WTC monitoring scope update, July 2002

NYC 9/11 Public Portal Document

4. Pre-cleaning and Post-cleaning Wipe Sampling Procedures How does this section relate to Sections 3. f and g above? It looks like we are saying to monitor a set ofresidences where no clean up will occur and that is what Section 3 is sill about. Ifso, the title for Section 3 should reflect that, e.g.. Sampling OfResidences That Will Not Be Cleaned- Then Section 4 should be titled something like. Sampling Qf Residences That Will Be Cleaned..followed bya statement that the directions in Section 3 will be followed for these residences with the exception of sections f and g for which sections a and b should be substituted.

a.The Proj ect Monitor will collect pre-cleanup and post-cleanup wipe samples at 5 percent ofthe residences cleaned up to a maximum of50 units per quadrant as instructed by EPA. Units and quadrants should be defined. Why are only 5 % being sampled rather than the, as done in Section 3?- Is_this because the set ofcleaned residences is much larger than that ofthe residencgg thatwill not be cleaned? What are the criteria for selection? This sampling will consist ofdie collection of3 pre clean-up and 3 post clean-up wipe samples for dioxin, total metals and mercury (Note: a separate wipe sample is required for each parameter). Metals and mercury wipe samples will be collected in accordance with procedures specified in HUD Appendix 13.1. Dioxin wipe samples will be collected in accordance with the procedures specified in ASTMD 6661-01. Wh< are the criteria for selecting 5% of the residences?

b. The contractor shall document all the necessary information regarding sampling activities, fill out all field logs, data sheets, and chain-of-custody forms. The contractor shall use F2L for all sample and chain-of-custody documentation. Samples must be labeled and accompanied with completed chain-of-custody forms before shipping to the designated laboratory. ThelabelmustincludetheEPAProjectTrackingNumber. Sampleswill be packed, sealed and hand-delivered for analysis to EMSL laboratories at: 307 W. 38* St., New York, New York 212-290-0051. Metals samples will be analyzed using EPA Method SW-8466010B. Mercury samples will be analyzed using EPA Method SW-846 7471A.

Deliverables

The Project Monitor shall review all deliverables prior to submission to EPA. The review shall assure that each deliverable is accurate and complete, technically sound, and free ofclerical errors.

The Project Monitor shall complete chain-of-custody forms and record the number of wipe samples, EPA Project Tracking Numbers, the laboratory address, date, and sample IDs in an agreed upon electronic format or website approved by EPA within 24 hours of activity.

5. The Monitoring contractor shall evaluate all HVAC systems in all residential buildings where cleaning will take place to determine ifthese systems have been impacted by dust or debris from the collapse ofthe World Trade Cento" and ifthese systems require cleaning. This evaluation should occur prior to any of the residence. In cases where cleaning is requested for a whole building, the building’s

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