Question_Answer_Set_Two.pdf

Question and Answer Set Two

F17PS00726

1. Regarding the Attachment D - Organic Pricing Spreadsheet, what is the difference between

Line #14 Congener Specific PCB Scan, and Line #18 209 PCB by HRGC/HRMS (EPA 1668a)? Is the Line #14 Congener Specific PCB Scan an analysis of the same 209 PCB congeners using a low-res method? Can the Service provide a list of the PCB congeners of interest for Line #14 Congener Specific PCB Scan?

Line # 14 is the 209 Congener Specific PCB Scan utilizing low resolution analysis. Line #18 is 209 PCB analysis using high resolution technique HRGC/HRMS (EPA1668a). Yes Line #14 is the same as LIne #18 but utilizes low resulution analytical analysis. The Service does not have a mandatory list of PCBs that are required for the low resolution technique because we are aware that coelutions do occur. Analytical procedures that are used by labs offer differing coelutors therefore please use guidelines from the Performance Based statement of work Section 1.4.3 which is included in the response.

1.4.3 Congener Specific PCB Scan

Offeror will fully describe the methods to be used for analysis and must supply evidence that such methods meet the quality control standards stated in Part 3. Generally methods involve solvent extraction, cleanup, and quantitation of analytes.

An Individual Congener scan shall include quantitation of all PCB Congeners. It is understood that some co-elutions will occur. Offeror should specify which congener co-elutions are expected using their method. PCB congeners will be designated using the Ballschmiter-Zell numbering system.

2. Could you please clarify mandatory and non-mandatory? Page 28 of the Solicitation states that in Attachment D All highlighted (yellow) items are mandatory to be completed. Attachment A page 9 section 1.4.8.12 provides a table of non-mandatory compounds, Volatile and Semi Volatile Organics are included in this table but are also highlighted in yellow in Attachment D.

Volatile and Semi Volatile Organics are non-mandatory. Please see the revised Attachment D.

3. In section 3.8, page 18 of the SOW, the requirement for confirmation of detections by gas chromatography is discussed. Is confirmation using GC with second, dissimilar column an acceptable alternative?

Confirmation performed by Gas Chromatograph using different columns is acceptable. As stated in the SOW a minimum of one sample per matrix has to be confirmed with a total of 10% of samples for the entire catalog. This can be done by Mass Spec or dual Gas Chromatograph analysis.

4. Tissue matrices can require additional preparation and cleanup steps than typical employed for environmental samples in order to meet reporting limits and obtain acceptable chromatography. The additional sample handling and procedures do require additional time. Would the agency consider an extension of 3 to 4 weeks to the due date for the bid in order to allow more time for processing the 9 test samples?

The Service will not consider an extension of 3 to 4 weeks to the due date because of the sometimes found complexity of performing tissue samples. As part of the awarded contract, labs are sometimes asked to perform 20 samples or less within 21 days. These rapid turnarounds are needed by the Service and cannot be extended because the data may be needed for spill response, litigation, cleanup or purchase of land. The performance test samples that you will be shipped are lab generated and therefore analysis should be able to be performed within the 21 day reporting time. No results will be accepted after 5 pm PST on October 4, 2017.