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.. <br />Memo to Dave Berry <br />Bowie No. 2 Additional Geotech Study <br />page 7 <br />Page 4 <br />In their original geotechnical engineering report, Maxim Technologies <br />reported that several soils exhibited volumetric expansion (under 500 psf <br />fixed loads) of up to 13 percent, correctly termed "highly expansive. <br />Further, the author appropriately commented; "Clearly, most of the clays <br />on this site would be considered sensitive to loss of strength and/or <br />volume change upon increases in moisture content or pore pressure. In my <br />earlier adequacy memorandum I observed; "...upon reclamation of the <br />surface facilities extensive soil materials will be unavoidably exposed to <br />the elements. In their reclaimed configuration, swelling and low-strength <br />soils will be unconfined and exposed to extensive moisture. In this <br />configuration materials will exhibit their swollen, deteriorated `ultimate' <br />plastic regime strengths. Reclaimed facilities will have to be designed <br />and analyzed with this fact in mind. The appropriate material strengths <br />will have to be used in determining the slope stability of reclaimed <br />facilities, cuts and fills." <br />Further, the author observed that the expansive soil materials will likely <br />significantly degrade in performance if wetted. One of the anticipated <br />wet spots in which Maxim projects the likelihood of encountering <br />significant ground water is in the area of the portal bench, where the <br />highest cuts and slopes are projected to be constructed. In my earlier <br />adequacy comments I commented; "...extensive detail will have to be <br />provided to describe the collection and diversion of these ground waters <br />and the long term stabilization of the potentially effected 80 foot high <br />cut slopes and 50 foot high fill embankments. This will constitute both a <br />significant operational facility and reclaimed configuration design <br />challenge." <br />In the conclusion of this additional geotechnical study, Maxim <br />Technologies states; "We do not believe expansion of the reclaimed slope <br />fill to be a concern for the longterm stability of the slopes." This totally <br />unsupported conclusion, which appears in contradiction to Maxim's earlier <br />