NYC-WTC_000232127

NYC 9/11 Public Portal Document

Part II - Environmental Community Monitoring Plan 133-135 Greenwich & 21-23 Thames Streets Airtek Project 05-0701 - Rev 2 September 16, 2005

Precision # 5 Fg/m for cone. 80 ng/m3 40 CFR, Pt 50, Both PMIO values must be Single analyzer 1/6 days App M, S 4.1 > 20 pg/m . IVo for cone. >80 pg/m Reporting 1/ 3 months 95% CI < ± 15% 40 CFR, Pt 58, organization App A, S 5.3 EPA-600/4-83-023 Accuracy Transfer standards different Single analyzer Quai'terly None 40 CFR, Pt 58, then those used in Annual accuracy (all sites yearly) 95% CI # + 20% App A calibration. Recalibrate EPA-600/4-83-023 quarterly (all sites before Vol II, App 15, S 6 any additional sampling. Invalidate data to last acceptable flow yearly) check if difference > 10%. QC Checks Field calibration flow I/month Percentage difference # ±7 40 CFR, Pt .50, check from sampler's indicated App M, S 8.2 Trouble shoot and flow rate or # ± 10 % from Vol II, MS 2.10.3 recalibrate sampler. "Standard" filter at beginning of design condition flow rate weighing weighing day + 20 g of original weight Vol II, S 2.10.4 Trouble shoot and reweigh. Reweighing filters 5 exposed and 5 unexposed/day ± 20 g of original weight Trouble shoot and reweigh. 1/montli ± 2 g at 10 mg Vol II, S 2.10.4 Trouble shoot and reweigh.

Balance zero and every fifth filter- ± 4 g at zero Calibration check ± 2 g at 10 mg Vol II, S 2.10.4

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CITY_DEP_WORBY_CANNATA_SUBP_000087283

NYC-WTC_000232164