Air sampling report for metals at School for Leadership, March

NYC 9/11 Public Portal Document

Mr. Bernard P. Orlan March 29, 2002 Air Sampling for Metals Page 2 H.S. for Leadership & Pub. Service (894M) ATC Project No. 15-19125-0290

The Cr concentrations in these samples are shown in Table 1.

TABLE 1 CHROMIUM (Cr) IN AIR CONCENTRATIONS March 1, 2002 ■BB!llf!!|!i!jl(!W IBSSSIISilJlB Cr IN LOCATION CrINAIR SAMPLE NO. (ug/m’) 1“ Floor Lobby Ml 0.563 0.469 0.143 5“’ Floor- Hallway by elevator / M2 0.638 0.532 0.206 10* Floor Hallway by elevator / M3 0.415 0.346 0.02

Roof/M4 0.700 0.583 0.257

Blank / M5 0.391

The Environmental Protection Agency (EPA) has set a screening level for hexavalent chromium (the more toxic form) in air of 0.6 ug/m\ this assumes a continuous exposure for one year. The samples here v/ere analyzed for total chromium (trivalent and hexavalent). All of the Cr concentrations detected here are below the EPA screening level.

The other metal present over the limit of detection was Pb. The Pb concentrations are shown in Table 2. TABLE 2 LEAD(Pb) IN AIR CONCENTRATIONS March 1, 2002 11! WCOI^CTED LOCATION PblNSA.MPLE i PblNAIR SAMPLE NO. (ug/sample) (ug/m*) (ug/m’) i Fnhbr Lobby Ml 0.327 0.272 BDL* 5* Floor Hallway by elevator / M2 BDL BDL 10* Floor Hallway by elevator / M3 0.311 0.259 BDL

Roof7M4 0.344 0.287 0.005

Blank/M5 0.338 * Below Detection Limit

CONFIDENTIAL, CITY_21MC100_003431660 SUBJECT TO PROTECTIVE ORDER NO. 2, SEPT. 2008

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