Analytical results to FEMA, 114 [address], July 2003

NYC 9/11 Public Portal Document

Asbestos Data

Based on the results that were received, it appears that eleven wipe samples and sixteen microvacuum samples were collected by Ambient Group Inc. and analyzed by EMSL Analytical Inc. for asbestos. An additional wipe sample and two microvacuum samples were submitted as blanks. A summary of the results is presented below.

Location Matrix Sample Minimum Average Maximum Size Cone. Cone. Cone. (s/cm^) (s/cm^) (s/em^) Ail locutions MB! _______________ Below floor Wipe I 11,681 11,681

Wall Tracking Wipe 9 8,056 726,108 4,327,650

Below Light Switch Wipe 1 8,652 8,652

Blank Wipe 1 2,164 2,164

■ ills \ Below Floor Microvacuum 10 40,192 369,830 1,115,570

Wall Tracking Microvacuum 1 15,058 15,058

I-beam Micro vacuum 2 7,636 7,636 8,038 (ND)

Column Micro vacuum 1 8,038 (ND) 8,038 (ND)

Pipe Shaft Microvacuum 71,592 71,592

Front Office Microvacuum 1 743,552 743,552

Blank Microvacuum 2 803 803

ND= asbestos not detected

The interpretation of these results is constrained by the scientific uncertainty regarding the potential for the measured concentrations in settled dust to become airborne. There are no standards currently available for assessing potential health consequences from asbestos through the evaluation of wipe or microvacuum samples. A scientific peer review panel (World Trade Center October 21- 22,2002 Peer Review Meeting Notes. Available at www.tera.org.) recently evaluated the technical soundness of estimating airborne asbestos concentration as a function of asbestos concentration in settled dust for the purpose of setting health-based benchmarks. The panel recommended against such an approach based on the significant uncertainty associated with the numerous factors (such as activity patterns, sample location, surface characteristics, air exchange rates and room

2

NYC-WTC_000160457