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Based on the construction and cementing details of the disposal well, it appears that all <br />known and possible USDWs aze adequately protected behind the cemented portion of the surface <br />and long string casings; however, the existing cement bond log on the well (run in 1981) does not <br />meet EPA's present criteria for evaluating cement behind pipe. Although the construction and <br />cementing details of the disposal well indicate that all known and possible USDWs aze adequately <br />protected behind the cemented portion of the surface and long string casings, there is an absence of <br />good information on cement conditions adjacent to the casing to ensure confinement of fluids in <br />the injection zone. The adequacy of the cement must be verified by fiuther mechanical integrity <br />testing of the well prior to injection. A portion of this verification has been carried out as a result <br />of completion of a pressure test of the tubing/casing annulus. A pressure test was conducted on <br />the Getty well on November 28, 2001, as a demonstration that this well had been returned to Class <br />II compliance per the rules of the COGCC. This test was conducted using the same procedures <br />outlined in EPA's Guidance in Appendix G and was witnessed by a COGCC inspector. The <br />pressure test demonstrated that the well had mechanical integrity. Prior to commencing injection, <br />a RATS must be conducted to establish the injection profile in the perforations and demonstate <br />that there is no fluid movement out of the injection zone. These mechanical integrity tests must be <br />followed up by a temperature survey after 4 to 6 months of operation as a permitted Class I well. <br />EPA believes that a static value of the reservoir pressure is needed prior to beginning Class I <br />injection. This will provide a beginning point for analysis of reservoir pressure buildup over time. <br />It is also important to obtain information on the well to provide a baseline for future assessment of <br />the condition of the well and to ensure that injected fluid is confined to the injection zone. During <br />and following recompletion of the Getty No. 1-7LW, the following information must be obtained: <br />(a) The operator must obtain a static downhole reservoir pressure measurement <br />prior to commencing injection; <br />(b) Before commencement of injection, the operator must run a radioactive <br />tracer survey to determine where the fluid is going in the perforated interval <br />and to verify that no fluid is moving upward from the injection zone <br />adjacent to the casing; <br />(c) Before commencement of injection, the operator must run a baseline <br />temperature survey fi•om the base of the surface casing to TD to establish <br />baseline temperature conditions adjacent to the casing for comparison with <br />subsequent mechanical integrity testing to detect fluid flow adjacent to the <br />casing; <br />(d) Within four (4) to six (6) months after initial injection, the operator must <br />run a Temperature log, as outlined in the Guidance in Appendix E, to <br />ensure that there is no upwazd movement of fluid behind the casing (see <br />Appendix E for guidance); and <br />(e) Pressure fall-off test: a pressure fall-off test is required for Class I <br />operations [40 CFR § 146.13 (d) (1)] and must be performed on an <br />Statement of Basis for EPA Permit No. CO 10932-04664 Page 9 of 18 <br /> <br />