2002 E-Mail Sent M. Gilsenan

NYC 9/11 Public Portal Document

d. Common spaces will be sampled using modified aggressive techniques (20 inch fans). For small spaces, less than 160 square feet, 3 samples will be collected. For large spaces greater than 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 from obstructions. The sampling cassette must be placed on a tripod directed downward at a 45 degree angle and not taped to existing surfaces. e. Air samples shall be collected in accordance with the procedures §^^ified in NIOSH Method 7400 for PCM and 7402 for TEM. Air sampling pumps need to be monitored to ensure pumps are not clogging by monitoring flow rates, the minimum sample volume required is 3600 liters. f. The contractor shall document all the pessary information, re ; sampling activities, fill out all field logs, data s|iits, and chain-of-ci® y W. The contractor shall use F2L for all sample anc^^^i^l^ustody documi IT Samples must be labeled and accompanied with completed chain of custody forms before shipping to the designated laboratory. The label must include the EPA Project Tracking Number. Samples will be packed, sealcdjgSd shipped to EPA Contract Laboratory for analysis. g- AU 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 electronicaily in an EPAL^pproved format within 24 hours. Information on sampling activities (date, sample ID) shall be provided to EPA, via the website, within 24 hours of comp^on of sampling.

•eliverables ■

Tl Monitor shall review all deliverables prior to submission to EPA. The review shall each dehyOBiBiS, accurate and complete, technically sound, and tree of clerical erroi

The Project ft Hbhall record equipment used to collect the sample (leaf blower, fan, etc.) and size of sp. J daily b the field notebook. In addition, date, start and completion dates for tbb cleaning,« nple media, flow media type, flow rates (start/final, flow rate (average), time (start/finish). Total elapsed time (min), calculated sample volume (L), pump fault, weather, units, QC sample^ofblank) sampling dates and sample identification numbers sample IDs, complete chain of custody, EPA Project Tracking Numbers and laboratory address shall be entered into j^greed upon electronic format or website approved by EPA within 24 hours

•6: Waning 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 of 50 units per quadrant as instructed by EPA. This sampling will consist of the collection of 3 pre clean-up and 3 post clean-up wipe samples for total metals and mercury (Note: a separate wipe sample is require for

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