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HDR Engineering, Inc. Law Proposal No. 267SSA June 13, 1988 Our understanding of the project information has been obtained From letters dated May 11 and June 9, 1988, from Mr. Paul Watson and a proposed roadway plan and profile and NCDOT "Guidelines for Geotechnical Activities". Proposed Scope of Services We propose to drill twelve soil test borings (AST~! D 1586) extending to depths of about 10 to 40 ft below existing grade within the area of the proposed roadway (260 ft estimated total footage). We also propose two auger borings in the proposed spillway area.to obtain bulk samples For laboratory CBR testing. Based on the earlier boring data and that the roadway will be mostly an embankment fill, we have not budgeted any rock coring. The data obtained from the borings will be used to assist us in our evaluation of the subsurface materials for support of the proposed roadwa~ embankment and for general excavation conditions. Based on our previous work, access to the proposed boring locations will require the use of all-terrain drilling equipment. We understand that tree cutting is not permitted at this time but we anticipate some tree cutting to be required if boring locations are to. be kept within the proposed roadway. We would be agreeable to discuss alternate access routes with HDR and property owners prior to the start of drilling. Difficult access and layout time will be charged in accordance with the attached Fee Schedule. We propose to obtain undisturbed samples of soft foundation soils in areas of proposed deep fill for laboratory triaxial shear testing. Consolidation testing of soft foundation soils had seen done during the earlier exploration. Shear strength parameters for the proposed embankment soils are available from the exploration for the proposed Coddle Creek dam. We also propose to conduct 2 laboratory CBR tests on remolded samples o£ potential borrow soils. Soil classification tests (grain size end plasticity) will be performed on representative samples of each soil strata encountered. As requested by HDR. we propose to drill two soil test borings (ASTM D 1586) extending to depths of about 40 ft below existing grade on the western end of the proposed ezbankment dam. If the'two new borings encounter colt/loose soils, undisturbed samples will be obtained for laboratory consolidation testing. If such soils are not encountered at the new borings, we will obtain an undisturbed sample of compressible soils from the'ares of previous boring D-2. Also, we propose to conduct a falling head permeability test in the zone just beneath the soft/loose soils to help determine if two way drainage is probable. The results of our work will be submitted as written engineering reports presenting our geotechni~al recommendations and soil parameters for use in design and site preparation for the proposed roadway and dam. Our reports will also describe the testing prodedures and present the test data in accordance with NCDOT requirements. The borings and laboratory t~pting done for the earlier exploration will be incorporated into the final report. All of our work will be supervised by a senior registered professional engineer specializing in geotechnical engineering. The assessment of site environmental conditions or the presence of pollutants in the soil, rock or ground water of the site is beyond the proposed ~cope of Lhts exploration. 2 LAW ENGINEERING I