NYC-WTC_000195194

NYC 9/11 Public Portal Document

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

Post P‘ Cleaning Samples - Two air samples were collected after the first cleaning. All of the samples were below the detection limit.

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

Post P‘ Cleaning Samples - Two air samples were collected after the first cleaning. All of the samples were below the detection limit.

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

Post P‘ Cleaning Samples - Two air samples were collected after the first cleaning. All of the samples were below the detection limit.

MMVF Before Cleaning Samples - Three pre-cleaning wipe samples were collected. The three wipe samples contained MMVF detected at concentrations from 57.23 S/cm^ to 1030.17 S/cm^. This indicates that MMVF was present prior to cleaning.

Post P‘ Cleaning Samples - Three air samples and five wipe samples were collected after the first cleaning. All of the air sample results indicate that MMVF was present, but at concentrations below the primary clearance criterion of 10 S/L. The wipe sample results were detected in concentrations ranging from 57.23 S/cm" to 343.39 S/cm^ which were similar to or lower than the pre-cleaning samples.

PAH Before Cleaning Samples - Three pre-cleaning wipe samples were collected. Two of the three samples were below the detection limit; the TEF for each sample was below the primary clearance criterion. PAH compound was detected in the third sample; however the calculated TEF was below the primary clearance criterion of 300 pg/m^.

Post f* Cleaning Samples - Two post-cleaning air samples and four post-cleaning wipe samples were collected. Both air samples had seven PAH compounds detected; however, the calculated TEFs for these samples were below the primary clearance criterion of 0.2 |xg/m^. All wipe samples were below the detection limit and the TEF for each sample was below the primary clearance criterion of 300 pg/m^.

Unit 4D - This unit is on the fourth floor. It is a 968 sq. ft. open loft facing the WTC site. The unit had windows blown in and presented a significant accumulation of dust. The dwelling has hardwood floors with no carpet. All personal possessions to be retained by the tenant were vacuumed and bagged.

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