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class 11 soils can have no more than O. I percent of rock fra greaicr [Bali 3 im:h2s in the surface horizon. Prime farmland can have no more than 10 percent rock tragmerim greater than 3 1 inches in the surface layer. Several other important parameters such as available water holding capacity permeability. FC. and texture are also more limited in range in class 11 soils than in Prime Farmland. It is also important to note that the capability class oC lie best captures the properties. advantages. and limitations for agricultural purposes of the Barx and similar soils rather than the simple designation of Prime farmland. Also, it is important to note that within the surface and subsoil ot't [iarx soil rock fragments do not exceed 0 percent (see Engineering Index Properties table in the San Miguel ..Ikrea Soil Survey for map unit 14). The next pan ofour visit Involved going onsite to the area of consideration. Several areas were examined. The first was a cut-bank along the edge of the original farm ground. A very fine sandy loam surface (Ap) (all textures determined by hand) was noted along with a sandy clay loam arp n with accumulations of ,,-illic (Bt) followed b a silty clay loam horizo calcium carbonate (Btk). Control section textures Nvere within the fine-loamy 0 9 to 35% clay) class and would be representative of the Barx soils. No rock fragments were noicd \kithin the soil layers examined. The next site involved stock-piled material labeled OBI. Fh1s particular pile contained numerous r(vk fragments (visually estimated to be bev,% cen 3 and 50 percent by volume) tip to and including boulder-size (greater than 24 inches In dlainLLter), Color HOYR as opposed to 5YR) and texture (Clay-heavy Clay loam greater than 35 alp iii, with rock fragments indicated that this material %Nas from a difTem-sit source than subsol I parent material for Marx_ Salt crystals of undetermincd kind were also observed. We nCXj toured several other stock piles located on the site. Some of these were labeled 31, 0131. and one pips was labeled AL The piles labeled BI or OBI varied in color. texture. and rock fragments. The redder (5YR) material was similar in texture to Bar\ soil ranges but did contain 0- to 10 percent rock fragments (visual estimate), The other OB piles were graver in color (I OYR). heavier in texture (more clay)_ and contained from 5 to 25 percent rock fragments (visual e�timatc). Much of the surfaces of the: OBI piles also had undetermined salt crystals ofsome kind- Based on these charaLteristics, this material most likely was from another source than the parent material that Rare soils derived from. The last area examined was identified by the farm operators as a location on the property being reclaimed by the mine. The replaced subsoil appeared to be derived from another source. i.e... not Barx, as noted previously. This 1 contained rock fragments up to and including boulder-size and varied from 5 to 25 of4w, ,] % en location (visual estimates). When I tried to excavate this material. it was very difficult. It had been compacted as was evidenced by the platy structure observed, This material at the site also contained greater than ay (fine, hand estimate)- We then proceeded to an area where topsoil material had been placed over this .. other" material. Here the substratum material had been apparently rip and loosened somewhat. - 1 - he topsoi layer appeared to he betr,veeri 18 to ' )0 inches t hic k (visua esti rnate) along the contact face with the underl,, ing material exposure. The topsoil portion appeared to have been disked. Surface fragnients occurring in this reclaimed topsoil. greater than 3 inches in size, was visually estimated io he around 2 or percent. Mr. Morgan indicated that many of the larger rock fragments had a] rcad-, been ' out" and removed by himself and Joellen. Based on the [imitcd obscr% ations and estimates made on this site. several possible, conclusions can be dra�%n. It should be noted that these conclusions are not based on any chemical data anti deli not include permeability measurements. These properties arc of importance to both Prime Farmland and Capabilit class determinations. First. there is a significance difference bet%N cen ?rime Farmland and its properties and "break points" and the Capability Classification properties, parameters. and lwak point-, of He given to Barx soils in map unit 14. Second, the first stock pile of material noted. above, OB I, would possibly/probably not Tuesday, November 16, 2010.max