Ambient air sampling report, 40 Rector Street, Sep-Oct 2001

NYC 9/11 Public Portal Document

iJ 40 Rector Holdings, LLC ATC Project No.: 19855-0001 C/0 Tannenbaum Helpern Syracuse & Hirschtritt LLP October 25,2001 Ambient Air Sampling - 40 Rector Street Page 2 Of 7

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Based upon analytical sample results following both cleaning episodes recording levels within the AHERA clearance requirement, it is ATC’s opinion that the ambient air samples collected and lAQ measurements collected throughout the building are representative of the ambient conditions at the time of testing and that the areas tested meet an acceptable criterion for re-occupancy.

Ambient Air Sampling - Initial Cleaning Between September 20 and 28, 2001, ATC collected a minimum of five ambient air samples per floor representative of ambient air conditions following the initial cleaning of 40 Rector Street. All field generated air monitoring data and chain of custody forms and laboratory generated analytical data is included in Attachment 2 at the end of this report. A summary of the data is provided in Table 1. Table 1 Summary of Ambient Air Sample Results Initial Cleaning Floor ______ Analytical Result_____ Floor Analytical Result 1 No structures detected______ 10 All samples <70 s/mm^ lJ 2 All samples <70 s/mm^______ 11 All samples <70 s/mm^ 3 All samples <70 s/mm^______ 12 All samples <70 s/mm^ 4 All samples <70 s/mm^ 14 All samples <70 s/mm^ uJ 5 Sample set average 23 s/mm^ 15 ' All samples <70 s/mm^ 6 All samples <70 s/mm^______ 16 No structures detected t_.J 7 All samples <70 s/mm^______ 17 All samples <70 s/mm^ 8 All samples <70 s/mm^______ 18 All samples <70 s/mm^ 9 All samples <70 s/mm^ 19 All samples <70 s/mm^

n Based upon the analytical results recording levels within the AHERA clearance requirement, it is ATC’s opinion that the ambient air samples collected throughout the building are representative of the ambient conditions at the time of testing and that the n areas tested meet an acceptable criterion for re-occupancy.

n u Ambient Air Sampling - Subsequent Cleaning Between October 22 and 23, 2001, ATC collected a minimum of five ambient air samples per floor representative of ambient air conditions following the subsequent cleaning of 40 Rector Street. All field generated air monitoring data and chain of

■"1 ATC Associates Inc. © 2001 I J

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