Chain of custody form for DEP environmental samples, 2001

NYC 9/11 Public Portal Document

Post f‘ Cleaning Samples - Three air samples and five wipe samples were collected after the first cleaning. The results for the air samples indicate that MMVF was present; however, the samples were below the primary clearance criterion of 10 SZL. The results of the five wipe samples indicate that MMVF was still present after the first cleaning; however, the concentrations detected were lower than the pre-cleaning samples. There is not a clearance criterion for MMVF in settled dust. Since the air samples were below the primary clearance criterion and the MMVF in settled dust was reduced after the first cleaning, no additional samples were collected for analysis of MMVF.

PAH Before Cleaning Samples - Four pre-cleaning wipe samples were collected. Three of the four samples were below the detection limit; the TEF for these samples was below the primary clearance criterion. PAH compounds were detected in the fourth sample; however, the calculated TEF was below the primary clearance criterion of300 pg/m^.

Post Cleaning Samples - Four wipe samples were collected after the first cleaning. All of the samples were below the detection limit and the TEF for each sample was below the primary clearance criterion of 300 pg/m^. Because all of the samples were below the detection limit and the primary clearance criterion after the first cleaning, no additional samples were collected for analysis of PAH.

Unit 2B - This unit is located on the second floor. It is a 946 sq. ft. loft with two separate bedrooms facing Cedar Street. The unit has hardwood floors and no carpeting. The unit presented minimal dust accumulation, except around baseboard-heating elements. All windows were intact. All personal items except a couch were disposed of prior to cleanup.

Cleaning Method - The unit was cleaned using Test 3 A; an industrial HEPA-filtered vacuum. An AFD was not used. All horizontal surfaces were wet wiped.

Cleaning Results - The unit met the clearance criteria listed in Table 1.0 for each compound after being cleaned once.

Asbestos Before Cleaning Samples - Three micro vacuum and four wipe samples were collected for analysis of asbestos. These samples indicate that asbestos was present in the unit prior to cleaning. Chrysotile was detected in all three micro vacuum samples. Three of the four wipe samples detected chrysotile. One of the three samples also contained Anthophyllite. However, the result for this sample, as well as for the fourth wipe sample, was below the detection limit.

Post J" Cleaning - Test JB - Three air, four micro vacuum, and five wipe samples were collected. Three air samples were analyzed using PCM, TEM AHERA, and PCMe. The PCM results were all below the secondary numeric criterion of 0.01 f/cc. All three TEM AHERA results were below the secondary numeric criterion of 0.022 S/cc. Likewise, all three PCMe results were below the primary clearance criterion of 0.0009 S/cc. The results for four micro vacuum samples indicate that asbestos was present at levels similar to, and in some cases higher than, those observed before cleaning. The results for the five 41

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