DEP memo on 114 Liberty Street clearance data validity, Aug

NYC 9/11 Public Portal Document

enclosures summarizing the analytical results. Included in the letter was reaffirmation of DEP’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 DEP’s April 24,2003 and EPA’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 Ambier r Group Inc. ard analyzed by EMSL Anahlical Inc. for asbestos. An addhional wipe sample and two microvacuum samples were submitted as bla.nks. A summary of the results is presented below.

Location Matrix Sample Minimum Average Maximum I Size Cone. Cone. Cone. (s/cm^) (s/’em^) (s/cm^) All locations s '?■ 4.327.650';/?

Below floor Wipe 1 11.681 11.681

Wall Tracking Wipe 9 8.056 726.108 4.327.650

Below Light Switch \\ ipc 1 8.652 8,652

Blank Wipe 1 2.164 2.164

- 284,^S®~ 4* ...V o.;*a2 2* .XS Below Floor Microvacuum lU 4b.iyz S6>.830 f 1.1 l.V"?

Wall Tracking Microvacuuffl 1 1.5,058 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 71392 71392

Front Office Microvacuum 1 743352 743.552

Blank Mtcrovacuum 2 803 803

VID- asbestos not detectec

2

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