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f. PHC statement: Inflows to the Somerset Mine are estimated at 235 gpm, TDS 2280 to 3176. I am assuming this refers to the old Somerset Mine, not the Sanborn Creek Mine, so is not applicable at this phase of mining. Inflows to the Sanbom Creek Mine, however, are roughly 50% of that predicted total with TDS of inflow water in the predicted range. g. PHC statement : Discharges to Sanborn Creek will be as high as 425 gpm, with TDS content of 2940. Permitted discharge from the mine was increased to ?000 gpm by Technical Revision 34. The discharge volume peaked at ?000 gpm for approximately three months in 1999, but has since returned to the range predicted in the PHC. TDS of the discharge has been around 3000 mg/1, just as predicted. h. PHC statement: There is little or no potential for significant groundwater degradation, but some potential for TDS impact to groundwater if workings flood and groundwater is discharged. This statement in the permit application refers to eventual filling of the mines after closure. Based on data from the mine discharge in 1999, the indications are that there would be some impact from elevated TDS. I question whether that impact would be to groundwater, however. If the mines eventually fill, the more likely scenario would be that the "overflow" would discharge from the sealed portals rather than entering the very tight rock of the remaining in situ formations. 2. Additional Comments a. Unlike last year, the analyses from surface water sites S-1 and S-2 were virtually identical this water year. No explanation required. b. There was nothing unusual noted regazding flow or hydrochemistry of springs. c. On the tables for groundwater, there is a column for "flow." We presume that refers to depth to water. d. In last year's AHR review a request was made that monitoring proceed at site S-2 regardless of flow at S-1. I[ appears that this wasn't addressed in the 1999 sampling. e. The Division requests that Oxbow Mining amend the water monitoring plan to include those analytes for which receiving stream standards exist for the North Fork of the Gunnison River. These should be part of the regular monitoring program and monitored during the month of August, when flows are low and irrigation withdrawals are still active. Both upstream and downstream North Fork samples should include these analytes along with active discharge points.