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1 •1 ~~ ~~ points, and, for that matter, the values for total iron and total manganese, are high by a factor of at least ten. Much more plausible explanations for these anomalous readings are errors in measurement, errors in reporting or the after effects of a small, localized mud slide. These data are probably not representative of the general water quality data at the mine site and should be disregarded. Page 4-222 should be revised to include only the more plausible explanations for these suspect readings. The second statement was "Some increase in TDS is expected from runoff from the disturbed area, but the existing data are not conclusive whether this has occurred." OSM was concerned that the data being gathered may not be enough to form a conclusion concerning TDS. The Division has reviewed the above statement and believes that there is no problem with the water quality monitoring program at Trapper. In this particular case, the above-quoted statement was made in early 1987 and does not represent a comprehensive analysis of the TDS levels at the monitoring sites. Such an analysis can be found in the 1987 Annual Hydrology Report, on pages 5-2 and 5-3, and in Figures C-20, C-22, C-24, C-26, C-28, C-30 and C-32. Later Annual Hydrology Reports also have a more comprehensive analysis of TDS levels. The Division advises the operator to revise this paragraph on page 4-222, using the water quality analyses found in the Annual Hydrology Reports. 2. The Probable Hydrologic Consequences (PHC) section in the permit application seemed sparse, according to OSM. OSM believed that this section should be expanded to include more discussion, including hard numbers. It was also believed that the PHC should contain predictions of the effects of mining on springs, natural and spoil. The Division believes that OSM has made a valid point. However, part of the problem may be that the PHC information is not in one, continuous location in the permit, but, rather, interspersed with operational information. For instance, the permit application does contain general predictions of postmining spoil spring water quality. However, the discussion occurs in two different places, starting on page 4-227 and again on page 4-234. The Division recommends that the permit application be reorganized so that all of the PHC information is consolidated in the permit. In addition to reorganization, the Division also requests that Trapper expands upon the discussion in the PHC. All of the topics listed in Rule 2.05.6(3) need to be discussed fully. Some discussions that need to be expanded upon are the projections of water quantity and quality impacts of surface