Good morning, Ellen and Bruce,
Attached is a report documenting our third indoor air sampling event. Please note that we collected barometric pressure inside and outside of the building (at 30 min intervals), and had the laboratory analyze for naphthalene using EPA Method TO-15SIM to get lower reporting limits. The results indicate that the building is pressurized slightly above ambient, and that naphthalene is likely present at low levels below normal reporting limits. To further assess the risk to current workers in the basement (considered area of highest risk in the building), a site-specific Regional Screening Level (RSL) was calculated using the EPA’s RSL Calculator, with default values for exposure duration and frequency changed to reflect actual time spent working in the basement by these employees. The detected naphthalene was less than the calculated site-specific RSL, and we are recommending closure.
Stephen Omo, R.G.
Project Manager
503-570-9484 ext. 2 (office)
503-572-0082 (cell)
Email: smomo@bbaenv.com
BB&A ENVIRONMENTAL
Portland Office
25195 SW Parkway Ave., Suite 207
Wilsonville, OR 97070
Eugene Office
32986 Roberts Court
Coburg, OR 97408
Web address www.bbaenv.com