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Ground Water Control Plan - For modification to NOI %-96-219-01, Cottonwood Land Company Groundwater aquifers will be penetrated during drilling. The significant bedrock aquifers of the area are contained within the Upper Williams Fork Formation, the Twentymile Sandstone, and the Trout Creek Sandstone. These aquifers are known to be continuous across the project area, and often yield artesian flows. Other minor local aquifers do occur and consist of thinly interbedded, very fine grained sandstones, siltstones, and coal beds. These minor aquifers are generally laterally discontinuous and have low and variable water yields. In the event that artesian flow is encountered during the drilling activities the following control measures will be implemented to maintain waters within the confines of the drilling pad: 1) water from the hole will be routed to excavated mud pits located on the drilling pad, 2) If the flows can not be easily handled via the use of mud pits, sealing of the sidewall will be attempted by using a low-sodium bentonite mud, 3) excess water which contains high proportions of solids will be transported by a vac-truck to a permitted disposal site, 4) each hole will contain steel surface casing that will be cemented in place, prior to beginning the hole. This practice will allow for the drill hole to be shut off at any time. During drilling, geophysical logging, or water monitor well completion, it is possible that water discharge off site may be necessary for limited periods of time. In the event that this discharge is necessary, the discharge will be channeled through additional settling pits, straw bales or other suitable material in order to remove suspended solids in an effective and practical manner. As necessary to control erosion in areas between the drill pad and nearby natural channels, either a ditch lined with gravel and/or geotech fabric, or water hose will be installed to the point where the gradient is low enough to prevent erosion. Records of discharge volumes and water quality field parameters (temperature, conductivity, and ph) will be maintained during discharge events, in accordance with guidance recently received from Colorado Division of Water Resources (CDWR) and Colorado Division of Public Health and Environment (CDPHE).