APPCOR11847 - Laserfiche WebLink

Home Browse Search

Mr. Dave Canning Page Ten April 15, 1982 Shrub density (cont'd) But since there is only 1.6 acres of disturbed shrubland, no minimum shrub standard will be set. 2.05.6(6) Subsidence The applicant has amended the original permit application to correct deficiencies discussed in the Division's Preliminary Adequacy Review letter of April 20, 1981. The applicant has committed to the monitoring of the existing seasonally occupied ranch house structure within the potentially affected subsidence area. Further, the applicant has committed to the required monitoring and report frequencies. If damage should occur to the structure, the applicant is required under the performance standards of Rule 4.20.3(2) to "...restore, rehabilitate, or remove and replace each damaged structure, feature of value, promptly after damage is suffered...". One additional deficiency was detected during review. Unfortunately, this deficiency was not detected during earlier reviews of the Apex II permit application. Exhibit C, a map entitled "Five-year Mining Proposal", depicts underground mine workings within 50 feet of the northern and eastern permit boundaries in Block No. 3. If these underground workings were [o experience subsidence, manifesting the expected angle of draw of 250, surface disturbance might occur outside the permit boundary. Disturbance outside the permit area boundary is pre cluded by our regulations. The application should be amended to limit extraction within those areas adjoining the boundaries of the permit area, in order to preclude disturbance outside of 480 feet, a boundary pillar of approximately 225 feet in width would be required to preclude subsidence outside [he permit boundary. Extraction within that boundary pillar area should be limited to th 50% extraction limit being utilized beneath the structures and pond within Block 3. (See attached modified except of Map Exhibit C.} 2.05.5 Steep Slope Mining 1. The applicant has requested a variance from approximate original contour, based upon steep slope conditions. The original slope witfiin the portal bench area exceeded 80$. Further, a county road exists immediately below the bench. In view of these facts, the Division concurs that a variance from approximate original coutour is in order. However, in order to grant the variance, information relating to Rule 2.06.5 must be supplied. This Includes a change in [he post land use as described by the applicant from wildlife habitat to public land use for the area encompassing the County road right-of-way as per Section 2.04.3 of this letter.