NYC-WTC_000195194

NYC 9/11 Public Portal Document

Post P* Cleaning Samples - Two air samples were collected. The results for both samples were below the primary clearance criterion of 10 S/L. w

Mattress Store - This is a 968 sq. ft. open space facing the World Trade Center site. All front windows were blown in. Significant amounts of dust were present on all horizontal surfaces. Floor areas were covered with wall-to-wall carpeting. Approximately 25 display mattresses and «r box springs were present. Ceiling tiles, mattresses, office equipment and flexible ventilation ducts were removed and disposed of prior to cleaning. The space above the suspended ceiling exhibited the same characteristics as in the Chiropractor’s Office. w Cleaning Method - This unit was the subject of separate tests to evaluate five different cleaning techniques as described below;

Test 4A: Industrial HEPA-filtered vacuums and AFD Test 4B: Wet wipe all walls Test 4C: Hot water carpet shampoo Test 4D: A/C duct cleaning Test 4E; Cleaning of vinyl floor tile and wet wipe of window ledge using water only

Cleaning Results - This unit met the clearance criteria listed in Table 1.0 for each compound after the Test 4E cleaning event except for one lead wipe which was collected from a window ledge.

Supplemental Sampling Activities - Prior to initiating pre-cleaning sampling activities as described below, EPA collected a bulk composite sample from the Mattress Store. The analytical data obtained from the bulk composite was utilized in identifying COPC concentrations present in settled dust, determining the applicability of regulatory standards, and identifying potential health and safety concerns. The Mattress Store was selected, based upon visual observation, as being representative of a “worst case scenario” in the study building.

Asbestos Before Cleaning Samples - Four air, seven micro vacuum, and three wipe samples were collected for asbestos. The air samples were analyzed for PCM and PCMe. The PCM results indicate that two of the samples were above and two of the samples were below the secondary numeric criterion of 0.01 free. The PCMe results indicate that two of the samples could not be analyzed due to overloading of particulate material. The remaining two samples were below the detection limit and below the primary clearance criterion of 0.0009 S/cc. All seven of the micro vacuum samples and all three of the wipe samples detected chrysotile. «iar Post P‘ Cleaning Samples (Test 4A) - Three air samples, seven micro vacuum samples W and four wipe samples were collected for asbestos. The air samples were analyzed for w PCM, TEM AHERA, and PCMe. The PCM results indicate that all three samples were below the secondary numeric criterion of 0.01 free. The TEM AHERA results indicate w that two of the samples could not be analyzed due to overloading of particulate material. The remaining sample was below the secondary numeric criterion of 0.0022 S/cc. The PCMe results indicate that two of the samples could not be analyzed due to overloading of

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NYC-WTC_000195293