Minerals and fibers analysis report, Bldg 26 Nov 2001

NYC 9/11 Public Portal Document

Please refer to the previous part of this report (executive summary) for the limitations of this data, the possible symptoms of exposure, and recommendations on how to reduce your potential for exposure.

Table la Crystalline Minerals in Air for Building 26 and the upper Manhattan Comparison Area (milligrams per cubic meter of air)

Building 26 Comparison Area Minerals in Air Inhalable Thoracic - Inhalable Thoracic - (PM100) Respirable (PM100) Respirable (PM10-PM4) (PM10-PM2.5) Quartz Detected ND ND ND Cristobalite ND ND ND ND Tridymite NA NA NA NA Calcite ND ND ND ND Portlandite ND ND ND ND Gypsum ND ND Detected Detected Mica ND ND ND ND Halite ND ND ND ND

NA = not analyzed ND = not detected

Table lb Approximate Levels Crystalline Minerals in Settled Dust for Building 26 and the upper Manhattan Comparison Area (percent of sample containing the mineral)

Building 26 Comparison Area* Minerals in Common Outdoor Residence Residence Common Outdoor Residences Settled Dust Area #1 #2 Area Quartz 0.7 NS ND ND 1.3 NS 2.2 Cristobalite ND NS ND ND ND NS ND Tridymite ND NS ND ND ND NS ND Calcite 1.6 NS ND ND CI.4 NS 0.9 Portlandite 0.6 NS ND ND 0.1 NS 0.1 Gypsum 2.3 NS ND 0.1 3.1 NS 4.2 Mica 0.1 NS ND ND ND NS 0.1 Halite ND NS ND ND ND NS 0.4

*Results are maximum values found in the comparison area NS = not sampled ND = not detected

CONFIDENTIAL, CITY_21MC100_003434275 SUBJECT TO PROTECTIVE ORDER NO. 2, SEPT. 2008

NYC-WTC_000176158