FEMA letter wipe sampling methodology corrections, August 2003

NYC 9/11 Public Portal Document

enclosures summarizing the analytical results. Included in the letter was reaffirmation of DBF’s Asbestos Control Program’s staff observations whereby pre-existing building materials were identified as being suspect asbestos-containing material (ACM). Those materials included thermal system insulation, surfacing material and vinyl asbestos tiles. Copies of DBF’s April 24, 2003 and BPA’s April 18, 2003 letters are attached for your perusal.

The following provides the results of our review of the above-described data submitted to you by the residents of 114 Liberty Street:

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 Sampie Minimum Average Maximum Size Cone. Cone. Cone. (s/cm^) (s/cm^) (s/cm^) All locatioas W.pe n 8,056 >5,937 4,327,<0O; ■1 __________ Below floor Wipe 1 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

All IxKation I 16 284.488 1,115,570 ___________ is _________ Below Roor Microvacuum 10 40,192 369,830 1,115,570

Wall Tracking Microvacuum I 15,058 15,058

I-beam Microvacuum 2 ' 7,636 7,636 8,038 (ND)

Column Microvacuum 1 8,038 (ND) 8,038 (ND)

Pipe Shaft Microvacuum 1 71,592 71,592

Front Office Microvacuum 1 743,552 743,552

Blank Microvacuum 2 803 803

ND= asbestos not detected

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