NYC-WTC_000195194

NYC 9/11 Public Portal Document

Lead Before Cleaning Samples - Four pre-cleaning wipe samples were collected. Three of the four samples were above the detection limit. The fourth sample was below the detection limit. Two were above the primary clearance criterion of 25 pg/ft^. Two of the samples were qualified as rejected due to field blank contamination.

Post P‘ Cleaning Samples - Two air samples and four wipe samples were collected after the first cleaning. All of the air and wipe samples were below the detection limit and met the primary air and wipe clearance criteria for lead after the first cleaning.

MMVF Before Cleaning Samples - No pre-cleaning samples were collected for MMVF

Post P‘ Cleaning Samples - Three air samples were collected after the first cleaning. MMVF was detected in two of three samples, but at levels below the primary clearance criterion of 10 S/L.

PAH Before Cleaning Samples - Four wipe samples were collected. All of the samples were below the detection limit. The TEF for each sample was below the primary clearance criterion. One PAH compound was detected in the fourth sample; however, the TEF was below the primary clearance criterion of 300 pg/m^.

Post P‘ Cleaning Samples - Four wipe samples were collected. All four samples were below the detection limit. The TEF for each sample was below the primary clearance criterion of300 pg/m^.

Cedar Street Staircase - This area consisted of wood steps/landings, sheet rock walls and ceiling. Flooring was covered with vinyl tiles; walls and ceilings were covered with gloss paint.

Cleaning Method - This area was cleaned using Test 4A and Test 4B. Test 4A utilized a commercial HEPA-filtered vacuum and an AFD. Test 4B consisted of soap and water wet wipe of all horizontal and vertical surfaces.

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

Asbestos Before Cleaning Samples - There were no samples collected before cleaning.

Post P‘ Cleaning Samples - Two air samples were collected. The air samples were analyzed using PCM, TEM AHERA, and PCMe. The PCM results were below the secondary numeric criterion of 0.01 F/cc The TEM AHERA results indicate that chrysotile was present, but both samples were below the secondary numeric criterion of 0.022 S/cc. The PCMe results indicate that one sample was below the detection limit and the other had chrysotile present, but at a concentration below the primary clearance

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