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11 interfere with the cyanide determination, and it is possible that the green mat-like material could contain these constituents. The composition of the precipitate should be determined so that potential analytical interferences can be identified, and in the interim both filtered and unfiltered samples should be collected for determination of total and WAD cyanide. Samples that have cyanide concentrations above detection should have nitrate+nitrite and fatty acid determinations. Additionally, quality assurance/quality control (QA/QC) procedures such as a cyanide spike recovery analysis should be performed qn samples from the collection pond to determine if anaiytical-interferenc;es are present 3.4 Laboratory Turnaround Time The laboratory turnaround time was excessive for this sampling trip. Core laboratories received the samples on November Z5, 1992, and the third-party sampler did not receive the final analytical report until January 11, 1993, resulting in a laboratory turnaround time of nearly seven weeks. This lengthy turnaround time makes it impossible -to sample on a monthly basis, because the third-party monitor must spend time evaluating the analytical results for preparation of the summary report, and DMG and BMRI must see the report and discuss it before the next round of sampling. Core Laboratories was iQt the process of moving its laboratory during this period, which included the holidays, and they have promised that turnaround time in the future will be a maximum of four weeks. If Core cannot meet this requirement for the next round of samples, either anther laboratory should be retained or the MOU should be changed to reflect the increased laboratory turnaround time. 4.0 RECOMMENDATIONS FOR CIiaNGES IN THE SAMIPLING AND ANALYTICAL PROTOCOL 1) Place a filter in the barrel filtration device when collecting nhe rinse blank. 2) For field parameters, make sure that readings have stabilized before recording measurements. 3) All field parameters, including dissolved oxygen and specific conductance should be taken at the process point sampling locations. 4) Check calibration of field instruments after 3-5 samples are cpllected and after collection of a sample that differs significantly from the following sample. RCG/ITagler, Bailly, Inc.