2008-07-15_REPORT - M1988044 - Laserfiche WebLink

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locations that appeared to be likely deposits. Sometimes it showed good sand, other times it showed nothing. Backhoe pits were established as far south as the affected land boundary would allow and only a couple of little pockets were found. Due west of the former ranch headquarters no sand was ' found anywhere. Another small sand pocket was found west of the road near a small structural fill pit. i At this time, it appears that essentially all of the sand in the original permit area has been depleted and all the other unmined areas contain either no sand or sand of such low quality it would be questionable whether mining it would even make sense. HYDROLOGIC CONDITIONS ENCOUNTERED: No groundwater was encountered in any of the mining pits operated in the past year. Surface drainage, once all the snow?melted in 2007, returned to a fairly normal pattern. No heavy flows were seen in Coal Creek all summer long and any flow that did occur was mainly a superficial trickle. That said, the hydrology of the area did improve greatly in 2007, especially along Coal Creek. Deep soil moisture increased greatly as the snow melt water worked its way down into the subsoil in the uplands and this translated into robust growth of the more deeply rooted grasses. Blue grama, in some places, was one to two feet tall when normally it is little more than about six inches tall. Wheatgrasses and needlegrasses reached upwards of two feet and produced a great deal of seed. Along Coal Creek, cottonwoods showed very little moisture stress and appeared to have good leaf turgidity through nearly the entire summer. Only the very old trees near the edge of the groves continued to show some decline, but even those seemed to sometimes show a youthful vigor. But by the start of the 2008 growing season all of those excellent growing conditions in 2007 had been lost. Subsoil once again became depleted resulting in sometimes deep cracking of the upland soils. Grass and forb growth was weak at best and in most areas showed nothing more than a few leaves and very little flowering. Only very deeply rooted forbs made a fair showing during early 2008. Along the stream channel, stress returned. Although the trees looked good most of the spring, by early July evidence of stress was once again apparent. There are still good outflows in the channel where the groundwater under the sandy stream bed appears, but it is a bit lower and less in volume than last year and stagnated pools are once again evident. Most of the younger cottonwoods and willows though showed good early growth. Wetlands along the stream bottom continued to show excellent condition. If a strong monsoon arrives some good growth could yet occur this year and relieve the tree stress some, but unless it is very strong this year may result in a net loss over last; year's gains. Such patterns, although of concern, are normal in semi-arid grassland and in riparian forest along streams and rivers in semi-arid lands. Thewegetation is well adapted to such conditions and even though long term drought may cause a tremendous decline in native vegetation cover, this vegetation has an incredible ability to gain back a lot of the losses in even a single season. If the plants could not do that then they would not even live there. However, a drought in excess of about 10 to 15 years would basically destroy the vegetation as it would not be able to recover in any reasonable period of time. With such a prolonged, continuous drought of that scale the vegetation would need to rebuild itself and it is likely what would result would not be like what was there before. But it would be even better adapted to survive even more intense drought. That is the way natural selection works. Status report for 2007 (July 15, 2007) Page 4 of 10