NYC-WTC_000232541

NYC 9/11 Public Portal Document

I Bulk# 5 (JL) from debris NA asbestos ND NA pile, Plaza silica 1.9% area lead 0.01 % iron 1.1 % aluminum 0.94% copper 0.03 % magnesium 0.81 % sulfur 2.0% calcium 11% BuIk#5(NL) coating on NA asbestos-chrysotile 15% NA 4'X 2’steel silica 1.0% beam on lead <=0.01% rubble pile iron 1.5 % aluminum 2.6% copper ND magnesium 5.7% sulfur 3.4% calcium 21%

TWA = Time Weighted Average PEL = Permissible Exposure Limit PESH = NYS Public Employee Safety and Health Bureau free = Fibers per Cubic Centimeter ppm = parts per million mg/m’ = milligrams per cubic meter ug/m^ = microgram per cubic meter STEL = Short Term Exposure Limit Peak = Highest Level Seen During Test ND = not detected NA = not Applicable % = Percent = Less Than = Less Than or Equal To ♦♦ = Metals scan also included; Aluminum, Chromium, Copper, Don, Magnesium, Mangenese, Molybdenum, and Nickel. Analytical Method for total dust is based on NIOSH 0600 Analytical Method for sUica is based on OSHAID142 and NIOSH 7500 Analytical Method for metals is based on OSHA ID 125G ‘ = Sample result based on analytical method NIOSH 7400. This method utilizes Phase Contrast Microscopy (PCM) which counts ALL FIBERS longer than 5 microns in length and have a length to width ratio equal to or greater than 3:1. 2 = Sample result based on analytical method NIOSH 7402. This method utilizes Transmission Electron Microscopy (TEM) to identify and quantify asbestos fibers present ’ = Cassette sample was overloaded for the purpose of TEM analysis * = The Action Level for lead is 0.030 mg/m^ ’ = silica containing materials are generally considered as silica dust when the % silica is > 1%. * = The Ceiling Limit for carbon monoxide is to be measured over a 5 minute sample. = Results may include soluble non-sulfuric acid sulfate compounds

CONFIDENTIAL, CITY_21MC100_013418579 SUBJECT TO PROTECTIVE ORDER NO. 2, SEPT. 2008

NYC-WTC_000232543