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I I I I I I I I I I I I I I I I I I I C. -2- of wetlands-type vegetation running generally parallel to the river. The area in lot 4-5 immediately adja- cent to the river and the area in lots 2-4 lying be- tween the wetlands bands are slightly elevated, and drier with grass and sagebrush cover. Most of the upper bench area is presently irrigated hay meadow. The river bank slopes fairly steeply down to the level of the river channel. Most of the site is open and grassy, except for the wetlands vegetation mentioned above, a fringe of willows, cottonwoods, and some pine along the river, and scattered pine in lots 4 & 5. Lot 5 has an old railroad embankment running northerly through the lot. The southwest tip of Phase 2, adja- cent to CR 620 and the Colorado River was used for disposal of excess soils resulting from the trout pond excavation in early 1984. B. SOILS Ground Engineering Consultants, Inc. performed soils exploration and testing at the site in October 1984. Their report is included as Appendix 'B'. Their work generally consisted of excavating seven test pits at the proposed homesites and ground water monitoring. The soils were found to be substantially river allu- vium. Soils in the upper bench sites were silty to clayey sands and gravels. Soils in the lower bench sites were very clean sands and gravels. Both soils have suitable construction properties. Surprisingly, ground water was encountered in only one test pit, at building site 4; after 10 days it had risen to 6.5 feet below surface. The soils technician did not detect any staining, etc. of the soils to in- dicate the limit of higher ground water levels. How- ever, observations of the site during spring and sum- mer definitely show standing water in the wetlands areas. It seems, therefore, that the water levels visually observed are related to spring snow melt and summer irrigation, and that the relatively free drain- ing soils allow water levels to drop rapidly later in the year. Although the soils report is not definitive in this respect, we recommend that all house founda- tions be designed based on a probable high ground water level. 100YR FLOOD PLAIN Rocky Mountain Engineers, Inc. has performed a Flood Study for the Colorado River at the Phase 2 location and the study is included as Appendix 'B'. This is a difficult study, since projections of flood flows at the site are dependent upon evaluation of Granby Res- ervoir conditions and operating procedures. Granby Reservoir is not a flood control facility, and its operator, the United States Bureau of Reclamation, has