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f <br />-l <br />The next issue to elaborate on is the apparent quality of the Bench 1 Substitute Subsoil and how <br />it compares to the original Darvey-Bari subsoil that existed on the Morgan property prior to <br />mining. The only direct comparison made between the Darvey-Bari subsoil and the Bench 1 <br />Substitute Subsoil is in the Walsh Report on Subsoil Suitability, February 2008 (revised July <br />2008), Attachment 2.05.4(2)(d)-1 of PR-06, summarized below: <br /> Average Paste EC Average Average Percent Average Percent <br /> (mmhos/cm) percent Coarse (Rock) Coarse (Rock) <br /> CaC03 Fragments <3" Fragments >3" <br />Darvey-Barx 1.9 17 20.7 0 <br />Subsoil <br />Bench 1 3.1. 2-4 5.89 6.37 <br />Substitute <br />Subsoil <br />Land 4 - in top 40 inches No 35 0.1 <br />Capability of soil Standard <br />Class Ile <br />-Limits <br />According to the Walsh Report the Bench I Substitute Subsoil does not meet the Percent Coarse <br />(Rock) Fragments >3" limit of 0.1 % for Land Capability Class Ile soils (fifth column of above <br />table). This soil physical property has a direct influence on the "Available Water Holding <br />Capacity" of the soil, an important factor for crop production. The use of Exhibit D, PR-06 <br />Table 2.05.4(2)(4)-IA "Spoil and Soil Suitability Criteria (Morgan Prime Farnland)(Revised <br />with NRCS and DRMS 2010)", to make comparisons between the Darvey-Barx Subsoil and the <br />Bench 1 Subsoil Substitute is misleading. All the table does is list minimum threshold levels for <br />meeting Prime Farmland designation, of which both the Lift B topsoil (Darvey-Barx Subsoil), <br />and East Area (Bench 1) Subsoil Substitute do meet. The table does not say that the two soils are <br />equal in nature or quality, only that they both meet the minimum threshold criteria for Prime <br />Farmland Soil. Mr. Dearstyne in his November 16 letter explained the difference between Prime <br />Farmland soil criteria and Land Capability Classification Ile soil criteria. They are not the same; <br />the Prime Farmland soil criteria have a much lower threshold level than the Land Capability <br />Classification Ile soil criteria. <br />When I was asked to review PR-06, particularly the soil reclamation practices, I was under the <br />assumption that the reclaimed soil had to only meet Prime Farmland Criteria, which it will, <br />provided the Walsh Report is accurate and the soil handling practices outlined in PR-06 are <br />followed. Therefore, I did approve PR-06 as written on October 1, 2010. 'But Ms. Turner's <br />question is asking if the Bench I Substitute Subsoil is equal to in nature to the original Darvey- <br />Barx soil. The short answer to her question is no, it is not! This is based upon two criteria for <br />class II soils (which the Darvey/Barx soil in this map unit were mapped and classified as). First <br />surface rock fragments greater than 3 inches in diameter cannot exceed 0.1 percent by volume. <br />Second, EC values in the top 20 inches cannot exceed 2 and cannot exceed 4 in the top 40 <br />inches. In addition, according to the San Miguel Soil Survey Area. report under Engineering <br />Index Tables, it shows that Barx soils have 0 percent rock fragments greater than 3 inches in all <br />horizons, and 100 percent passing the number 4 and number 10 sieves (i.e., no particles greater <br />than 2mm and less than 3 inches in diameter - gravel). I also stand by this analysis and my