NYC-WTC_000188110

NYC 9/11 Public Portal Document

RJ LeeGroup^ Inc. 350 Hochberg Road Monroeville, PA 15146 Voice 721/325-1775 Fax 724/733-1799

LABORATORY REPORT

Emteque REPORT DATE October 19,2001 505 Sth Avenue, Suite 900 SAMPLES RECEIVED October 15, 2001 New York, NY 10018 RJ LEE GROUP JOB NO. XRH110131 ATTENTION: Mr. NeU Feldscher CLIENT JOB NO. 010496 90 Church St. TELEPHONE: (212) 631 - 9000 PURCHASE ORDER NO. N/A Table 1 of 3

ANALYSIS: Bulk Analysis Of Crystalline Free Silica METHODS: X - ray Diffraction

A portion of each bulk sample was ground to a fine powder, mixed with calcium fluoride (CaF,) as an internal standard, ground further, and backloaded into a standard XRD holder. The samples were then scaimed using standard run parameters on a Philips XRD unit, equipped with graphite mono- chromatized copper radiation. The weight percentage of silica was calculated through the use of the internal standard and calibration coefficients derived from standards MBS -1878 quartz, NBS -1879 cristobalite, and NIOGH/IITRITY27 tridymite mixed with CaPj. Samples weighing < 0.1 grams were deposited onto a silver membrane filter and analyzed according to a modified NIOSH 7500 method.

Total Sample Identification Quartz Cristobalite Tridymite Crystalline Silica Detection Ghent I.D. RJ Lee Group (Weight %) (Weight %) (Weight”/.) (Weight %) Limit

S12-01 0310771 4.9 4.9 02 S12-02 0340772 5.7 5.7 0.2 S12-03 0340773 1.1 1.1 0.2 S12-04 0340774 1.8 1.8 0.2 Sll-01 0340775 2.3 2.3 0.2 Sll-02 0340776 1.3 1.3 0.2 Sll-03 0340777 1.9 1.9 0.2 Sll-04 0340778 2.5 2.5 0.2 SlO-01 0340779 8.2 8.2 0.2 SI0-02 0340730 1.4 1.4 0.2

*No cristobalite or tridymite detected (< 0.2 wt. % detection limit).

SC/ / A Stephen A. Brown Date Manager, X-ray Diffraction Group

These results are siibmilteil pursuant to RJ Lee Group's mrreut tenus and conditions of sale, including the compiuy's standard warranty and limitalian of liability provisions. No responsMihl or liability is assumedfar the manner in which the results are used or interpreted. Unless notified in writing to return the samples covered try this report, RJ Lee Group will store the samplesfor a period of thirty (30) days bifore discarding A shipping and haiidtingfeeiuill be assessedfor the rehim of any samples.

AIHA Accreditation Certificate Number 460, Monroeville, PA Monroeville, PA * San teandro, CA * Washington, tx;

CITY_21MC100_007082932

NYC-WTC_000188110