NYC-WTC_000195194

NYC 9/11 Public Portal Document

Sample Handling and Shipment Samples transported to EMSL were typically picked up by an EMSL courier the day after sample collection. A small percentage of the EMSL samples, and all of the samples transported to Paradigm Analytical, were shipped via Federal Express. Several samples were damaged during shipment and are so documented in Attachment J, Reporting ofAnalytical Results.

At the conclusion of each sampling event, chain of custody (COC) records were generated electronically using Scribe? v2.2 software. A copy of the COC records were printed, signed, and shipped with the samples to the lab. The only COC records not generated in this fashion were those for the April 30, 2002 bulk sampling event and the personal monitoring samples collected by WRS.

3.7 Analytical Data

yalidation The validation of all organic and inorganic analytical data was performed in accordance with the QAPP. Validation of inorganic data was performed by Weston. Validation of organic data was performed by EPA Region 2 personnel.

Reporting All analytical results were tabulated subsequent to validation and are provided in Attachment J, Reporting ofAnalytical Results.

3.8 Difficulties Encountered and Resolutions

Sample Overloading Initially, many of the asbestos analyses were reported by the laboratory as overloaded. After consulting with the laboratory, it was determined that a reported value of overloaded did not mean that the sample cassette was overloaded with asbestos. Rather, the filter contained particulate matter that could obstruct the field of view of the laboratory analyst.

The only resolution to the problem of sample overloading was the repeated cleaning of the units. It was only after the presence of settled dust was minimized through cleaning that the aggressive and modified-aggressive sampling techniques were able to be used to collect air samples that did not have overloaded filters.

Data Reporting Given that nearly 3,000 samples were collected and submitted for analysis during the course of the study, EPA’s inability to receive laboratory data in a timely manner was a major and ongoing problem. The greatest impact was felt in the scheduling of time and resources for the re-cleaning of the units. The delay in receiving data resulted in the inability to determine if re-cleaning was necessary, which in turn complicated the scheduling of day-to-day work and resource requirements In many cases, the last minute redirection of the cleaning and sampling contractor’s resources was required in an effort to maintain productivity. Furthermore, many of the data packages were incomplete upon receipt, delaying EPA’s ability to validate the data in a timely manner, and resulting in delays in issuing final building clearance and the completion of this report.

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