2002 E-Mail Sent M. Gilsenan

NYC 9/11 Public Portal Document

sampling will be conducted. Residents shall not be present in their apartment during aggressive air sampling activities. 1. Before beginning aggressive air sampling, forced air equipment (such as a 1 horsepower electric leafblower) shall be used to direct exhaust air against walls, ceilings, floors and other surfaces. When directing the exhaust, caution shall be taken to minimize disturbance and potential damage to fiimishings and personal belongings. ii. For modified aggressive air sampling forced air equipment shall not be employed. iii. All other procedures are identical for aggressive and modified aggressive air sampling. b. One 20-inch fan shall be installed per 10,000 cubic feet ofroom space and run at low speed. The fan shall operate continuously throughout sampling and shall not be turned off until sampling is completed. c. For studio apartments 3 samples shall be collected. For 1-bedroom apartments and above 5 samples shall be collected. Sampling equipment shall be placed in living areas and away from obstructions. The sampling cassette must be placed on a tripod and not taped to existing surfaces. d. Common spaces will be sampled using modified aggresive techniques (20 inch fens). For small spaces, less than 260 linear feet and 160 square feet, 3 samples will be collected. For large spaces greater than 260 linear feet or 160 square feet and less than 25,000 square feet 5 samples will be collected. For spaces greater than 25,000 square feet, 1 sample will be collected for each 5,000 square feet. Sampling equipment shall be placed away fiom obstructions. The sampling cassette must be placed on a tripod and not taped to existing surfaces. e. Asbestos air samples shall be collected in accordance with the procedures specified in NIOSH Method 7400. Air sampling pumps will be operated at 10 liters per minute for eight (8) hours to achieve. To achieve minimum volume requirement of4800 liters. f. Samples must be labeled and accompanied with completed chain ofcustody forms before shipping to the designated laboratory. The label must include the EPA Project Tracking Number. Samples will be packed, sealed and shipped to USEPA Contract Laboratory for analysis. g- All information must be maintained using the secure EPA website(url, user name and password to be provided by EPA). Dates for monitoring and/or cleaning shall be provided to EPA electronically in an EPA approved format within 24 hours. Information on sampling activities (date, sample ID) will beprovided to EPA, via the website, within 24 hours ofcompletion ofanalysis.

16. Pre-cleaning and Post-cleaning Wipe Sampling Procedures

a. The Project Monitor will collect pre and post-cleanup wipe samples at 5 percent ofthe residences cleaned up to a maximum of50 units per quadrant. This sampling will consist

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