On November 9, 2007, the Massachusetts Department of Environmental Protection (MassDEP) responded to a United States Postal Service employee’s report to the local authorities that he observed beads resembling a “mercury like” substance on the street and the sidewalk directly in front of the Site building, and also on the walkway next to the building, located at 716 Broadway Street in Fall River, Massachusetts. The building on the Site is a three story wood frame, built in approximately early 1900s. The MassDEP responded, and verified through a Jerome mercury vapor analyzer that the substance was elemental liquid mercury. The MassDEP also conducted additional air sampling inside the house and detected elevated levels of mercury vapors that were well above background levels of 0 nanograms per cubic meter (ng/m³). In response, MassDEP hired a cleanup contractor (TMC Services, Inc.) and recovered the gross visible mercury from the Site’s building interior and exterior. During that time, the MassDEP contacted EPA and requested air monitoring assistance to assess the extent of mercury contamination.
On November 9, 2007, EPA and its Superfund Technical Assessment and Response Team (START) contractor responded to the incident scene, performed a visual inspection of the spill areas, and conducted air monitoring with the Lumex Model RA915 and Jerome Model 431-X mercury vapor analyzers. The results from the air sampling activities revealed that elemental mercury and mercury vapors existed throughout the building at levels exceeding the Agency for Toxic Substances and Disease Registry (ATSDR) health based risk standard of 300 ng/m³. The levels in the 1st floor (occupied by Mr. Thomas Gorton and Ms. Nicolle Medeiros/current owners) ranged from 10,000 up to 50,000 ng/m³. The 2nd floor (occupied by an elderly woman) levels ranged from 17,000 to 30,000 ng/m³. The 3rd floor (unoccupied and used for storage) ranged from 15,000 to 16,000 ng/m³. Air concentrations in the basement where the mercury beads were originally stored, and removed by the MassDEP contractor, ranged from 12,000 to 50,000 ng/m³. The air sampling readings outside the building were at normal background levels.
Present at the Site during the air sampling activities were: Thomas Gorton (current property co-owner), Andy Jones (MassDEP), and John Staskiewicz (Fall River Department of Health). When asked by MassDEP and EPA if he was aware of the mercury situation, Mr. Gorton stated that he was unaware of any mercury in the building, or that his actions had caused mercury to spill in the basement and other areas. He also stated that he purchased the property in August 2007, and has been doing renovation work ever since. He also stated that while cleaning the basement, he moved some of the old trash (electrical equipment, etc.) left by the previous owner to the street curbside for trash pickup and recycling. The last trash and recycling pick-up date in the immediate area occurred on Monday, November 5, 2007.
After review of the air sampling results, MassDEP, EPA and the Fall River Department of Health (FRDOH) agreed that the high levels of mercury were a significant risk to human health. This decision was made by comparing the building’s mercury levels to the action numbers that have been developed by EPA in consultation with the ATSDR, June 12, 2006, Region New England Mercury Response Guide Outline. In turn, the responding agencies recommended to Mr. Gorton and to the 2nd floor tenant that they seek alternative lodging until the building is re-assessed and determined safe for re-occupancy. Mr. Gorton and the 2nd floor tenant agreed to the alternate lodging request. In addition, the responding agencies suggested to Mr. Gorton that he should attempt to aerate the building by placing air fans in as many windows possible to aerate the building. It was decided by the responding agencies to allow the building to cross ventilate for 24 hours and reconvene the next day to re-evaluate the conditions.
On November 10, 2007, EPA, MassDEP, and FRDOH agencies returned to the Site. EPA and START conducted air monitoring inside and outside of the building with the Lumex and Jerome mercury vapor analyzers. The interior readings indicated that elevated levels of mercury were still present, while the outdoor readings around the property remained at normal background levels. However, the interior readings, possibly from the overnight ventilation activities, were considerably lower than the readings taken on November 9, 2007. The levels on the 1st floor ranged from 1,000 to 12,000 ng/m³. The 2nd floor ranged from 700 to 3,000 ng/m³. The 3rd floor ranged from 2,100 to 3,600 ng/m³. The highest reading in the basement was 490,000 ng/m³ (after agitation of the spill area). Elevated levels up to 35,000 ng/m³ were also detected in the side porch of the building. The responding agencies informed Mr. Gorton and the 2nd floor tenant of the mercury levels. The air sampling readings outside the building were at normal background levels. The agencies decided to demobilize from the Site and re-evaluate the Site conditions after the weekend. The responding agencies also requested to Mr Gorton that he leave the windows open over the week-end to continue the aeration process.
On November 13, 2007, EPA, MassDEP, and FRDOH returned to the Site to determine whether elevated levels of mercury were still present. EPA and START conducted air monitoring inside and outside of the building with the Lumex and Jerome mercury vapor analyzers. The air sampling revealed that mercury levels were non-detectable outside the building, but still existed at elevated levels throughout the interior of building and the porch. EPA, MassDEP, and FRDOH discussed the results and the following decisions were made: 1) the City of Fall River Department of Health found that mercury levels exceeded limits for domestic habitation and formally ordered Mr. Gorton to evacuate the entire premises until further notice, pending corrective actions, and 2) MassDEP requested EPA’s assistance to conduct a time critical removal action to address the mercury release.
On November 14, 2007, the responding agencies returned to Site. EPA and the MassDEP informed Mr. Gorton and the 2nd floor tenant of the above mentioned decisions and future cleanup actions that would be taken by EPA. Mr. Gorton agreed to temporarily re-locate to his parents home and the 2nd floor tenant agreed re-locate to the building across the street. In addition EPA and START conducted another round of air sampling. The results again ranged from non detectable (outside) to more than 50,000 ng/m³(inside).
