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<br />6.2A <br />Page 20 <br /> <br />Project construction could expose sensitive receptors to increased levels of PM 1 0 (which <br />includes PM2.5) from fugitive dust and diesel exhaust, CO, and ozone precursors from <br />construction activities including ground clearing, excavation, grading, materials handling, the <br />operation of heavy equipment and vehicles, vehicle travel on paved and unpaved surfaces, and <br />building demolition. Construction at the tunnel shaft sites would last between approximately <br />four months (at the Newark Valve Lot) and four and a half to five years (at the Ravenswood <br />Valve Lot). <br /> <br />. Mitigation Measure AIR-l a: BAAQMD Control Measures. <br /> <br />Impact BIO -1: Impacts on saltmarsh harvest mouse and its habitat. <br /> <br />Saltmarsh harvest mouse could be adversely affected near the Ravenswood site by the clearing of <br />vegetation, grading and stockpiling of tunnel spoils, equipment operations, vehicular traffic <br />associated with day to-day operations, and truck traffic associated with off-hauling of tunnel <br />spoils. <br /> <br />. Mitigation Measure BIO-I a: Vegetation clearing and exclusion fencing <br />. Mitigation Measure BIO-l b: Confine construction area; revegetate; prepare sumnlary <br />report <br />. Mitigation Measure BIO-l c: Mitigate permanent impacts on suitable breeding habitat <br />and upland habitat at a ratio of two acres preserved for each acre lost (2:1); rehabilitate <br />temporary impacts on suitable upland saltnlarsh harvest mouse habitat on site at a ratio of <br />1.1 acres preserved for every acre affected (1.1: 1); acquire and preserve an equal nunlber <br />of acres (1: 1) at an off-site location; compensate for impacts on suitable breeding and <br />upland habitats consisting of the restoration of 3,149 square feet (0.07 acre) of <br />pickleweed habitat and 664,814 square feet (15.26 acres) of upland habitat 011 site and the <br />preservation of an additional 668,065 square feet (15.34 acres) of saltmarsh harvest <br />mouse habitat at an off-site location; and restore uplands used for the stockpiling of <br />spoils, construction equipment and supplies <br />. Mitigation Measure BIO-l d: Contractor-education program <br /> <br />Impact BIO -2: Impacts on California red...legged frog (CRLF) and its habitat. <br /> <br />Between Cordilleras Creek and the Pulgas Tunnel Portal, construction of pipeline would affect <br />ephemeral and intermittent surface tributaries of Cordilleras Creek, as well as Cordilleras Creek <br />itself, a perennial stream. In addition, construction activities at the Pulgas Tunnel Portal would <br />occur in close proximity to Edgewood Creek. If present in the vicinity, CRLF could disperse via <br />culverts and surface tributaries during the rainy season into the work areas between Cordilleras <br />Creek and the Pulgas Tunnel Portal, if water remains available in the channels. Project <br />excavations and pipeline construction in this area could result in potentially significant impacts, <br />including mortality ofCRLF individuals ifpresent during these activities. <br /> <br />......:.: :'.'::Mitigation M easure BIO~2:"Survey, capture arid ielo'cate: CRLF;constriicik,iipersbhnef :... <br />training; notification of the USFWS if CRLF are present; trash containment and removal; <br />spill prevention and response procedures; exclusion fencing; and confine construction <br />area. <br /> <br />Impact RIO -3: Impacts on California tiger salamander (CTS) and its breeding and upland <br />aestivation habitat. <br /> <br />Suitable breeding habitat and summer aestivation habitat for federally listed CTS is present at the <br />Newark Valve Lot and at the seasonal pools near the intersection of Willow Street and Enterprise <br />Drive. Potentially significant impacts could result from the direct disturbance of CTS or the <br /> <br />10 <br />