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� r�r • a- '' ' 61 Ip l ~; LEI 1 III V 1 111 FN 1 6 To: LaFarge and Nelson Family From: Aaron DeJoia H -2 Enterprises Date: August 6, 2014 Subject: Nelson Pit Reclamation Recommendations H -2 Enterprises evaluated the reclamation success at the LaFarge Nelson Pit, Near Dacono, Colorado. The reclamation success was reviewed at several different locations within the gravel pit perimeter and soil samples were obtained at four separate locations (Figure 1). In general, the reclamation success across the entire area was very good. In a few places reclamation success was limited and weeds, mainly Kochia, were the predominate vegetation. In other areas reclamation success was adequate but due to the large quantity of bunch grasses and gravelly nature of the soil it visually appeared inadequate, which it was not. Four areas are of greatest concern, North Plot, Middle Plot North, Middle Plot South, and South Plot therefore a reclamation plan has been developed for these areas (Figure 1). The reclamation plan was developed to obtain a self- sustaining native vegetative cover. The following evaluations are based on soil samples collected at the site and a field site visit. Soil Samples: Review of the soil samples collected indicate that the Nelson Plot Middle North and Nelson Middle Plot North locations have soil salinity at greater levels than the surrounding areas, Nelson South Plot and Nelson North Plot. This slight increase in soil salinity is likely decreasing reclamation success in these two areas. In the South Plot and Middle Plot North soil nitrogen levels were extremely high and could be contributing to the weedy plant populations in these areas Soil pH, phosphorus and potassium were at concentrations great enough to support the establishment and growth of reclamation grasses. All other parameters tested appear to beat concentrations that should not negatively inhibit reclamation success at the site. In addition to the soil test grass growth showed variable reclamation success along the length of the ROW. Grass establishment success was dependent on both the slope position (i.e. summit, shoulder) and soil types. The slope position has an effect on plant establishment and growth as slope position changes evapotranspiration rate, infiltration rates, erosion, and exposure to winds. Grass growth was generally the best on less steep slopes that were less affected by the wind and had decreased erosion. To overcome the impacts of the slope position it is recommended that at least 2.0 tons per acre straw mulch be applied to the entire ROW but especially those parts of the ROW that are susceptible to large amounts of wind and water erosion. In addition to straw mulch, it is recommended that the ROW be interseeded or seeded with the appropriate seed mix during the fall seeding window. Visual Soil Inspection: Soil was visual inspected in the areas of concern along with areas that had adequate grass growth. During the visual analysis of the soil moderate medium platy structure was observed in the top 4 to 6 inches of the soil surface. In the areas of good grass growth weak thin platy and moderate fine subangular blocky structure was H -2 Enterprises, LLC • R.oggen, CO 80643 9 P: 303.732.9300 • h -2exom