Consultant letter on cleanup and air monitoring, 1 Peck Slip,

NYC 9/11 Public Portal Document

Mr. Nick DeCarlo, CHMM, CPEA Disaster Response and Recovery Peck Slip Station October 3, 2001

Following the O&M clean up, URS collected air samples on each floor of the facility for subsequent analysis for asbestos, lead, silica, and nuisance dust. The objective of the monitoring program was to determine if there were any exceedances of the U.S. Occupational Safety and Health Administration (OSHA) Permissible Exposure Limits (PEL) for airborne asbestos, lead, silica, or nuisance dust.

All air sampling pumps were calibrated before and after each use. The average flow rate and total sample time for each sample were used to calculate the total volume of the air passing through the filter media, and were used in the subsequent concentration calculations.

Asbestos

Airborne asbestos samples were collected throughout the facility in accordance with National Institute for Occupational Safety and Health (NIOSH) Method 7402. The samples were analyzed by Scientific Laboratories (SciLab). SciLab is certified under the New York State Environmental Laboratory Approval Program (ELAP) to conduct airborne asbestos analysis by TEM. All airborne asbestos samples were well below the post-abatement action level of 0.01 asbestos structures per cubic centimeter of air sampled (s/cc). See Attachment A for the field and laboratory report.

Lead

NIOSH Method 7082 was used by URS for the collection and analysis of airborne lead samples. This method uses atomic absorption spectrophotometry (AAS) to identify airborne lead that had been collected on the sample filter. Lead in air samples were analyzed by ATC Associates in New York City, an American Industrial Hygiene Association (AIHA)-accredited laboratory. The lead in air concentrations ranged from <1.7 to 7.8 micrograms per cubic centimeter (µg/m3), which is well below the Occupational Safety and Health Administration (OSHA) Action Level of 30 µg/m3 and Permissible Exposure Limit (PEL) of 50 1g/m3 of air sampled. See Attachment B for the field data and laboratory report.

Silica and Nuisance Dust

URS performed air monitoring for silica and nuisance dust based on NIOSH Method 7500. Silica/nuisance dust samples were analyzed by EMSL Analytical of Westmont, New Jersey, an AIHA-accredited laboratory. Total silica concentration readings were less than the detection limit of the analytical method, thus indicating that silica was not detected. Thus, the OSHA PEL for total silica dust was not approached or exceeded. Total nuisance dust ranged from 0.0000 to 0.3556 ma/m3, well below the OSHA PEL of 5 mg/m3. See Attachment C for the field data and laboratory report.

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