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00 0"> o o o -:.=:> Chapter II - DESCRIPTION OF ALTERNATIVES The No-Action Alternative is discussed below, followed by viable membrane and concrete lining construction alternatives, and other alternatives which were considered but eliminated. In response to public input on the draft EA, modifications to the canal designs for membrane lining alternatives have been made to reduce the amount of fee land acquisition that would be required and to avoid impacts to existing bridges. policies for associated actions concerning management of the canal corridor have also been developed and described. These actions involve the fencing of the U.S. property lines and granting permits for existing qualified access across and/or along the canal. In addition, any currently reserved ROW under the 1890 Canal Act along the last half mile of Reach lB and in Reach 2, could be purchased as fee title lands. Finally, a comparative summary of the alternatives and recommendations for each reach are presented. No-Action Alternative AS discussed in the FEIS and in this EA, under the No-Action Alternative, Reaches lA, lB, and/or 2 would not be lined, and the incremental reduction in salt loading for the respective reach(es) would not occur. However, as future funding allows, the associated actions described for all the alternatives would still be implemented. These include eliminating existing unauthorized uses of U.S. property such as encroaching structures; and fencing both the north and south boundaries of U.S. land to protect the Federal facilities, increase public safety and to reduce future encroachment. Right-of-use permits authorizing access to and from adjacent parcels would be issued to adjacent landowners currently using certifiable bridges or the existing canal O&M road for qualified access. Membrane Lininq Alternatives Three viable alternatives for membrane lining the reaches of the Government Highline Canal are presented and discussed. Membrane lining consists of a flexible polyvinyl chloride (PVC) membrane covered with 18 inches of sand and gravel. The 8l-foot top width of the canal would be greater than the existing 45- to GO-foot U- shaped canal width because membrane-lined canal sections require 2.5:1 sideslopes. This slope prevents the sand and gravel covering the membrane from sloughing off into the canal. Modified Alternative Ml - Under Modified Alternative Ml (Membrane 1), a particular reach would be membrane lined as described above and in the FEIS recommended plan, 15 to 25 feet of additional land would be purchased as fee lands. In some areas no fee land acquisition would be needed. These fee lands would be located 9