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LANG RANCH COMMUNITY PARK DESIGN DEVELOPMENT AND r CONSTRUCTION DOCUMENTS Scope of Servi ee* inclinometer pipe has been selected to help reduce buoyancy griOgnding stresses due to the slurry and/or ground water within the borings. We are planning for Tush -mounted , monuments at the ground surface for access (continued) for inclinometer readings. The baseline readings of the inclinometer can occur usually within about 1-2 days after inclinometer installation. Generally, several readings will be taken to establish the baseline from which all future readings will be compared. We would recommend monthly readings thereafter through the designphase. Once construction begins, readings should be increased to once per week, depending on the mitigation measures recommended for the site and the construction schedule; additional readings may be necessary on a part time basis. Once grading is complete, readings can be changed as necessary. Typically, readings on similar sites occur once per month, bi-monthly, quarterly or another reasonable time frame thereafter. Occasionally, readings may be increased to account for fluctuations at the site due to changed conditions such as heavy rains or strong ground motions from earthquakes. Please Note: The cost estimates provided herein are based on ' estimates provided to us by drillers familiar with the installation ofslope inclinometers. The installation of deep inclinometers (borings approximately >120') require us to use a different type of drill rig than would be used for shallower borings. This rig, a mud rotary drill rig, uses drilling fl uids to help advance the drill bit, because conventional drill rigs either can not reach or can not provide enough down pressure to cut through various anticipated site soils at depth including cemented rock, verb, stiff rock or hard rock, which we do anticipate at the site. The potential disadvantages to a mud rotary drill rig are loss of drilling fluid due'to cracks or voids in the rock, like those that can occur in landslides, among others. LGC has chosen mud rotary because it is less expensive and quicker than other types of -drill rigs or drill bits, i.e., diamond core drill rigs that can reach these depths without as much dependency on drilling fl uids. We also believe there is a moderately high to high potential that the mud rotary drill rig, used properly, will be successful for the anticipated conditions. However, it is possible that an. inclinometer boring may need to be abandoned due to these or other unforeseen conditions at the time of drilling and thus need to be relocated elsewhere onsite or abandoned altogether. Although not anticipated, these potential "unforeseen" costs are not a part of this proposal. PSOMAS Scope of Services I LGC Geotechnical — 37