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10 compounds such as 502, etc.) (Standard Methods for the Examination of Water and Wastewater, 17th Edition, 1989, Method, pg. 4-25 - 427). 3.4 LABORATORY TURNAROUND TIME As discussed in the first third-party monitoring summary report, the laboratory turnaround time was excessive (nearly seven weeks). Core Laboratories received the samples on March 5, 1993 and the date of the Analytical Report (Appendix C) is May 1, 1993 -- a period of nearly two months. 4.0 CONCLUSIONS AND RECOMMENDATIONS FOR FUTURE SAMPLING - No groundwater samples were able to be collected for this momitoring event because the groundwater pump was not operational. Back-Up parts or a second pump should be kept on site to avoid this situation in the future. - Differences between dissolved and total metal concentrations warrant collection of matched (either filtered or unfiltered, preferably unfiltered) samples for total and WAD cyanide and metals; determine cyanide on both filtered and unfiltered samples from the process points for the nett third-party monitoring. - The cyanide analyses in the process-point samples are unacceptable, especially the WAD cyanide determinations. In many cases WAD cyanide is greater than total cyanide, filtered WAD cyanide is greater than unfltered WAD cyanide, the duplicate analyses are poor, and spike recovery rates are poor for both total cyanide and WAD cyanide. Two strategies are recommended for improving the cyanide determinations in the process-point samples: (1) send the samples to another laboratory or have Core Labs use alternative cyanide methods; and(or (2) have Core Labs or another lab perform a series of experiments (described in Section 3.3) to determine the cause of the analytical problems. - Because of the poor spike recovery rates for total and WAD cyanide, always use one of the unfiltered process point samples, preferably the collection pond, for the laboratory quality control spike analysis. RCG/Hagler, Bailly, Inc