Letter enclosing air monitoring report, 75 Maiden Lane, Mar 2002

NYC 9/11 Public Portal Document

03/06/2002 08:03 2125450757 ADVANCED ENVIRONMENT PAGE 02

dvanced Environmental Corp.

February 21,2002

• Mr. Robert Spatz Recovery Physical Therapy 79 Maiden Lane New York, NY 10038

Re: Air Monitoring, Basement Therapy Room, 79 Maiden Lane, New York, NY

Dear Mr. Spatz: monitoring at the above On February 12, 2002, Advanced Environmental Corp. performed limited air location. Samples were collected to document the asbestos, respirable dust, and priority pollutant metal concentrations of the ambient air from the basement therapy room at 79 Maiden Lane, New York, NY. to comply with OHSA permissible exposure Please be advised that this information is not intended monitoring requirements or requirements for clean air following asbestos abatement work. We reference the OSHA standards and abatement release criteria to merely give information for comparative reasons.

Asbestos (TEM) method One (1) sample was collected and analyzed using the Transmission Electron Microscopy according to the EPA AFIERA protocol. TEM with energy dispersive X-ray analysis is an analytical method that enables a fibers chemical composition to be identified, in this case asbestos. This fiber specific protocol is generally utilized to determine clean air following a "large" abatement project. TEM structures detected per square millimeter of collection sample analysis detects filter loads (the number of square media surface) which, if less than or equal to EPA-AHERA release criteria of 70 structures per millimeter (s/nzrnx), determine whether or not the area is safe for re-occupancy.

The sample was collected on a 0.4-µm pore size, 25 mm mixed cellulose ester filter/support pad cassette, with a 10 mm electrostatic cowl. High volume air pumps were used to draw air through the filter media. Flow rates were measured with a calibrated rotameter, before and after sampling to ensure an accurate volumetric reading.

The TEM sample was collected from basement therapy room. The sample results can be found in Appendix A. Listed is the sample identification number, area analyzed, sample volume, structure counts, analytical sensitivity, and the concentration of asbestos. As a review of Appendix A shows, no asbestos structures were detected on any samples collected.

Respirable Dust (Particulates {lnsoluable} Not Otherwise Classified [PNOCs]

One Respirable Dust air sample was collected and analyzed according to the National Institute of Occupational Safety and Health (NIOSH) 5001600 method. The sample was collected on a 5-µm pore size pre-weighted PVC membrane filter using a 37 millimeter cassette. A low flow volume personal air pump was used to draw air through the filter media. Flow rates were measured with a Mini Buck calibrator model M-30, before and after sampling to ensure an accurate volumetric reading.

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