packaging all materials containing hazardous substances, pollutants and contaminants for transportation and off-site disposal; and

d)      Transporting and disposing of all characterized or identified hazardous substances, pollutants, wastes, or contaminants that pose a substantial threat of release at a Resource Conservation and Recovery Act/CERCLA-approved disposal facility in accordance with  EPA’s Off-site Rule (40 C.F.R. § 300.440).