2010-11-10_REVISION - C1981008 (2)

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03/18/2009 12:29 9702475104 DM6 DCRANGO OFFICE PAGE 09/21 • _ Ph USDA Critelli. fin rim. farm7at did state that the tntat tapwil criteria were plus subsoil depth must equal m exowd s • t't�r) \ y � 401nches. These used to modify the so il cuimbility critcrio table (Tehle 2.04.9 -2)in the DRMS permit L U mi soil samples during the March 5 sampling event wve within suitable..gels for selected analyl*a and field paramotew. The uppC� two £eel[ of sub. it was inveshgatat, but there was no change m bacrved to dte tool coil pit depth in any soil pit, eiggesdn9 that the soil suitability enter, a would be et in the ihnte to four feet of observed Subsoil at all or must sampling locations_ Re sampfArg for pHandEfecMm( Coardacdviry Comments ftom the DRMS m a letter dined May 28, 2008 revealed that the March 5 subsoil analyses utilized I'.I 0xtrac' for the soil pH and electrical conductivity (EC), rather than the permit -mi itr d paste method for these anelytem. Walsh discussed the situation with DAMS and MRCS pv =4 and dom—'rod that there is apmpostioiwl relationship between 1:1 extract and paste Saunter EC results. A published £*anal& was applied to the I a P C results, and oevcaled that up to four sample points may cxccod the paste EC criteria of 4.0 (samptcs 21. 26. 32, and 33). Based on this, the eight aurylc points that had 1:1 EC higher than 1.2 were mumpisd and andyvod forpane EC (Table 2). WPC pttsurnel crumpled soil at the original sampling points using a 2" hand auger for a tow depth of 24 ". A fiaclion of the extracted sample was placed Ina zip -Inc bag and shipped so Sarvi -Tech Lab 1 Nebraska. The sampling points want le sl d with a e s of twcy -gede Gp6 m match file March 3, 2008 sampling Points. The sampled areas had not yet had ropsoil placed 4 the time ^£sampling. O iril' p eight spl" obtained, two exceeded the topsoil permit c man s of 4. Theft were sample 21 aste E of.34 and sample 32 with a paste EC of 7.33. The sample 32 location is new a top- soil PRO. which may have atPentcd this location. The sampler, noted that as many me {vc aacmpis were comic at sample 32 b Set a complete hole dice to refusal of the hand auger. This suggests that sample 32 may not be rcpresamtative of the subsoil in the area. Disc.."10. The original "nil survey (Tntennoonwin Aca*V[Ce Inventories, Inc, 1998) performed laboratory analyace on three soil profiles within the prime farmland unit sputh of BB Road. Of these thrtz, four individual soil horizons from the approximately 24 -48 inch subsoil interv4 wcxc analyzed. Paste EC ringed from 0.7 to 3 -8, with an svcrage of 1.9. Percent C.CO' ranged from 3 to 36 %, with an average ran etl Cmm 9.1 to / c 31 Corm, or boulders were observed in tlthe horizooa, and lab analysis ofgmvel S - with an ave"ga gravel content of 20,7%. This indicates that the replacement subsoil has higher average pasta EC (3.l %), lower C.CO) (2o /a -4 %), and lower coarse fraction (11 'hall me original tested subsoil. Sample avenge, arc shown on tables 1 and 2. Walsh discussed the impact ef$C on crop, win tal to reuses All Dave Demst c of ce crops are morn scrssinve to .1...0 d P & in topsoil than in subsoil. P.levatd y MRCS, who indicated that established mops but not establishing $C in subsoil can import "mytiled EC than establishing crops.Mr. Dearatl established cmya are gcnaidly more tolerant of not be detrimen yn stated that Subsoil with a poste EC up to 6 would prime fu sion etrim£.robe or alfalf a As Such, eablishing a pane EC criterion of for subsoil in permit may he appropriate. A14 i t Tvi� 5 o E g tan. LLC I c , ' �- leY-.� Skb •I 1 c) 4o be • (Reaised Neu 2009) Attachment 2.05.4(2)(d) -1.4