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1.0 INTRODUCTION <br />This 2013 Annual Revegetation Monitoring Report is for the reclamation program at Mesita Hill <br />Mine (DRMS Mine Id # M- 1977 -227) owned by MWCA, Inc.. Mesita Hill Mine is an open -pit vol- <br />canic scoria mining operation encompassing a 201.2 -acre permit area and is located in Costilla <br />County of southern Colorado in the San Luis Valley east of Highway 159 (Sec 26, Township 2 <br />North, Range 74 West of the 6th Principal Meridian). Scoria has a specific market and the mine, <br />which has been in periodic operation since 1948, is currently inactive. <br />The site was surveyed by Ingrid Bamberg, Bamberg Ecology LLC, on June 17, 2013, to identify <br />the current stage of reclamation progress. Revegetation progress, including recent germination <br />of perennials and annuals, and general conditions of the reclaimed areas were evaluated. <br />Since no quantitative revegetation criteria are required for this mine site, the site was monitored <br />using qualitative survey methods for plant cover species composition, and was photographed <br />for documentation. This report discusses the current status of the mine site's reclamation. <br />2.0 SITE DESCRIPTION <br />The San Luis Valley is a desert landscape with vegetation dominated by arid - tolerant shrubs <br />and shortgrass prairie species. Shrubs in the surrounding landscape are generally of a low - <br />growing habit and are dominated by broom snakeweed (Gutierrezia sarothrae), rabbitbrush <br />(Chrysothamnus sp.), winterfat (Krascheninnikovia lanata), and saltbush (Atriplex sp.). Grasses <br />are dominated by blue grama (Bouteloua gracilis); other grasses may historically have been <br />more dominant but appear to have been diminished by livestock grazing. Local land uses, re- <br />stricted by the lack of surface water, are rangeland and wildlife habitat. The annual mean tem- <br />perature is 42.2 °F with an average annual total precipitation of 11.8 "; from rain (9.2 ") and snow <br />(26.0" at 2.6" water equivalent)'. The growing season averages 94 days. <br />The Mesita Hill mine site is a broad, low- relief, basaltic shield volcano with typical slope angles <br />of one to two degrees. The scoria material in this location is only slightly welded and, due to <br />slow market demand, has been mined over the long term. For this reason, the Mesita Hill min- <br />ing operation, which used no explosives, has been relatively undisruptive. The mine's north pit, <br />at about 40 -50 feet deep, is the largest on the property. <br />' Data from National Weather Service, U.S. Department of Commerce <br />1 <br />