ARCHIVED REPORTS_TEMPORARY SOIL GAS PROBE PERMIT APPLICATION PACKAGE

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' SOP TO-14A/15 Rev 4 December 2007 ' Zero grade air,Nitrogen or helium is used for preparation of standards and for preparation of laboratory blanks. Primary standards for analytes, surrogates and internal standards are normally purchased from ' commercial vendors and are diluted for use. As of 11/10/04 there is only one manufacturer of gas standards for TO-14/15, Spectra Gases, Branchburg,N.J., although they sell the gases through other supply houses (e.g., Restek) All purchased standards are shipped with certification attesting to their purity and authenticity. ' Each mobile lab and the fixed-based lab performing TO-14/15 shall have notebooks to record standards. Refer to H&Ps SOP manual or the individual notebook for nomenclature of standards. ' All standards are prepared in 6L or greater Summa canisters and stored at room temperature. ' 7.2.1 Standard Preparation Three standards are required to be prepared for Method TO14A/15. The first contains ' the internal standards(Bromochloromethane, chlorobenzene-d5, 1,4-difluorobenzene) and surrogate compounds (Toluene-d8, 1,2-dichloroethane-4, 4- bromofluorobenzene). The second two contain the target analytes. Commercial ' mixes are used to prepare these. 7.2.1.1 Using the Entech can cleaner, clean three six liter summa canisters. Refer to the ' Entech literature for guidance. In general ten cycles of evacuation down to 1000 millitorr and filling with zero grade gas will be sufficient. Evacuate the cylinder to at least 1000 millitorr at the end of the cleaning. Allow cans to completely cool ' before proceeding. 7.2.1.2 Introduce about 20 ul of reagent grade water into the quick connects on each of the three summa canisters to be used. ' 7.2.1.3 Using a gas-tight 100 mL syringe introduce 300 mL of internal standard/surrogate mix @ 1.0 ppmv into one of the 6-L summa canisters. Then attach summa to helium or zero air source and pressurize to a stable 14.7 psi (2 ATM). This will yield a vapor standard containing 25 ppbv of internal standard and surrogate.(Note that there is one atmosphere of pressure in the cylinder, thus roughly two atmospheres of diluent has been added to the standard.) ' 7.2.1.4 Into the second clean humidified evacuated canister, introduce 120 mL of each of the 1 ppmv standard mixes to be used. Then attach summa to helium or zero air source and pressurize to a stable 14.7 psi (2 ATM).This will result in a standard at ' 10 ppbv containing the target analytes. 7.2.1.5 Prepare a second source standard as described in 7.2.1.4 using second source gas standards. 7.2.1.6 Allow 2 hours for equilibration 7.2.2 Standard Expiration ' The primary purchased have been given an expiration date by the manufacturer of one year. ' Page 6 of 24