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EFCI contracted with Bishop -Brogden Associates, Inc. in an attempt to model the refilling of the mine <br />cavity. The modeling approach was to estimate the rate of mine inflow, approximate some other <br />parameters, and propose alternative scenarios regarding the integrity of seals within the workings. The <br />output was an estimate of the time it would take the mine to refill to the point at which MWNW was <br />blocked. Although a detailed critique of the model is not appropriate here, it is important to point out <br />that the model cannot presently be validated. <br />History of NOV CV -2013-002 <br />Upon discovering that MW -NW was blocked, the Division issued NOV CV -2013-002 on January 28, <br />2013. The reason for the original NOV was for a "failure to ensure that water monitoring well MW - <br />NW continues to function as designed." There were two abatement steps in the original NOV: <br />Remove the obstruction from MW -NW or establish a replacement water monitoring well <br />that intercepts the Southfield Mine workings in the Red Arrow or Jack O' Lantern Coal <br />seam; <br />2. Provide evidence to the Division that Energy Fuels Coal Inc. has applied for a monitoring <br />well permit with CDWR in accordance with Rule 2.03.10. <br />After further technical review and consultation with EFCI, the Division modified the NOV on March <br />25, 2014 to amend the first abatement step as follows: <br />1. Remove the obstruction from MW -NW, or establish a replacement water monitoring well <br />that intercepts the Southfield Mine workings in the Red Arrow or Jack O' Lantern Coal <br />seam, or provide information confirming that the n,ell is currently functional, for the <br />intended purpose. " <br />The second abatement step, proof of application with CDWR, was completed on May 23, 2014. <br />With respect to the first abatement step, EFCI was not able to remove the obstruction, as it is likely <br />caused by a crushed well casing. EFCI determined that removal of the obstruction was not a viable <br />option. Neither was EFCI able to demonstrate to the Division's satisfaction that the well was <br />functional for the intended purpose. Therefore, the only means by which the first abatement step could <br />have been completed was to replace the well. With this intention, EFCI submitted technical revision <br />46 (TR -46) proposing a replacement well, MWNW-2, to be drilled into the mine workings. <br />During the adequacy review of TR -46 the Division and EFCI engaged in multiple meetings and EFCI <br />submitted relevant technical and economic information related to drilling a new monitoring well. <br />Two relevant documents submitted by EFCI which assisted in the Division's deliberative process are <br />Risk and Economic Evaluation to Redrill or Relocate MW -NW, and Response to Initial Adequacy <br />Review - July 9. In addition to information provided by EFCI, the Division utilized its own internal <br />expertise when conducting the technical review related to water quality/quantity. In particular, in <br />June 2013 Division staff drafted a comprehensive memorandum related to the Southfield mine and <br />related water quality/quantity matters. <br />During the technical review of TR -46, the Division weighed the benefit/value of the information <br />gained from establishing a new monitoring well against the considerable safety, health, environmental <br />risk, and expense of re -drilling a new well. Ultimately, as explained below, the Division is of the <br />