ARCHIVED REPORTS_TEMPORARY SOIL GAS PROBE PERMIT APPLICATION PACKAGE

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' SOP TO-14A/15 Rev 4 December 2007 ' 16.1 Initial Calibration (ICAL) ' Prior to performing sample analysis,the GC must be initially calibrated. Following a clean blank analysis, at least five levels (only three are required for some regulatory areas)of target compounds along with surrogates and internal standards are introduced into the GUMS system and the total area under each peak ' determined. These values are entered into the software. The computer will construct the calibration curve according to one of several methods. Hardcopy output of the chromatograms should be saved and kept with the instrument throughout the lifetime of the ICAL. The hardcopy output should list the method used to ' generate the ICAL curve. The ICAL is considered valid until the continuing calibration fails or a major change in the instrument operating condition occurs. ' 16.2 Tune/Continuine Calibration (CCAL) The BFB tune as outlined in section 8.2 must be performed prior to analysis of any standards and repeated ' every 24 hours if samples or standards are to be analyzed. The calibration of the instrument is checked prior to analyzing samples and repeated every 24 hours if samples or standards are to be analyzed. The continuing calibration (CCAL)or continuing calibration verification (CCV)is analyzed to check the validity of the ' ICAL. Normally a standard corresponding to the midpoint of the curve is chosen. Response of the compounds of interest must be within that specified by the method (<30%RPD Aith a m axifflufn a f2 401.) for the continuing calibration check compounds (CCCs) for the curve to be valid. If not all compounds are ' of interest only those being analyzed need to be checked. The analyst may repeat a CCV if the CCV does not pass. ' 16.2.1 For work performed under the National Environmental Laboratory Accreditation Program (NELAP) 16.2.1.1 If the second CCV does not pass, it will require two consecutive CCV analyses in order to pass the criteria or a new valid initial calibration. 16.3 Detection Limits 16.3.1 Minimum Detection Limit The method detection limit(MDL) is the minimum concentration of a substance that ' can be measured and reported with 99 percent confidence that the analyte concentration is greater than zero. The laboratory shall establish MDLs for each method, matrix, and analyte for each instrument the laboratory plans to use for the ' project. The laboratory shall revalidate these MDLs at least once per twelve-month period. The laboratory shall maintain proof of the MDL demonstrations (i.e., before project samples are analyzed) and upon request in the format specified in Section 8. Results less than or equal to the MDL shall be reported as the MDL value and/or ' reported as non-detect("nd")with the reporting limit value clearly shown. Laboratories participating in the work effort shall demonstrate the MDLs for each instrument, including confirmatory columns, method of analysis, analyte, and matrix (i.e., water and soil) using the following instructions: Page 20 of 24 1