NYC-WTC_000195194

NYC 9/11 Public Portal Document

w Unit 5A - This unit is on the fifth floor. It is a 1,404 sq. ft. loft facing Cedar Street with one bedroom. The unit has hardwood floors and no carpet. One window had been blown in. The dwelling presented minimal accumulation of dust, except for baseboard-heating units. Numerous w items were cleaned, then bagged. «r Cleaning Method - This unit was cleaned using Test 3B: an Industrial HEPA-filtered vacuum. An AFD was used during cleaning. In addition, all horizontal surfaces were wet wiped.

W Cleaning Results - This unit met the clearance criteria listed in Table 1,0 for each compound after being cleaned twice.

Asbestos w Before Cleaning Samples - Seven 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 six of the seven micro vacuum samples and all four of the wipe samples; however, chrysotile was present below the detection limit in two of the four wipe samples.

Post Cleaning - Three air samples, seven micro vacuum samples, and five wipe samples were collected. The three air samples were analyzed using PCM and PCMe. The PCM results were all below the secondary numeric criterion of 0.01 f/cc. All three PCMe analyses were at or below the primary criterion of 0.0009 S/cc.

The results for the seven micro vacuum samples indicate that asbestos results varied and were present at levels higher and lower than before cleaning.

The results for the five wipe samples showed that asbestos was present in one sample; however, all samples were below the detection limit. The results indicate that the cleaning techniques used were effective in reducing the asbestos concentrations observed prior to cleaning.

Dioxin Before Cleaning Samples - Three wipe samples were collected and analyzed for dioxin. The results indicate that dioxin was present; however, the TEQ concentration for each sample was below the primary clearance criterion of 4 ng/m^.

Post P‘ Cleaning Samples - Four wipe samples were collected and analyzed for dioxin. The results indicate that the TEQ concentration for each sample was below the primary clearance criterion of 4 ng/m^.

w Gypsum Before Cleaning Samples - Pre-cleaning air samples were not collected.

Post P' Cleaning Samples - Two air samples were collected after the first cleaning. Gypsum was not detected in any sample.

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NYC-WTC_000195267