Environmental memo correspondence, 225 Broadway, Sept 2001

NYC 9/11 Public Portal Document 11/02/01 FRI 1515 FAX 212 233 5367 Witkoff 233 Bldg Mgmt Of (1002

9212 671 4725 the iittoff Group 10/16/01 13:03 P.002/085

• dvanced Environm.entaI Corp.

October 12, 2001

Mr. Craig Murphy Director of Project Development The WitkoffGGroup 220 East 42' Street New Ycrb, NY 10017

Re: Asbestos Air Monitoring, Various Areas, 233 Broadway, New Yorky NY D Murpkv

On October 11, 2001, Advatwced Falvimnmental Corp. performed air monitoring at the above Ioeadon. Samples were collected on floors specified by bw'lding management to document the asbestos fiber concentration levels of the ambient air from represeata±ive areas of the building.

Six (6) samples were collected sud analyzed using the Transmission 1lectron Microscopy CIEM) method according to the EPA AURA protocol. TEM with energy dispetsfvc X-ray analysis is an method that enables a fibers chemical composition to be Identified and thereby overcominganalytical the non- specificity of PCM analysis. This fiber specific protacot is generally utilized to determine cictu air following a "lar$r'4 14 baqient project.TF.M pample analysis detects filter loads (the number of structures detected per squ ae miilireetcr of collection media su:fmce) whit s, if less than or equal to EPA .AHERA release criteria of 70 slructures per sque millimeter (s/mmz), determine whether or not the area is safe for cY• The TEM samples were collected in the lobby area, floors 5,12,16, and 29. The sarr lee and the results can be found in Appendix A. Listed is the sample identification number, area analyzed, sample volume, shuotmc annuls, analytical sensitivity, and the concentmtloa of asbestos. As a review of Appendix A shows, no asbestos structures were detected on any samples collected. In conclusion, the TEM sample data show acceptable concentaatieas of fibrous materials in the ambient

If you have any questions or need furtber clarifiwxioa on air sampling methodology, please can me.

Sincerely, e, € Edward Narnath 4 1135.005

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