NYC-WTC_000231403

NYC 9/11 Public Portal Document . -T.™ fc--

104 East 25th Street New York, New York 10010 www.atc- envire .com 212.353.3230 Fax 212.353.8306 associates I H c .

October 11, 2001 pj ALC Environmental / 115 W. 30th Street : New York, NY 10001 i Attn: Mr. Joshua Sarett

Re: Report of TEM Analysis i Dear Mr. Sarett:

Following are the results of transmission electron microscopy (tem) analysis of air samples from our Group No. 5SS1.

Client: Gateway Plata Mngt. Corp, Project Name: Building 400 at Gateway Plata - 375 South End Ave. : Location: Various Sites Samples received: 10/10/01 ( These results will confirm and document the data transmitted today ; to you. .The analyses were performed in strict conformance with the j methodology of the AHERA Final Rule {CFR October 30, 13371 for f clearance of abatement sites. As indicated on the attached Summary I Reaulte sheet, less than 70 asbestos structures per mm* was detected in all of the twenty-five samples submitted from the site. Results reported as Struct/cc are a function of air volume collected in the field and are, as such, not verifiable by this laboratory. Thia report may be reproduced only in its entirety and r not without prior permiaaion of this laboratory. If the post­ abatement inside samples pass, the response action may be considered to have been completed. The analyses were supervised by Dr. Michael A. Gbrycki, Director of Electron Microscopy, I We are pleased to note that our tem lab has received /ull I accreditation from NVLAP, as is currently required for recognized L analysis of TEM air samples for AHERA projects, and also approval s; under the NY State DOH ELAP program. These analyses were performed L by ATC d/b/a ATC Associates Inc, Please contact me regarding any questions relating to these materials.

K Very truly yours.

I Michael A. Gorycki, Ph.D. I Director of Electron Microscopy

03563 CITY_21MC100_008879979

NYC-WTC_000231413