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Comment 2: So that brings us to what is being mitigated and what is not in this phase. Mitigating permanent Impacts: Page 14 and 15 mitigation totals are 0.09 acre upland and 0.07 acre riparian. It gets confusing to assign these to offset specific permanent impacts (0.08 upland, 0.14 riparian), in part since they don't provide adequate mitigation for those impacts, for riparian even at 1:1. Also, we suggest mitigation for permanent impacts on the order of 1.5 -3:1 (depending on restoration of non habitat vs. enhancement of existing, etc.). So this means you are substantially shorter than just not mitigating 0.07 acre of permanent riparian impact (bottom of page 16, Table 11 doesn't work) (Hey, for mitigation area one I get 2.6 shrubs for every 10 foot center (not 3 to 5). In contrast, I calculated 3.8 shrubs every 10 foot center for the other 2 areas) Mitigating (Restoring) Temporary Impacts: Comparing impacts (0.28 riparian, 1.31 upland) in Table 10 (p. 18) to the bottom of page 16, it appears that none of the 0.28 temporary riparian impact is being restored and 1.25 of the 1.31 upland temporary is being restored. Similarly, we generally recommend mitigation for temporary impacts at 1.5:1. On page 13 -14 it sounds like restoration areas only get a seed mix. Do they also need planted trees or shrubs? In all cases sizes of trees and shrubs planted should be specified (this may be somewhere in the package). Trees: IRIS MITIGATION AND DESIGN, INC. Environmental Consulting IRIS MITIGATION AND DESIGN, INC. 3450 W. 32nd Avenue, 2nd Floor Denver, Colorado 80211 Phone: 720 - 272 -1985 bleisure @irismitigation.com We also recommend ratios for trees: 1 to 1 might be o.k. for non - natives and below some minimum diameter, but trees impacted above 4" dbh it should go up. The Corps may have standard ratio or Matt could suggest what he uses. Response 2: We will change our mitigation ratio from 1:1 for the permanent upland and riparian area mitigation to a 2:1 ratio (0.04 acre permanent upland area impact will require 0.08 acre upland area mitigation and 0.1 acre permanent riparian area impact will require 0.2 acre riparian area mitigation). We will also increase the temporary upland and riparian area mitigation ratio from a 1:1 to a 1.5:1 ratio (1.3 acres of temporary upland area impact will require 1.95 acres of upland area mitigation and 0.36 acre of temporary riparian area impact will require 0.54 acre riparian area mitigation). These changes will increase the amount of mitigation that will be required at the end of Phase 3 of the project (see Table 1). Schwartzwalder Mine Phase 1 Page 3 October 2011 Response to USFWS Comments