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Vantage to Pomona Heights Chapter 4 230 kV Transmission Line Project FEIS Environmental Consequences PAGE 4-5 4.2 VEGETATION AND SPECIAL STATUS PLANT SPECIES 4.2.1 Methods and Impact Types 4.2.1.1 Analysis Methods To calculate impacts to vegetation from the proposed Vantage to Pomona Heights 230 kilovolt (kV) Transmission Line Project (Project), the number of miles traversed and corresponding vegetative cover types for each of the transmission line Action Alternative route segments were calculated. Once the mileage was obtained, the rates of disturbance from the disturbance model were applied to these distances to generate estimates of the number of acres of impact per mile of transmission line by vegetation type. Refer to Chapter 2 for a description of the disturbance model. Federally listed and proposed plant species and designated and proposed critical habitat were analyzed in accordance with the federal Endangered Species Act of 1973 (ESA) and ESA Section 7 Consultation guidelines (U.S. Fish and Wildlife Service [USFWS] and National Marine Fisheries Service 1998). Other rare plant species of concern were analyzed following U.S. Bureau of Land Management (BLM) 6840 Manual guidance for special status species management (BLM 2008). Pedestrian surveys for targeted special status plants were conducted on accessible federal and state lands within the 150-foot wide survey corridor for proposed route segments (Appendix B-3 Special Status Plants Reports). Sections of some route segments and the majority of Manastash Ridge Subroute (MR-1) were not surveyed due to route adjustments that were made following the completion of the pedestrian surveys and additional survey timing being outside the appropriate seasonal survey period. Federal and state lands comprise approximately 43 percent of the total survey corridor for all of the Action Alternatives. The remaining 57 percent is comprised of non-federal (private and county) land and was not surveyed. Of the 1,378.9 acres of federal and state lands within the 150-foot wide survey corridor, 645.9 acres (47 percent) were accessible and surveyed (see Table 3.2-3). As not all land within the 150-foot survey corridor was surveyed, the analysis for special status plants is based upon several assumptions which have been incorporated into Required Design Features (RDFs). First, right-of-way (ROW) clearance surveys on federal land would be completed prior to construction and during the appropriate season for the detection of special status plants in areas that would be disturbed and that have potential suitable habitat for special status plants. Populations of special status plant species would be delineated on Project maps as “Avoidance Areas,” and would be marked in the field prior to the start of construction. If any new populations of special status plants are discovered on federal lands during Project surveys or construction, these findings would be reported within 48 hours to the authorized officer at the appropriate state or federal agency and would be treated the same as currently known populations. In cases where such species are identified, appropriate action would be taken to avoid adverse impacts to the species and their habitats. A Plant Protection Plan would be developed identifying specific measures to protect special status plants. Protection measures could include timing restrictions, altering the placement of roads or structures, and the use of biological monitors to protect biological resources during construction. In situations where impacts to sensitive plants cannot be avoided by construction activities, transplanting of plants would be considered and prior approval from the appropriate land management agency would be obtained. Depending on species and conditions, the transplanting of special status plants may include the following: seed collection, propagation, planting, and supplemental watering for one or two seasons or transplanting and supplemental watering for one or two seasons. There may be undiscovered populations of special status plant species in areas that may be impacted by the proposed Project. The baseline information provided in Chapter 3 has been used to determine impacts to each species and their habitat. Occurrence location information used for this analysis is from geographic information system (GIS) layers as mapped by the Washington Natural Heritage Program