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<br />I also suggested at that site meeting that upper Deadman Gulch water should be routed
<br />around the dump. We discussed ways of moving the water, including ditching along the thalweg
<br />at the contact of the waste rock and the natural slope to the south. We also discussed piping and
<br />ditch lining. I emphasized that it would probably improve groundwater quality if upper
<br />Deadman Gulch water could be kept out of the waste rock.
<br />Here are some observations about the water analyses. You may wish to examine the
<br />sketch map attached.
<br />Sample GW-97-7-I Level 6 Portal
<br />Sample G W-97-7-II Upper Deadman Gulch -above disturbance
<br />Sample GW-97-7-III Toe seep sump, in trough of lower Deadman Gulch
<br />Sample GW-97-7-IV Lower Deadman Gulch, -3/8 mi d/s spl II, -1/4 mi. above road.
<br />The data indicate a fairly complicated system consisting of three or more sources of
<br />contaminants, and at least one source of clean water. One of the contaminant sources is the
<br />portal water itself; another is likely to be the Level 6 waste rock pile; and a third contaminant
<br />source is implied by several of the element analyses. At these low pH values, not much will
<br />precipitate so it is possible to make afirst-pass evaluation of the results based on an analysis of
<br />element ratios. (However, in general, reclamation specialists should not try this at home.)
<br />Between Stations I and III, Fe, Ni and Zn decrease by about half, sulfate decreases by
<br />about 4 times and Mn decreases 8 times. Ignoring numbers afer the decimal point, Be also
<br />drops by 8x. If upper Deadman Gulch, which is relatively free of all constituents, is the source
<br />of Mn and Be dilution, then it can be said that the portal water is diluted 8:1 by Deadman Gulch.
<br />This would more than account for the dilution of Ni, Zn, Fe and SO,, so those components must
<br />also be coming from the waste pile. In other words, even after an 8x dilution with surface (?)
<br />water, the waste pile still contributes Fe, SO,, Ni, Zn, Al, As, Cu, and Ag.
<br />Between Stations III and IV, Al, Ba, Cu, Fe, and Ni decrease 2 to 6 times, whereas Mn
<br />increases 3x, and Be increases 10x. Overall, the compositions at station IV aze about the same as
<br />at station I, except for Ba, Fe, Mn and Zn which drop by about 2x, 10x, 2x and 2x, respectively.
<br />This may argue for contamination from another source rock similar to the Level 6 waste rock, Fe
<br />removal by precipitation, and dilution from a low metal source. The Be values argue for yet
<br />another water, as the Be cannot dissolve at a pH would simultaneously precipitate Fe.
<br />It can be concluded that while the Level 6 waste rock is evidently responsible for some of
<br />the contamination at the downstream most station, it is not responsible for it all, and there appear
<br />to be multiple (at least 3 and possibly more) sources of pollution.
<br />I would recommend that before we set up a monitoring station for groundwater
<br />compliance we learn as much about the groundwater system as possible from existing
<br />information: i.e., locations of seeps, underground workings, bedrock geology, alluvial
<br />thicknesses, tributary streams, etc. It would not be possible for me, in good faith, to identify a
<br />source of contaminants to any groundwater monitoring point in this system without more
<br />background information. Any information that Mr. Barker could supply would be worth
<br />considering.
<br />Please let me know if you develop more data for this site. Meanwhile, it sounds like Mr.
<br />Barker has elected to pursue a release from the NPDES permit which has been issued for this site
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