RENO — Federal land managers have identified a wide range of issues that must be addressed to move forward with a proposal to establish a wild horse ecosanctuary over 820 square miles in northeast Nevada, from the impact on neighboring mustangs, livestock and wildlife to fencing, water supplies and the local economy.The one thing most of the thousands of commenters agree upon is that that the U.S. Bureau of Land Management’s current horse management policy isn’t working.The BLM issued a 228-page public scoping document on Tuesday that it will use to develop a range of alternatives to examine. The effort …