NYC 9/11 Public Portal Document
107Haddon Avenue
EMSL Analytical,Inc.- Westmont,NJ.08108
(856)858-4800
10/2/01
Attention: Chris Gerber
URS
200 Orchard Ridge Drive
Suite 101
Gaithersburg, M. 20878
Project: #i89FUSPS035/ Peck Slip Station
Ref. Number: 360100272
Silica Analysis Performed by
X-Ray Diffraction (XRD)
Method NIOSH 7500
Nuisance Dust Airborne Silica
Sample ID Identification Particle ID Volume
- -
Sample
Weight
I.
Sample
P
Cone.
Silica
Weight
Silica
Conc.
%
Silica
Analytical
Sensitivity
Quartz 1000 0.190 0.1900 <0.004 <0.0200 N/A 0.0200
2P1S1 <0.0160 N/A 0.0160
Quartz 1250 0.270 0.2160 <0.004
2P2S2 <0.0167 N/A 0.0167
Quartz 1200 0.150 0.1250 <0.004
2P3S3 <0.004 <0.0156 WA 0.0154
Quartz 1300 0.000 0.0000
2P4S4 <0.004 <0.0154 N/A 0.0154
Quartz 1300 0.200 0.1538
2P5S5
0.008 mg Quartz 0.008
Std. U3
Bulk Analysis: Sample ID Sample Description Silica Forms Identified
Bulk Not Submitted
M. Vargas & JiNewton 28 September, 2001
Analyst Date of Analysis
Disclaimer: The laboratory can Duly verify the conccntration ofsilica on the filter and not the final eoncentnrtion due to data obtained by
non-laboratory personnel. In the absence ofa bulk dust sample, the spooific form of crystall ne silica can not 6e determined.
Bence, alpha-quartz the most prevalent form ofcrystalline silica, will be assumed.
NYC-WTC 000120341
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