Air and bulk sampling results letter, Sept 2001

NYC 9/11 Public Portal Document

09/ 2812091 10:14 63158 3195 ENt+ I ROSC I ENCEONSLTAN PAGE 82

ENVIROSCIENCE CONSULTANTS, INC. 2150 SMiY'HTOWN AVENUE RONKONKOMA; NEW YORK 11779-7348 PHONE: (631) 580-3191 o FACSIMILE 0631) 580-3195

D. GALLA $ !I C. GnLQRRT, P,.D, P. Or*MOpT T.KLue,OCR- E. OETWRLER G. Nau{OMWEKOwn 28 September 2001 ~ • DRtaaDLL .•'+.• uRMECIO L•GAVARusc Mr. Kenneth Coffey, President TechCiean 242-E Route 109 Farmingdale, New York 11735 Phone: 631-454-9595 Facsimile: 631-454-9605

Subject: Air and Bulk Sampling Results for the American Stock Exchange 86 Trinity Place, 22 Themes;and 65 Broadway, New York, NY.

Dear Mr, Coffey:

Air and bulk sampling was conducted September 191 , 20th, 21', 241 2001 at the'American Stock Exchange, fib Trinity Place, 12 Thames; aad 65 Broadway. New York, NY following the explosion, fire and collapse of the World Trade Center and adjacent. buildings. It was derided to collect samples or:the following compounds based on an evaluation of the* conditions due to the explosion, fire and collapse of the World Trade Center. The substances collected included the following: asbestos(air and bulk), respirable dust (mass & particle size distribution), lead, polychlorinatedbiphenyls, poi nuclear aromatic hydrocarbons. The substances, sampling protocol, and standards employed were discussed with Dr. Nt3 rk. Maddoloni the Toxicologist assigned to the World Trade Center site by US EPA. The air and bulk sampling locations and results are reported below. Asbestos samples were collected according to New York State and U.S. EPA standards and:aoalyzed according to and analyzed U.S. EPA standards using Transmission Electron Microscopy. Other substances were collected and analyzed using the National Institutes for Occupational Safety and Health protocol.

Based or, our experience and direction from U.S. EPA and the New York State Department of Labor we recommend that those samples that met the U.S. EPA AI-ILRA clearance criteria'-of 70 structures/square millimeter are cousidered'ac oeptable and are considered safe for reoccupancy. However,-a. U.S. Occupational Safety and. Health Administration officer informed legal counsel for the American Stock Excbange that the Permissible Exposure Limit (PEL)*should be applied here. ltwas requested that the results determined using the U.S. AHERA regulations be converted to OSHA sty!e results. The U.S. AHERA regulations were developed to protect all. children, faculty, and staff in schools from asbestos exposure. The two different methodologies, U.S. EPA AHERA methodology, and OSHA used methodology differ from the beginning of the protocol. The U.S. EPA uses 70 structures per square millimeter (s/m,n') as the value considered safe for school reoccupancy by children, faculty, and staff after asbestos abaement. The AHERA protocol uses an electron microscope with a magnification of up to 200,000 times. The NIOSH method may use a phase contrast Iight microscope with a magnification of up to 400 tithes or an electron microscope.. AHE1LA'allows a Clark filter to have up to 70 structures per square millimeter. Structures are fibers, clusters, bundle:, and matrixes that contain asbestos fibers greater than. 0.5 micrometers in length. if the average work area samples are found to have less than the 70 simrn' no further action is required. If tine samples are round to be greater than 70 s/mm2 then the asbestos air concentration outside-the work area is compared with the work area air concentration and subjected to a Z-Test statistical technique or the work area may be re-cleaned and the air re-sampled. The fil.tor concentration is multiplied by the filter area and divided by the air volume sampled (in cubic ENVIRONMENTAL & INDUSTRIAL HYGIENE COMSULTANTS www.ENVIROMEALTH.ORG

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