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Page 4 • • Furthermore, examination of the wetland a short distance from the structures that appear to have been installed by ABI, shows that such a high production is not likely and has not been the case for any extended period of time for a very long time. At a rate of 25 gpm that would be a production of about 40 acre feet of water per year. The wetland this spring supports covers less than 1 acre and the core of the wetland where emergent vegetation exists around a small pond covers only a few thousand square feet. If water input was in fact at the rate of 40 acre feet a year this wetland would be many times larger than it is. There is marginal evidence that at one time the wetland extended further down the drainage, but based on the fact that the reduction soils typical of wetland areas are no longer present, but appear to have been there in the past, and the face that the hydrophytic vegetation has almost totally left the drainage below the wetland, indicates that the wetland was probably larger about 50 years or so ago. Residual hydric soils often remain for decades after the hydrophytes disappear. Based on the typical pattern exhibited in declining wetlands, it is possible that this spring produced 25 gpm decades ago, but certainly does not produce that volume for any extended period of time today. In conclusion, it appears the 25 gpm production is a rather old number and is not representative of current or even recent conditions. Today, based on the dimensions of the wetland and the kind of piping facilities present at the spring, this spring might produce 10 gpm for a short while during the spring and perhaps a little more after a very wet winter. But during most of the growing season, based primarily on the size of the wetland, it is unlikely the production exceeds 5 to 7 gpm. It could be argued that the throughput in the wetland is high with the water sinking into a cavern and thereby restricting the dimensions of the effective water that can support the wetland. Unfortunately, this spring is in a shaley sandstone that does not characteristically produce caverns. Also stagnation and dense algal growths in the wetland indicates a slow throughput. If it was a high throughput, stagnation would not occur because old water would constantly and rapidly be replaced with new water. Concern B.2.: Potential influences on spring. Response: First of all, the spring is about 250 feet lower in elevation than the Phase 1 area. Second, the mining will generally be at least ahalf-mile from the spring and even if mining extends all the way to the south side of Phase 1 it will still be about I/3 of a mile from the spring. But most important is the structure of Table Mountain. Table Mountain is composed of several thousand feet of sedimentary rocks that dip gently to the south and with little deformation evident, other than the general tilt of the mountain. The top of the mountain is capped with the quartzite and presumably that is why the mountain is as high as it is. The quartzite protects the top of the mountain thus reducing the possibility of height reduction through erosion where the quartzite is not present. The quartzite itself is highly impermeable, although certainly a little water seeps down through the deposit. There is little evidence of seeps or wet spots at the interface of the quartzite and the underlying sandstone. So, certainly not much water enters the mountain structure through the quartzite. Underlying the quartzite is the remainder of the Dakota formation which is a porous sandstone. Under the sandstone is the upper part of the Morrison (a fairly dense shale) and then the sandstone portion of the Morrison. This is followed by the Lykins sandstone which is mainly a siltstone, sandstone, and very low calcium limestone. The spring appears to be located at the interface of the bottom of the Morrison and the top of the Lykins, although it could also be in the sandstone part of the Morrison. Other springs (actually seeps and wet spots) might