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NYC 9/11 Public Portal Document

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EMSL Analytical, Inc. 107 Haddon Ave., Westmont, NJ 08108

EMSk Order 10:040305286 Attn: Andrew/ M.N. Khan Customer ID; JLCCSO JLC Environmental Consultants, Inc. Customer PO: 200 Park Ave South, Suite 1001 Date Received: ' 04/05/03 12:23 AM New York, NY 10003 Fax: 212^20-6092 EMSL Order 040305286 Project: #03-2744/NYCDEP—114 Liberty ST EMSL Project ID: Report Date: 04/14/03 Date Analyzed; 04/14/03

Silica, Crystalline Analysis Performed X-Ray Diffraction (XRD) Modified NIOSH Method 7500, Issue 3,1/15/98

1 Respirable Dust Airborne Silica Sample Sample Silica SUica .% Analytical Sample ED Identification Particle Volume Weight Cone. Weight Cone. Silica Sensitivity ID (L) (tng) (mg/m’) (mg) (mg/m^ (nn^m^

MB13687-1 12THFLR SOUTH (Juartz 408 <0.002 N/A <0.0045 <0.0110 N/A 0.0110 MB 13687-2 IITHFLR DINING Quartz 408 <0.002 N/A 0.0090 0.0221 N/A 0.0110 MB13687-3 lOTHFLR DINING Quartz 408 0.601 1.4730 0.0080 0.0196 1.3 0.0110 MB 13687-4 9THFLR DINING Qusrtz 408 0.014 0.0343 0.0090 0.0221 64.3 0.0110 MD13687-5 8TII rut DININO QuaiU 408 <0.002 N/A <0.0045 <0.0110 N/A 0.0110 MB13687-6 7THFLR DINING Quartz 408 _0^ 0.0245 <0.0045 <0.0110 45.0 0.0110 MB13687-7 6THFLR DINING Quartz 408 0.090 0.2206 <0.0045 <0.0110 5.0 0.0110 MB13687-8 STH FLR DINING Quartz 408 <0.002 N/A <0.0045 <0.0110 N/A 0.0110 4THFLR MBl 3687-9 KITCHEN Quartz 408 0.115 0.2819 <0.0045 <0.0110 3.9 0.0110

Disclaimer: The laboratory can only verify the concentration of silica on the filter and not the final concentration due to data obtained by non-laboratory personnel. In the absence of a bulk dust sample, neither the specific forms of crystalline silica nor the interfering specif can be fully determined. Hence, the amount for each phase, if anticipated, will be analyzed based on primary, secondary, and/or tertiary peak data with comparison to calibration curves of known standards. It should be noted that air samples are meant for only quanti^dng silica (or a mineral phase) which must first be identified from a bulk dust sanqsle. “<” means less than the stated value. The lowest reportable value is equivalent to the Analytical Sensitivity that is calculated from die lowest reproducible amount of specific mineral detectable by the instrument.

Anant Samudra, Ph.D. Analyst Stephen Siegel, CIH- lHab Manager Or other approved signatory AJHA Accredited - Laboratory ID #100194 Page 1 of3

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