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New Horizon Mine TR-57 <br />2°d Adequacy Review <br />21-Oct-2008 <br />Page 12 of 15 <br />of parameters specified in Table 2.04.9-2, and Table 2.04.9-1 is erroneously <br />referenced. Please delete the entire first sentence of the paragraph, and insert <br />"subsoil " in front of "Sample" in the sentence that follows, in the same paragraph. <br />Item Resolved <br />33. The statement on page (d)-29, that "results of this testing revealed that the Bench 1 <br />subsoil was suitable for all tested criteria" does not appear to be accurate. <br />Attachment 2.05.4(2)(d)-1 shows that one sample did exceed the conductivity <br />standard by a small margin. Also, we do not concur with the discussion in the <br />Attachment 2.05.4(2)(d)-1 report, which indicates that EC is generally run only as a <br />screening tool, and that EC exceedances do not affect suitability of the soil if SAR is <br />not elevated. Elevated levels of conductivity (i.e. salinity) do affect soil suitability, <br />irrespective of individual ionic effects, by inhibiting the ability of plants to extract <br />water from the soil. Please amend the referenced wording in the Attachment. <br />Item Resolved <br />34. A further concern with EC and pH data reported in Attachment 2.05.4(2)(d)-1 and <br />Attachment 2.04.9-11, (which contain largely duplicate reports and data), is that the <br />data reported for these parameters from the second round of sampling taken from the <br />2.5 acre grid, are based on 1:1 Soil:Water extract, rather than the standard, permit <br />specified Saturated Paste extract. Interestingly, in the first round of samples (Samples <br />101 through 106), lab sheets are included which provide EC and pH levels based on <br />both 1:1 and Saturated Paste Extract. The 1:1 extract EC value for Sample 105 (Lab <br />#44950) is 1.94; the Saturated Paste extract value for the same sample is 4.09. This is <br />the sample mentioned in Walsh report as exceeding the 4.0 mmho/cm standard. The <br />Saturated Paste extract value is more than twice as high as the 1:1 extract value, <br />which is the case with all 6 of the samples for which values are reported for the two <br />different extracts. It may be the case that one or more of the second round samples <br />(e.g. SS-21, SS-26, SS-32, and SS-33) would also exceed the standard, if analytical <br />values based on Saturated Paste extract were reported. <br />Please provide lab sheets with saturated paste extract based pH and EC values for all <br />of the samples collected from the 2.5 acre grid. If the lab did not provide Saturated <br />Paste Extract pH and EC analyses for the subject samples, re-sampling of the grid <br />will be required. For any sample sites that exceed the criteria based on Saturated <br />Paste Extract values, the more intensive sampling investigation and mitigation <br />protocol specified in the final paragraph of page 2.05.4(2)(d)-28 will be required. <br />In response to this concern, the operator's consultant, Walsh Engineering, <br />conducted additional investigation including literature search into the <br />relationship between 1:1 and saturated paste extract conductivity values, re- <br />sampling of 8 subsoil sample locations for conductivity analysis using saturated <br />paste extract, and discussion regarding interpretation of the results of re- <br />sampling with Dave Dearstyne, NRCS Soil Scientist. Narrative regarding the re- <br />sampling conducted in response to this item is discussed in amended Attachment. <br />12