DEP memo on vehicle release from Ground Zero, January 24,

NYC 9/11 Public Portal Document 1-24-02:12;30PM;NYC Law Department ;12123618V65 » 18/ 55 JfiN-22-2002 09=51 OSEP UNIT RM. 7345 202 324 9235 P.14X43

Industrial HygieneSun^y Federal Bureau of Investigation, Staten Island, NY

results usually confirm the presence of asbestos fibers. In one case, on October 23, 2001, an air sample analyzed by PCM revealed 0.488 aiid the follow-up TEM analysis 0.106 fZcc. 5. Exposure monitoring of eight (8) workers manually raking out debris in an open area was done on 51 workers and revealed levels ranging from 0.004 to 0.417 free. The average exposure level was 0.08 free. 6. Exposure monitoring of workers while manually raking debris in an enclosed area was done on 12/5/01. Four personal samples werej^fiected and ranged from 0.074 to 0.092. This suggests that the enclosures do not signifieffiSy increase exposure levels. 7. Exposure monitoring of workers while inspecting debris at a screener was done on 11/9/01 and 11/14/01. On both days the screener was not enclosed, but was in the open 1 air. The results ranged from 0.051 to 0.251 f/cc. The average level was 0.143 free. 8. Personal sampling was conducted on a FBI bomb technician while working throughout the day searching cars removed from the WTC site. The exposure level was 0.303 free. Additional analysis of the sample by TEM revealed an exposure level of 0.488 free.

These findings indicate that workers should continue to wear the half face respiratory protection currently issued while working in the debris field. Tyvek suits and gloves should also be used. The results indicate that exposures to asbestos can exceed the PEL as much as 30 % of the time. When the PEL is exceeded it is usually by a very small margin and never approaches the maximum allowable limit for a half face respirator.

Metals in Air Samples Both personal and area sampling was conducted for metals in air. The results of metal scans were summarized in the prior report. Additional sampling for metal scans has not been conducted since the earlier report Additional sampling was conducted for lead exposure. For the total metal scans, four personal samples were collected on workers in the debris field and one area sample was collected. Only five metals were detected in the samples. These include aluminum, calcium, magnesium, barium, and manganese. The levels of each of the metals scanned were well below the OSHA PEL. The levels of metals measured are summarized below:

Metal OSHA PEL Level Detected Silver 0.01 mg/M3 <0.006 mg/Ma Aluminum 15mg/M3 0.008 to 0.01 mg/M3 Arsenic 0.01 mg/M3 <0.2 mg/M3 Antimony 0.5 mg/M3 <0.001 mg/M3 Barium 0.5 mg/M3 <0.002 mg/M3 Beryllium 0.002 mg/M3 <0.0002 mg/m3 Cadmium 0.005 mg/M3 <0.0002 mg/M3 Cobalt O.l mg/M3 <0.002 ing/M3 Chromium 1 mg/M3 <0.002 mg/M3 Copper 1 mg/M3 <0.004 mg/M3 Iron 10mg/M3 <0.021 mB/M3 Lead 0.05 mg/M3 <0.0005 mg/m3 Magnesium 15 mg/M3 0.012 mg/M3 Manganese 5 mg/M3 0.0005 mg/M3

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