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instances substantially increase soil strength. Lime is somewhat soluble in water; hence, care must be exercised in its use. The City of Delta performed a chemic~l analysis on surficial samples of the lime material taken in and around the northeast port:ion of the sewage lagoorj. The test results indicated that the five samples cQntain approximately 3 to 4 percent by weight of 'organic material. Discussions with t:he city engineer indicate that the depressions 10catE,d north of the lagoon m<lY contain higher concentrations of organics because direct iashing of the sugar beets occurred in this area. It is :also believed that the highest concentrations of organic matt;er are located close to the sugar beet processing plant located about 1,000 feet east of the proposed fish pond. Lime waE',te used under foundations has, the potential of settling when loaded due to compressibilit;y of the organically contaminated lime and due to potential solution of some of the lime itself. Therefore, the placement of structure foundations on this material sl10uld be avoided. If structures must: be placed in an area of lime fill, the lime material should be removed from dire~tly beneath the foundation, and the foundation should be Qverexcavated. General guidance for removing the lime wa~te is as follows: The over-excavation width should equal the footing width plus 4 inches on both sides for footings ~ feet wide or less or plus 6 inches on both sides for footings over 2 feet wide. The excavat:ion material should be replaced with engineered material free of high plasticiiiy clays and silts. Some lime wast:e could be used as engineered fill (if its use is unavoidable), provided the following restrictions are met. Organic content in the lime is less than 4 percent by weight and the tot:al amount of lime waste ,in the soil mixture does not exceed 20 percent by tot,n volume. Structures with foundation bearing pressUltes greater than 1,000 PSF require a site specific foundat~on investigation. Explorations for t.hese structures should J:le of sufficient number and depth t.o identify lime waste or other unsuitable material zones, and within the zone of influence for the imposed loads. Material used for embankment construdtion at the fish pond or along the Uncompahgre and Gunnisori Rivers should be free of high plast.icity clays or silts whijch are difficult to place and desiccate or crack upon drying. Any material which will be used as an impervious blankE\t should have a K< IX10-6 cm/sec. The lime waste mixed in sdil should not exceed 20 percent by total volume, and thEj organic content should not exceed 4 percent by weight. GEjneral guidance on material types best suited for levee and dike embankments consist of lean clay, sandy clay, sandy silty clay, clayey sand, and silty sand. 24