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D. Soil Erosion Potential <br />The Erosion Risk Management Tool (ERMiT) model was used to determine the expected rates of erosion <br />from burned and unburned hill -slopes within the burned area. ERMiT runs for a variety of slopes, <br />vegetation types and burn severities within the burned area are outlined in the High Park BAER Soil <br />Resources Report. <br />Eighteen scenarios were selected geographically by ownership (US Forest Service land, private, state <br />and /or county), burn severity (high, moderate, low), and cover (forest, grassland, shrubland). Slope <br />gradients and hill slope length were determined for each scenario using Geographic Information System <br />(GIS). Rock content and surface texture was obtained from the soil survey. The data were then entered <br />into ERMiT to obtain the amount of sediment delivery expected from unburned (pre -fire) and burned <br />areas (post- fire). <br />Erosion potential within the burn ranged from less than 1 ton /acre pre -fire to 23 tons /acre post -fire. This <br />estimate was based on soil burn severity, slopes and ERMiT modeling as shown below: <br />ERMiT inputs: <br />Soil Burn Severity/ <br />Scenario <br />Hillslope <br />Slope <br />Slope <br />Slope <br />(tons /acres) pre -fire <br />Rock <br />Vegetation type <br /># <br />Horizontal <br />% <br />% <br />% <br />Texture <br />content <br />Hi h /Shrub land <br />3 <br />Length ft <br />top <br />middle <br />toe <br />2 <br />/o <br />High /forest <br />1 <br />700 <br />60 <br />30 <br />10 <br />extremely cobbly <br />35 <br />Low. <br />/Forest I <br />7 <br />0.88 <br />4.95 <br />.... <br />Low /Rangeland <br />8 <br />oamy sand <br />.... . ......... _ ......... .......... ..... ............................... <br />0.63 <br />High /rangeland <br />2 <br />700 <br />30 <br />10 <br />10 <br />ery gravelly coarse <br />35 <br />andy loam <br />........................._....................... .. ..............................High <br />/shrub land <br />3 <br />500 <br />_ <br />20 <br />10 <br />ery gravelly coarse <br />35 <br />andy loam <br />Moderate /forest <br />4 <br />1000 <br />0 <br />_._.- ..._.._ <br />40 <br />, <br />20 <br />........................... .................. ............................... <br />coarse sandy loam <br />....................... .... .... <br />35 <br />- <br />Moderate/ rangeland <br />5 <br />900 <br />60 <br />30 <br />10a <br />............._......._....................................... <br />Ivery <br />dy loamy coarse <br />35 <br />Moderate/ shrub land <br />6 <br />400 <br />40 <br />[ 20 <br />10 <br />dandy loam <br />I 35 <br />—. <br />... .........._.__..........._J. <br />-- <br />............ _ _ <br />...._....... _ . . .. .............................1 <br />...... ...... ..... ..- . <br />eamcobbly sandy <br />Low /forest <br />7 <br />400 <br />40 <br />20 <br />10 <br />35 <br />Low /rangeland <br />8 <br />100 <br />30 <br />10 <br />0 <br />oarse sandy loam <br />............................ ............................... <br />5 <br />Low /shrub land <br />9 <br />600 <br />20 <br />10 <br />�xtre mely cobbly <br />15 <br />40 <br />loamy sand <br />ERMiT outputs: <br />Soil Burn Severity/ <br />Scenario € <br />Sediment delivery <br />Sediment delivery (tons /acre) <br />Vegetation type <br /># <br />(tons /acres) pre -fire <br />post -fire <br />High/ Forest ".. I <br />1 ' <br />1.4 <br />15.91 <br />Hi h /Ran eland <br />. /Rang eland <br />49 ..... ... <br />Hi h /Shrub land <br />3 <br />0.7 <br />4 84 <br />1._.. ..._., <br />Moderate /Forest <br />4 <br />2 <br />9.69 _....... <br />Moderate /Ran eland <br />Moderate/Rangeland <br />5 <br />1... <br />1.65 <br />22 .9 <br />Moderate /Shrub land <br />.... ' <br />6 <br />0.65 <br />.. 10.95 <br />Low. <br />/Forest I <br />7 <br />0.88 <br />4.95 <br />.... <br />Low /Rangeland <br />8 <br />0.14 <br />0.63 <br />Low /Shrub land <br />9 <br />3.75 <br />9.84 <br />High Park Fire Emergency Stabilization Plan Page 5 <br />