Chain of custody form header with redacted text for DEP

NYC 9/11 Public Portal Document mY-10-2002 16=25 P.0Q/13 BULK asbestos ANALYSIS RESULTS *■ PLM Analysis Methodology

The samples were analyzed by industry seceptsd methods in accordance wi± EPA and ELAP methods using Polarized Light Microscopy (PLM) W!t.h dispersion staining in conjunction with stereoscopical analysis. Point counts ara performed on samples regulated by these agencies. The Environmental Laboratory Approval Program fEL.AP) has determined that analysis of oon-friable organically bound rnawrials (La. floor tile, roofing, etc.) is not reliable when performed by Polarized Light Microscopy (PLM) method. Therefore, if this analysis included that of non-frlablc materials under PLM and die results were negative. ATC must add this dtsciaimer to maintain our ELAP accreditation; “Polarized light microscopy is not consistently reliable in detecting asbestos in floor coverings and similar non- friable organically bound materials. Quantitative Transmission Electron Microscopy is currently the only method that can be used to deteraiine if this material can be consider; J or treated as non-asbestos containing". Samples dial are layered and analyzed by tlic gravimetric method as composites (NESHAp, AHEILA) should be considered positive if results ore between trace and 1%, unless every layer is analyzed separately.

£PA does not regulate mixed mineral assemblage like the anthophyllite-talc intergrowth that is found in paint and caulking unless these materials contain asbesteS in an amount greater than 1%. Anthophyllite detected in paint and caulking samples might be a talc intergrowth.

ATC has (he capability of pcdbrrning TEM confirmation if so desired.

All bulk sample reports ore cheeked and reviewed two times. Unused portions of samples arc archived for Tlvec months unless client requests special handling. Tlih repon must nut be used by die client to claim product endorsement by NIST or any agency of fee U.S. government.

ATC .Associates Inc. is not responsible for sample colicction and analytical procedures not perfonned by our laboratory. This report may not be reproduced in pan without the laboratory permission.

ATC Associates will not be liable for analydcai results from Simples that are not prepared according to the standard methods (EP.A, ELAP. etc.) used by the laboratory (e.g. composite samples from different locations, samples with Insufficient volumes, straight TEM samples without gravimetric procedures, and dust samples).

Labomto^ Eoiiinment

Laboratory analysis was accomplished utilizing Olympus BH-2 Microscopes,

Quality Control

ATC Associates Inc. is accredited by NVLAP (Lab Code 11^7-00) and NY State DOH ELAP (Lab ID 1087?) for bulk and air fiber analyses. ATC participates id die Bulk Asbestos Sample Quality Assurance Programs for NVLAP and ELAP and maintains an in-house QC/QA program for bulk samples whereby 10% of all submitted samples are reanalyzed and documented ia a Quality Control Manual. ATC also participates in a quarterly round robin QC/QA program for bulk samples with several accredited laboratories throughout the United States. Current and past QC/Qa program results are available in die laboratory for inspection.

Accuracy and Precision

The phase abundances provided by point count may be considered within the limits of variability inherew ia the metliod ernployed. The sample results are accurate to within +/’5« 10 percent measured by die calibrated visual estimate method. For point counts die detecaon limit of 025% is based on one asbestos point counted over -100 non-empty points. If < 1 point counted and asbestos is detected, a trace result will be reported Trace is < 1% ACM.

The analyses were supervised by Milena Lewd, Director of Laboratory Services, who has e-xtensive e-xperienca in asbestos analysis by PLM and other methods. Please contact me regarding any questions relating to ±cse materials at 212-353-8280 Ext. 247.

^Sincerely,

'Milena B. Lowd Director of Laboratory Services

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