JLC Environmental purchase order form, March 19, 2003

NYC 9/11 Public Portal Document

Penny Theodorellys,

From: [email protected] Sent: Tuesday, March 18, 2003 11:59 AM To: Theodorellys, Penny Cc: Radhakrishnan, Krish; Gilsenan, Michael; [email protected]; [email protected]; [email protected] Subject: Re: FW: PAH results US DEP - WTC

R03030157 Cover R03030157 Report.pdf R03030158 Cover R03030158 Report.pdi Letter.pdf Letter.pdf

Penny,

I am back from vacation and had a chance to take a look at the data (i.e., asbestos, lead and PAH) from 114 Liberty that you sent over last week. Overall the data that you sent looks good but there are several problems with the reporting limits (i.e., analytical sensitivity). 1) The PAH data indicates that the reporting limit used is 5 ug. This does not allow us to compare the results to the health-based benchmark because the reporting limit is higher than the benchmark. The reporting limit that was supposed to be used was 1 ug (as stated on page 3, item #5 in the scope of work). I hope future PAH analyses can use the appropriate reporting limit as it will result in data that can be compared to the health-based benchmark. 2) The asbestos data indicates that the reporting limit used is 0.0009 s/cc. This is acceptable for comparing to the health-based benchmark but the reporting limit that was supposed to be used was 0.0004 s/cc (as stated on page 4, Asbestos Collection and Analysis, item #2). Using the lower reporting limit will add confidence that the concentrations are below the health-based benchmark rather than being "at" the health-based benchmark and it is also what is being used in our residential cleaning project and it is what was used for 125 Cedar Street. 3) The lead data indicates that the reporting limit used is 20 ug/ft2. Again, this is acceptable for comparing to the health-based benchmark of 25 ug/ft2, but for our projects we used a reporting limit of 2.32 ug/ft2 and a reporting limit of 9 ug/ft2 was used for 125 Cedar Street. A summary of the data I have received to data is presented below: Asbestos - TEM 40 samples at or below the health-based benchmark of 0.0009 (28 were below the reporting limit of 0.0009), 1 above health-based benchmark @ 0.0018 s/cc Asbestos/Fibrous Glass - PCM 3 samples were below the health-based benchmark of 0.01 f/cc and 2 samples were overloaded and could not be analyzed.

NYC-WTC 000101256