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Water in the surrounding undisturbed ground water system exhibits a relatively high degree of <br />mineralization, (see Section 2.04.7, Hydrology Description). Well yields are low. Recharge to <br />the local undisturbed ground water system is directly from both the 2nd Park Lateral irrigation <br />ditch (and associated laterals) and excess irrigation water runoff from flood irrigation. The <br />irrigation ditch water and runoff infiltrate and percolate into the weathered zone of the bedrock. <br />Prior to mining at NHN, the 2nd Park Lateral ditch will be diverted through a HDPE pipeline in <br />order to prevent disrupting water delivery to downstream 2nd Park Lateral shareholders. The <br />diversion of the 2nd Park lateral will also result in a "drying up" of the overburden zone prior to <br />mining which will reduce water inflows into the pit. After mining, backfilling, and reclamation <br />has advanced far enough north, the HDPE diversion pipeline will be moved to the original 2nd <br />Park Lateral right-of-way. The structural attitude of the strata, strike northwest — dip southwest, <br />(see Section 2.04.6 Geology Description), will result in post mine irrigation water percolating <br />through the backfill material and migrating to the south along the top of the under -burden (path <br />of least resistance) to the toe of backfill where it will issue as springs tributary to Tuttle Draw <br />(area south of Meehan Draw) and as springs tributary to Meehan Draw (area north of Meehan <br />Draw) as shown in Figure 2.05.6(3)-1 presented later in this Section. This situation is illustrated <br />by the effects of the old Peabody Nucla Mine (see Section 2.04.7 Hydrology Description). Due <br />to the self -draining effect resulting from the structural attitude only relatively small areas (rolls in <br />the floor of the LDx Seam, etc.) of backfill material may be partially saturated. The springs <br />issuing from the toe of the old Nucla Mine (SS #1 and SS #2, see New Horizon 1 permit) backfill <br />material have a calcium magnesium sulfate type water quality with an average TDS of about <br />3,650 and average pH of about 7.0. <br />The normal mixing that takes place as overburden is shot, loaded and placed in the backfill and <br />the overall high degree of neutralization potential of the spoil material will minimize changes in <br />ground water quality. See following discussion on Probable Hydrologic Consequences. Based on <br />the mining experience at the adjacent New Horizon Mine, the physical character of the <br />overburden, and the chemical analyses performed on samples taken from the lithologic units to <br />be affected by mining (see Section 2.04.6, Geology Description), the backfill material is <br />classified as either suitable or non -suitable. The weathered bedrock which is located immediately <br />below the soil horizons (referred to as suitable or free dig material) has been oxidized and is both <br />physically and chemically altered from the parent bedrock. The physical alteration of weathering, <br />(to depths of 25 or 30 ft.), weakens the original bed rock material to the point that it can be <br />loaded directly into trucks (free dig material) without the time and expense of drilling and <br />blasting it. This weathered overburden material is typically light brown in color and sharply <br />contrasts with the underlying un -weathered much stronger light gray siltstones and sandstones to <br />the gray and dark brown to black shale and carbonaceous shale. The un -weathered material is <br />referred to as un -suitable material. The suitable and un -suitable material is handled separately at <br />New Horizon Mine and this method is planned for NHN Mine. The un -weathered or un -suitable <br />Section 2.05.6(3) Page 2 Sept. 2015 (TR -11) <br />