Dust survey results, 75 Park Place, Oct 2001

NYC 9/11 Public Portal Document

ambient group inc.

SUBJECT

As part of the on going assessment of materials at 75 Park Place Ambient Group, Inc. conducted a dust survey on October 20, 2001 to determine the constituents in the materials at 75 Park Place. The survey included sampling for bulk and settled dust characterization. As a result, one (1) of the bulk samples collected from the 9"' floor southeast corner, was determined to be positive for the presence of asbestos (2% of Chrysotile asbestos). All dust characterization samples tested negative for the presence of asbestos.

In response, Ambient Group, Inc.

returned to 75 Park Place, on October 25,, 2001, to perform a more detailed survey of the southeast corner on the 1 9' floor. This survey identified a very limited area (<I square foot) of material as asbestos containing. This material was located within one perimeter heating unit.

In response to this, on October 28, 2001 air monitoring was performed during a dust control project in this area on the 9"' floor. AES cleaned (using HEPA VAC and wet wipe techniques) the below and above ceiling surfaces in the southeast corner. Ambient Group, Inc. was responsible for air sample collection, analysis, and data reporting during this work. All material identified as asbestos was removed and the area successfully passed reoccupancy testing.

In its role as air monitor during dust control procedures, Ambient Group Inc. collected air samples during the project to determine if the Contractor was containing airborne fibers within the work site.

Ambient Group, Inc. collected and analyzed a total of four (4) airborne fiber samples over the course of this project. Of this total, two (2) were contamination samples and two (2) samples were re-occupancy samples.

The results of the sample analyses indicated airborne fiber levels below 0.01 fi bers/cm'. The work site where dust control removal took place was released for re-occupancy only after meeting New York State Department of Labor airborne fiber re-occupancy criteria, and was free of visible debris.

ACM sample locations from October 20, 2001 can be found (marked on drawings) in Appendix A. The sample results from October 20, 2001 can be found in Appendix B. The sample results from October 25, 2001 can be found in Appendix C. The sample results from October 28, 2001 can be found in Appendix D. An explanation of the air sample codes used in the laboratory reports can be found in Table 1.

IIAMBIENT SVR3L4MBJEN7120011reporfl4irl211358. 75 Park Place.doc I

NYC-WTC 000096047