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An applicant must still provide the Division an adequate analysis of the hydrologic impacts to -1 surrounding property owners and well owners as part of DMG application process. In addition, 1 the SEO approved plans and designs shall be used to calculate an appropriate financial warranty, Where there is no SEO approved liner plan, the applicant will need to supply an interim reclamation plan. Such a plan will describe a reclamation plan for a site that does not include a fined pit. Once SEO approval is obtained for the liner design and construction, the applicant/operator may submit a permit modification to the application in order to change the reclamation plan. Based on the degree of difference between the interim reclamation plan and the reclamation plan for a lined pit, the Division will determine if the change is a Technical Revision or an Amendment to the application or permit. An Illustrative Example: Introduction An applicant proposes the installation of a slurry wall azound the pit area prior to commencement of mining. Design details and SEO approval letter are provided but no specifications or quality coatroJ/qualiry assurance plan is, included in the application. The applicant proposes to bond for the cost to install the slurry wall. Such a bond should serve as a contingency if leakage were to occur in e:tcess of criteria established by the Office of the State Engineer or if the slurry wall were to be damaged by pit slope failure. The unit cost supplied by the applicant in Exhibit L used to establish the amount of required bond is ($X) per squaze foot of starry wall assuming a wall depth of (17 feet. Lined reservoirs that employ slurry walls to prevent hydrologic communication with ground water are a viable water storage alternative and aze adequate to meet the developed water resources post mining land use. However, leakage of ground water through or around the slurry wall into the pit at a rate in excess of SEO requirements would constitute a failure to achieve the designated post mining land use. If an operator were to mine out a pit within the perimeter of a previously installed slurry wall, and it were subsequently determined that ground water was leaking into the pit at a rate in excess of SEO requirements, the operator would be faced with the following three options: Improve the seal in the pit to meet the State Engineer's leakage criteria. • Change the post mining land use and provide water to augment for ground water leaking into the pit that is lost to evaporation. • Backfill the pit so that water is no longer exposed to the atmosphere. In the event the Division were to assume responsibility for reclamation of the pit through bond forfeiture, we maybe confronted with the same situation and the same three options. Of these options, water augmentation in the river basin and back filling of the pit with inert fill would be the most costly. Also, neither of these options would result in reclamation to the developed water resources use. This leaves the option of assuring that leakage into the pit is less than SEO requirements through reinstallation or repair of the slurry wall.