NYC 9/11 Public Portal Document
Even if Region 1 did not want to use this published data on typical dust levels, it had it own data,
developed during the testing of the Brookfield schools, that showed that clean surfaces and clean
schools had much, much lower background dust levels.
Re-calculation of Region 1 dust benchmark with more appropriate values
Table 4 gives re-calculated values for dust benchmarks using more appropriate, accurate, and
defensible values for ambient background air and K-factors. A range of different calculations is
given, showing the effect of substituting several different values. In all cases, the result is a
much lower dust benchmark than the one contrived by Region 1.
Brookfield School System and community rejection of EPA Region 1 benchmark
of 45,000 s/cm^ for dust
The Brookfield School System in Connecticut and the community has rejected EPA Region I's
benchmark for dust of45,000 s/cm’ as not being well founded or protective. It has been
tentatively decided that a level of 5000 s/cm’ is the cleanup goal.” Because data clearly
demonstrate that a cleaned surface, even in an asbestos-contaminated building, will only have 86
to 320 s/cm’ asbestos (see Table 2) there is no reason why the cleanup standard should not be
much lower.
As a brief history of the problem, recently teachers at the Huckleberry Hill elementary school in
Brookfield, Connecticut were concerned with an asbestos abatement in the year 2000 where the
Region 1 benchmark of 45,000 s/cm’ was the standard. The teachers hired an independent
industrial hygienist. Side-by-side testing was performed with the school system’s testing
consultant. High levels of asbestos were found by the ASTM 5755 microvacuum method in two
carpets (over 462,240 and 329,560 s/cm’) as well as on top of a fire alarm box (over 3 million
s/cm’) and on bare floors in another corridor (around 150,000 s/cm’).’^
The students were to be transferred to a middle school to finish the year, but this school was
tested and also found to have high asbestos dust levels, and failed the AHERA air test. At
another school, asbestos was found in surface dusts at concentrations as high as 14 million s/cm^.
The whole school system was then shut down for the rest of the school year for further testing
and inspection.’’
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