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Vantage to Pomona Heights Chapter 4 230 kV Transmission Line Project FEIS Environmental Consequences PAGE 4-121 Underground Design Option would cross 5.0 miles of Priority Species Regional Areas—the least amount. NNR Alternative – MR Subroute would cross slightly more Priority Species Regional Areas (5.5 miles), but Alternatives A-H would cross between 28.2 and 50.2 miles of Priority Species Regional Areas, depending on the Action Alternative. Overall impact levels for special status wildlife were driven largely by moderate to high sensitivity habitat (predominately sagebrush-steppe), but also took into account documented special status species raptor nests within 1.0 mile of the route segment ROW corridors, documented special status species occurrence points within 0.5 mile of the route segment ROW corridors, and Priority Species Regional Area crossings. None of the Action Alternatives had any miles of overall high impact levels or of no identifiable impact levels. The Agency Preferred and the NNR Alternative - Underground Design Option had the shortest distance classified as moderate impact (29.8 miles), followed closely by NNR Alternative - MR Subroute (30.8 miles), then by Alternative H (34.6 miles), and then Alternative D (38.4 miles). The greatest length of moderate impact levels is associated with Alternative B (51.1 miles). While the NNR Alternative - MR Subroute would impact more miles than the NNR Alternative - Overhead Design Option or the NNR Alternative - Underground Design Option, most of the additional miles would have a low impact level as miles of moderate impact are very similar among the three northern route segments. While the NNR Alternative - Underground Design Option would result in slightly fewer transmission line structures than the Agency Preferred Alternative, the number of structures greater than 0.25 mile from an existing transmission line would be the same and the acres of direct habitat disturbance would be slightly higher. Thus, the NNR Alternative - Underground Design Option did not have different overall impact levels than the Agency Preferred Alternative. A portion of each of the Action Alternatives would be located within the YTC Priority Area of Conservation (PAC). The Agency Preferred Alternative and the NNR Alternative - Underground Design Option cross the shortest distance of PAC (38.7 miles), followed by Alternative A (41.5 miles). The longest distance of PAC crossing by any Alternative is 58.9 miles by Alternative G. The ROW corridor for the three NNR Alternative design options, including the Agency Preferred Alternative, would be located entirely outside of the estimated YTC Sage-Grouse population range, where 95 percent of Sage-Grouse use is expected to occur (based on the kernel density analysis). The eight-mile wide Sage-Grouse analysis area for the three NNR Alternative design options overlaps approximately eight percent of the total estimated 95 percent population range (15,264 to 15,424 acres, depending on NNR Alternative design option). The NNR Alternative design options do not overlap the core range, where 80 percent of Sage-Grouse use is estimated to occur. Recent Sage-Grouse use has been documented near the NNR Alternative (all design options) indicating that these areas are used by Sage- Grouse occasionally, but telemetry data indicate that use near the NNR Alternative is much lighter than areas within the population range. Each of the Alternatives A-H, cross through the estimated Sage-Grouse population range for a substantial distance, (22.1 miles to 25.4 miles, depending on Action Alternative). Alternatives A-H pass through the 80 percent core Sage-Grouse area for distances ranging from 7.4 miles for Alternatives G and H to 10.2 miles for Alternatives A and B. The eight-mile wide Sage-Grouse analysis area for each of Alternatives A-H overlaps approximately half (44 to 56 percent, depending on Action Alternative) of the total estimated 95 percent population range for the YTC Sage-Grouse population. There are four active leks and two inactive leks within four miles of the Action Alternatives. None of the Action Alternatives would be located within 0.6 mile of an active or inactive lek, but each Action Alternative would be within four miles of active leks. The three NNR Alternative design options each have two active leks located between three and four miles away. Alternatives A-H each have four or five active or inactive leks within four miles and one or two of the leks are within two miles of the Action Alternatives. Historic leks (i.e., leks that have not been occupied for at least the past ten years) occur near