NYC-WTC_000233245

NYC 9/11 Public Portal Document

RJ LQQGroup, Inc. Exceedance Report

Date of Exceedance: February 26, 2005 Analyte: Airborne Asbestos Location: Carlisle Street AFD Exhaust Concentration: 217.9 s/mm^ Trigger Level: 70 s/mm^

Summary of Event:

On Saturday, February 26, 2005 sampling for airborne asbestos fibers was conducted at the Carlisle Street, AFD Exhaust (BL6 location). The sampling was initiated at 7:45AM on February 26, 2005 and concluded at 1:22PM that same day (total collection time: 337; sample volume: 1685 liters). The sample was received by the laboratory on Sunday, February 27 and analyzed during the early morning of February 28, 2005 using the AHERA TEM method. The results from the analysis of the sample reported an asbestos fiber concentration of 217.9 s/mm^. The results from the two other samples obtained on Carlisle Street during the same time period were non-detect (< 5.6 s/mm^) for asbestos fibers.

Corrective Action:

Work in the basement area was stopped following notification of the exceedance sample and an investigation was performed to evaluate the possible cause(s) of the elevated level reported. Observations by field personnel suggested that the source of the asbestos fibers was related to a damaged HEPA filtered Air Filtration Device (AFD) that was located in the basement.

It appears that when the workers were demolishing piping and/or ductwork above the AFD to access areas where trapped WTC dust may exist, something fell and damaged the AFD to a point where the seal (gasket) surrounding the HEPA filter in the AFD was breeched and unfiltered air passed around the HEPA filter (see attached photographs of damage AFD).

The AFD in question has been taken out of service and replaced.

The DEP & EPA were notified of this exceedance and our findings on the morning of February 28, 2005.

Attachments:

Report summary -AHERA TEM Air Results for February 26, 2005 Figures - Air sampling maps of asbestos TEM locations for February 26, 2005 Photos obtained of the damaged AFD Unit

Submitted By: Mike Campbell Date: March 1, 2005 Revision J

CITY_21MC100_0 02651433

NYC-WTC_000233245