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• The only phreatophyte vegetation at the site -cottonwoods, willows, and water-demanding grasses - is located within a few feet of the slope toe; • The highwall of the Metcalf Pit, located west of the proposed site on the slope edge of the upper terrace, has no history of groundwater emanating from it; • The Spring Creek Mesa Pit located in the same gavel terrace deposit as the proposed Haldorson Pit, and only 2/3 mile from Phase I, has mined to 30 to 35 feet below ground surface, and groundwater has never been encountered; • A test hole dug to approximately 60 feet at the Spring Creek site, during irrigation season, never encountered groundwater; • The Applehanz Base Products Pit, immediately east of the Spring Creek operation was excavated to a depth of 40 feet below ground surface and has never encountered groundwater; • The reclaimed topography at the site will not affect surface runoff at the site due to the minimal amount of precipitation at the site coupled with the aridity of the climate. The Supplemental Information for the Lewicki report submitted to the Division on February 27, 2004, includes the following additional pertinent information: • Additional wells drilled at the site indicate that gravel thickness in Phases I and R range from 57 to 64 feet, across the phase areas, supporting the likeliness that goundwater levels in these areas area relatively deep and not neaz the ground surface; • Current groundwater data for wells in the area show groundwater levels at 0 to 1 foot above the bottom of the wells; • Further study of the geology of the site revealed that a shale ridge exists to the south and west of the permit area trending in a southeasUnorthwest direction, therefore isolating the permit azea from other recharge areas of the mesa. This ridge appears to form an isolated area of 153 acres. Irrigation, precipitation, and groundwater outside ofthis isolated area appeazs not to drain into the groundwater at the site; • Percolation tests and sieve analyses of material at the site indicate rapid permeability and little resistance to water flow, therefore minimizing its ability to restrict groundwater flow and to cause groundwater levels to rise near the ground surface; • Letters from operators at neighboring operations confirm that groundwater is not encountered at these sites. Based on the new, additional information contained in the two Lewicki reports, it is the opinion of the Division that the condition included in the October 30, 2003 decision of the Board, related to the approved permit for the Haldorson Sand and Gravel Mine, merits reconsideration. The information contained in these reports appears to support the assumption that groundwater at the site is deep enough that mining to a depth of 13 feet prior to obtaining a whole year's worth of groundwater level data will not jeopazdize the groundwater at the site nor downgradient of the site. Additionally, the new information related to the apparent isolation of the groundwater at the site from the groundwater system of the remainder of the mesa further supports the view that impacts to groundwater in the area resulting from mining to 13 feet will be negligible or nonexistent. The operator currently has an approved monitoring plan that includes weekly monitoring of groundwater levels at the site, which will continue during the mining to 13 feet, if approved. Therefore the Division agrees with the proposal in the Lewicki fetter that the Board should reconsider its October 30, 2003 decision to prohibit mining at the Haldorson site until one year of groundwater level data from the site can be supplied to the Division for review. This reconsideration should consider allowing the operator to mine to a limited depth of 13 feet until the groundwater level data can be supplied and the groundwater conditions can be further analyzed. If the Board so desires, a condition to the approval of mining to 13 feet can include a trigger point at which mining operations will cease at the site if the weekly groundwater monitoring indicates groundwater levels have reached the trigger point elevation.