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124 <br /> Mangle Regional Plo'�11JW ��� Pro���c�; eIIIoI� r ent c l�f.,� f Irk <br /> mir irtaisrt r:�ura. <br /> Deliverable: <br /> Survey of existing utilities data along with compilation of the information obtained onto the <br /> base mapping plans. <br /> .13 :3 GeotechrflcM <br /> The scope of geotechnical services will include field exploratory work, laboratory testing, engineering <br /> interpretations and evaluation of exploratory and test data, engineering analysis, and technical <br /> recommendations. <br /> Field Investigations <br /> The geotechnical services are for the preliminary engineering stage and that minimal disruption to <br /> certain stakeholders would be appreciated. Therefore, only minimum numbers of borings will be drilled. <br /> Additional borings will be needed for the detailed design stage. No borings will be drilled on Erwin Road <br /> and on the UNC campus. Borings performed from the prior DMU project will be used in their entirety. <br /> For this preliminary scoping and costing effort, boring quantities and average and guideline-based <br /> exploration depths have been estimated based upon the conceptual drawings and tem discussions. Final <br /> exploration locations and boring depths will need to be developed based upon the 30%design drawings, <br /> review/availability of existing data, information learned from field reconnaissance, and local experience. <br /> At a minimum, the borings will penetrate fill and unsuitable founding materials (organic soils, soft clays, <br /> loose sands, etc.), and terminate in competent residual material. Competent materials are those <br /> suitable for support of the foundations being considered. <br /> According to the Conceptual Plans and Profile Drawings, some sections of the alignment traverse <br /> undeveloped wooded areas and will require some amount of clearing, and many sections cross-over or <br /> are close to existing roadways and may require traffic control in some areas. <br /> Subsurface conditions will be explored utilizing traditional geotechnical drill rigs and soil sampling <br /> methods. Low contact pressure tracked drill carriers or a Swamp Buggy may be needed for drilling test <br /> borings within the wetland areas. Standard penetration tests (SPT)will be performed at regular intervals <br /> in accordance with applicable American Society for Testing and Materials (ASTM) Standards. Water table <br /> observation within each boring will be recorded at boring termination and after sufficient time has <br /> elapsed for the water table to stabilize (normally after 24 hours). Borings near existing roadways or <br /> within developed areas may have to be backfilled immediately after completion due to safety concerns, <br /> thereby limiting water table measurement to termination levels only. Other water level observations <br /> (relative moistures, artesian pressure or conditions, etc.) should also be recorded. Unless serving as an <br /> observation well, each borehole will be backfilled or grouted according to applicable <br /> environmental/regulatory guidelines. <br /> The URS Team will subcontract the drilling services to AmeriDrill, Mid-Atlantic Drilling, and/or Trigon <br /> Exploration, subcontract traffic control services to Traffic Control Safety Services, Inc., and will provide <br /> full time engineers/geologists for oversight of the field work and for logging the boreholes. <br /> Surveyors will stake all proposed borings in the field prior to mobilizing to the site, and provide <br /> conventional survey to locate all the borings(x,y& z) upon completion of the field exploration work. <br /> Duriiarn- rainge I iight RaH TrarWt Project � June 2013 �I9 15 DRAFF„ <br />