NYC 9/11 Public Portal Document
Alpha-Quartz
Before Cleaning Samples - Pre-cleaning air samples were not collected.
Post P‘ Cleaning Samples - Two air samples were collected after the first cleaning. All
samples were below the detection limit.
Calcite
Before Cleaning Samples - Pre-cleaning air samples were not collected
«r
w Post P‘ Cleaning Samples - Two air samples were collected after the first cleaning. All of
the samples were below the detection limit.
«r
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
were below the detection limit.
MMVF
Before Cleaning Samples - Two pre-cleaning air samples and three pre-cleaning wipe
samples were collected. The two air samples had MMVF detected, but were below the
primary clearance criterion. The three wipe samples had MMVF detected in
concentrations from 57.23 S/cm’ to 801.24 S/cm7
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 at levels
« below the primary clearance criterion of 10 S/L. All of the wipe sample results were
below the detection limit of 22.89 S/cm^. This indicates that the cleaning method was
able to reduce the pre-cleaning concentration of MMVF.
PAH
Before Cleaning Samples - Three pre-cleaning wipe samples were collected. All three
were below the detection limit. The TEF for each sample was below the primary
clearance criterion.
w Post P‘ Cleaning Samples - Four post-cleaning wipe samples were collected. All four
were below the detection limit. The TEF for each sample was below the primary
clearance criterion of 300 pg/m^.
47
CITY_21MC100_011105277
NYC-WTC_000195243
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