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Vlfe world request that the amended map depict postmine vegetation types with <br />applicable seedmix denoted. Pastr?ine land use categories could be clarified by <br />including a note on the margin of the map listing the vegetation typelseed mix <br />parcels that comprise each land use type {Pastureland, Cropland, ar Rangelands. <br />Please ensure that text, tables, and the map are all consistent. <br />g. The second paragraph on page 2.ob.4????e}-9 appears to be an outdated relict, as it <br />indicates that irrigated pasture ? be irrigated, and indicates that irrigation design and <br />application rates wil: be submitted to ADM. However, the fourth paragraph on the same <br />page clarifies that the revegetation methods and management for irrigated pasture and <br />irrigated hayland will include irrigation, and further provides details of irrigation design <br />and application rates, along with discussion of other management practices. Please <br />delete or amend the second paragraph on page 9, as appropriate. <br />?o, The seedmix #8 ?Dryland Pasture} mix on page ?.gb.4??}{e}-?o contains an error; the <br />individual components total a seeding rate of 4.8 pounds per acre, not 5.? pounds per <br />acre as indicated. Please amend the seedmix as appropriate. If the same species are <br />used, we would recor?mend crested wheatgrass at 0.8 pounds per acre, pubescent <br />wheatgrass at 2.3 pounds per acre, Russian wildrye at ? .? pounds per acre, R <br />wheatgrass at 0.8 pounds per acre, and alfalfa at 0.? pounds per acre totaling 5.7 <br />pounds per acre, PLS}. RS wheatgrass is a relatively recently developed artificial hybrid <br />of quackgrass and bluebunch wheatgrass. It is seldom used on reclaimed coal lands, <br />and we are not familiar with its performance an dryland sites similar to those at New <br />Horizon. vVe recommend that NRCS be contacted regarding their knowledge and <br />experience with the hybrid, in dryland pasture mixed plantings in the region. If the <br />decision is made to drop R wheatgrass from the mix, rates could be adjusted to ? .0 far <br />crested wheatgrass, ?.7 for pubescent wheatgrass, ? .? for Russian wildrye, and 0.5 for <br />alfalfa {totaling 1?,7 pounds per acre, PLC, <br />1 ? . ?n page 2.0.4{2}fie}-1 ?, the plan far dryiand pasture reclamation indicates that such <br />areas "wil! initially be irrigated by water cannon for the first 3 years to ensure successful <br />establishrr?ent". irrigation rate and timing of irrigation applications are not specified, but <br />apparently irrigation practices are similar to those used for irrigated pasture. Based an <br />results observed at the NH-1 Rice Tract, we question whether the three year irrigation <br />period, with relatively high application rates utilized each year, is beneficial to the long <br />term growth and survival of the seeded species. Relatively heavy irrigation rates for two <br />or three years may favor certain species at the expense of other species in the mix, and <br />without some moisture stress during the early establishment years, the stand that does <br />became established may not be well adapted to dry periods in the early years following <br />termination of irrigation. <br />In our Limited experience with use of irrigation far establishment on reclaimed lands in <br />Colorado, irrigation has been applied only during the initial year of establishment, and at <br />rates intended to supplement nature! precipitation. However this was on deep aeolian <br />sand derived sails in eastern Colorado ?Keenesburg},and the growing conditions and <br />climate difrered considerably from Chase in the Nucla area. At the San Juan Mine near <br />Farmington, New Mexico, conditions maybe somewhat more comparable to those at <br />New Horizon. At San Juan Mine, a two year irrigation approach is used, with high <br />application rates the first year for germination and seedling establishment, and lowered <br />rates the second graving season, adjusted rnanthly as necessary to simulate an above <br />normal rainfall month. Irrigation is terminated after the second growing season. Average <br />annual precipitation at San Juan is 8.?fi inches, so it i somewhat dryer than New <br />Horizon, but the theory and basic approach ray be applicable. vVe have enclosed <br />correspondence with David Clark of the New Mexico Coal Programt which includes <br />excerpts from the San .?uan irrigation plan. <br />5