Forwarding WTC air monitoring scope for final review, Aug 2002

NYC 9/11 Public Portal Document

Pt. 763, Subpt. E. App. A 40 CFR Ch. I (7-1-00 Edition) 6. Minimum sample number per site. A that electrical equipment does not become minimum of 13 samples are to be collected wet while operational. for each testing consisting of the following; vl. Low volume pumps may be carefully a. A minimum of five samples per abate­ wrapped in 6-mll polyethylene to Insulate ment area. the pump from the air. High volume pumps b. A minimum of five samples per ambient cannot be sealed In this maimer since the area positioned at locations representative heat of the motor may melt the plastic. The of the air entering the abatement site. pump exhausts should be kept free. c. Two field blanks are to be taken by re­ Vil. If recleaning Is necessary, removal of moving the cap for not more than 30 sec and this equipment from the work area must be replacing it at the time of sampling before handled with care. It Is not possible to com­ sampling is initiated at the following places: pletely decontaminate the pump motor and 1. Near the entrance to each ambient area. parts since these areas cannot be wetted. To 11. At one of the ambient sites. minimize any problems in this area, all (Note; Do not leave the blank open during equipment such as fans and pumps should be the sampling period.) carefully wet wiped prior to removal from d. A sealed blank is to be carried with each the abatement area. Wrapping and sealing sample set. This representative cassette is low volume pumps In 6-mll polyethylene will not to be opened in the field. provide easier decontamination of this 7. Abatement area sampling. equipment. Use of clean water and disposable a. Conduct final clearance sampling only wipes should be available for this purpose. after the primary containment barriers have e. Pump flow rate equal to or greater than been removed; the abatement area has been I L/mln or less than 10 L/min may be used for thoroughly dried: and, it has passed visual 25 mm cassettes. The larger cassette diame­ Inspection tests by qualified personnel, (See ters may have comparably Increased flow. Reference 1 of Unit III,L.) f. Sample a volume of air sufficient to en­ b. Containment barriers over windows, sure the minimum quantitation limits. (See doors, and air passageways must remain In Table I of Unit III.B.S.J.) place until the TEM clearance sampling and 8. Ambient sampling. analysis is completed and results meet clear­ a. Position ambient samplers at locations ance test criteria. The final plastic barrier representative of the air entering the abate­ remains In place for the sampling period. ment site. If makeup air entering the abate­ c. Select sampling sites in the abatement ment site is drawn from another area of the area on a random basis to provide unbiased building which is outside of the abatement and representative samples. area, place the pumps in the building, pumps d. After the area has passed a thorough vis­ should be placed out of doors located near ual inspection, use aggressive sampling con­ the building and away from any obstructions ditions to dislodge any remaining dust. that may Influence wind patterns. If con­ 1. Equipment used in aggressive sampling struction is in progress immediately outside such as a leaf blower and/or fan should be the enclosure, it may be necessary to select properly cleaned and decontaminated before another ambient site. Samples should be rep­ use. resentative of any air entering the work site, 11. Air filtration units shall remain on dur­ b. Locate the ambient samplers at least 3 ing the air monitoring period. ft apart and protect them from adverse ill. Prior to air monitoring, floors, celling weather conditions. and walls shall be swept with the exhaust of c. Sample same volume of air as samples a minimum one (1) horsepower leaf blower. taken inside the abatement site. Iv. Statlonaiy fans are placed In locations C. Sample Shipment which will not Interfere with air monitoring equipment. Fan air is directed toward the 1. Ship bulk samples In a separate con­ ceiling. One fan shall be used for each 10,000 tainer from air samples. Bulk samples and ft’ of worksite. air samples delivered to the analytical lab­ V. Monitoring of an abatement work area oratory In the same container shall be re­ with high-volume pumps and the use of cir­ jected. culating fans will require electrical power. 2. Select a rigid shipping container and Electrical outlets in the abatement area pack the cassettes upright In a noncontami­ may be used if available. If no such outlets nating nonflbrous medium such as a bubble are available, the equipment must be sup­ pack. The use of resealable polyethylene plied with electricity by the use of extension bags may help to prevent Jostling of Indi­ cords and strip plug units. All electrical vidual ceissettes. power supply equipment of this type must be 3. Avoid using expanded polystyrene be­ approved Underwriter Laboratory equipment cause of its static charge potential. Also that has not been modified. All wiring must avoid using particle-based packaging mate­ be grounded. Ground fault interrupters rials because of possible contamination. should be used. Extreme care must be taken 4. Include a shipping bill and a detailed to clean up any residual water and ensure listing of samples shipped, their descriptions

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NYC-WTC_000139301