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B. Sedimentation Ponds <br />1. Alternative design criteria and specifications have been approved for use in <br />sediment pond design and/or construction. This decision is based on a thorough <br />analytical demonstration by a qualified professional engineer that the resulting <br />sediment pond will be as environmentally sound and structurally stable taking <br />into consideration physical, climatological, other chazacteristics of the site, and <br />will conform to the impoundment performance factor of safety of 1.3. <br />(4.05.6(11)). <br />C. Acid-forming and Toxic-forming Spoil <br />1. The Division proposes to approve temporary storage ofacid- and toxic-forming <br />spoil for more than 30 days. This decision is based on a finding that burial or <br />treatment of these materials within 30 days is not feasible and the delay will not <br />result in any material risk of water pollution or other environmental damage <br />(4.05.8(3)). See Section 2.04.6 for identification, mining plan contingencies, and <br />spoillmine soil reconstruction plans (respectively) that address acid or toxic spoil <br />horizons. <br />D. Ground and Surface Water Monitoring <br />1. The applicant will conduct monitoring of ground water in a manner approved by <br />the Division (4.05.13(1)). The ground water monitoring plan is as follows: <br />a. WFC maintains and operates a ground water monitoring network at the New <br />Horizon 2 mining azeas that currently consists of 12 monitor wells. Each <br />monitor well is measured for static water level on a monthly basis. <br />In order to obtain specific baseline water level information at New Horizon 2, <br />a total of 22 monitor wells were drilled and completed. In June of 1986, 16 <br />monitor wells (GW-N13, GW-N14, GW-N15, GW-N16, GW-N16P1, GW- <br />N17, GW-N17PI, GW-N18, GW-NI8P1, GW-N19, GW-N20, GW-N21, <br />GW-N22, GW-N23, GW-N24 and GW-N25) were installed. During August <br />and September of 1987, six additional monitoring wells were installed, (GW- <br />N29, GW-N30, GW-N31, GW-N32, GW-N33 and GW-N34). <br />Measurements for static water levels began at these wells immediately after <br />they were completed and developed. All of the water level data are presented <br />in tabular and graphic form in Appendix D of Attachment 2.04.7-1 <br />Hydrological Monitoring Plan. Five more wells (GW-N36, GW-N37, GW- <br />N38, GW-N39and GW-N40)were added in May 1993. The first three wells <br />were drilled in the north-east comer of the permit azea. The last two wells <br />were drilled along the Calamity Draw. <br />During November 1998, six (6) new ground water monitoring holes were <br />20 <br />