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pH: The pH of discharges from underground workings have exceeded <br />NPDES maximum standards of 9.0 at times. Maximum pH values appear <br />to be stable over time. Minimum pH values may be decreasing over <br />time (8.2 in 1980 to 7.3 today) though still not to the acidic <br />range. <br />THE FOLLOWING CONCERNS WERE NOTED RELATIVE TO RN-02 AND AHR <br />REVIEWS: <br />1. Presence or Absence of Data Prior to 1981: <br />The mine was in operation prior to the start of the <br />current permitting process. The application contains <br />only limited information on background levels in 1981: a <br />single suite of samples on the Colorado River (1978) and <br />sampling for a limited number of parameters for waters <br />discharged from underground in 1980. <br />Please ask the operator if there is any other data, <br />preferably for a full suite of parameters, prior to 1981. <br />2. Presence of Absence of Full Suite Data Since 1981: <br />The 1985 Findings Document predicted that effects of the <br />mine on the Colorado River will be minimal and that <br />"Surface and ground water monitoring will determine if <br />the effects are minimal, as expected". <br />I find no evidence that extensive water monitoring has <br />taken place at Roadside to verify a finding of no <br />significant effect. The current level of water <br />monitoring at the Roadside mine is pretty much limited to <br />standard NPDES parameters. There is evidence that <br />changes to the monitoring regime took place during the <br />1987 Renewal and 1990 Midterm processes but no one in the <br />Division is clear as to what took place. <br />Please ask the operator: <br />a. If there exists, data for sampling of a full <br />suite of parameters for any sites since 1981. <br />b. What changes in water monitoring that have <br />taken place at the mine (exclusive of <br />Cottonwood and Rapids Creeks) since 1981 and <br />when those changes took place. <br />c. For copies of pages left intentionally blank <br />in the permit that relate to water monitoring. <br />