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Ms. Angela Bellantoni June 9,2014 Page 4 To the extent that the proposed locations are altered as a result of road construction, property ownership or other mining activities, we suggest that nearby monitoring locations are selected that will effectively intercept the same ground and surface water flow as the proposed locations. Guidelines for Installation of Ground Water Monitoring Point Each ground water monitoring point should be constructed as a monitoring well consistent with the State of Colorado's Water Well Construction Rules (2CCR 402-2)2. The casing diameter of the well should accommodate the collection of water quality samples either with bailing methods or with a submersible pump. As a guideline, if the water level is deeper than 40 feet, we suggest completing the well with a minimum 4-inch inside diameter casing to accommodate the installation of a submersible pump to be used specifically for monitoring purposes. Because of this casing diameter requirement, we suggest drilling and completing the well using air percussion or air rotary methods. Due to the unknown subsurface conditions, it is not possible to specify constructed monitoring well depths. We suggest completing the well in only the shallowest ground water producing zone. Because the wells will be located in topographical drainages, ground water will likely be encountered at shallow depths, but given the hard rock nature of the bedrock, it is possible that well yields may be low, and minimal ground water production may be noticed during the drilling process. If the shallowest ground water zone is encountered at depths shallower than 20 feet, then it may be necessary to obtain a variance from the State Engineer's Office for the construction of the well with a grout seal to a depth of less than 20 feet. Approved monitoring well permits should be obtained for the wells. If needed, the wells can be constructed under Notices of Intent to Construct Monitoring Wells3 submitted to the State Engineer's Office which can be later converted to monitoring well permits using the State's Monitoring / Observation Well Permit Application4. Guidelines for Installation of Surface Monitoring Points We suggest that for surface water monitoring points, a simple diversion of the surface flow is constructed in the drainage on either a temporary or permanent basis using a short section of clean pipe. The purpose of the diversion pipe is to collect and channelize any surface flow, which may occur in very limited quantities, into a discharge point at which a water quality sample can be collected without submerging the sample containers. Channelizing the flow may be a necessity in low flow conditions. Depending on site conditions and to offer a guideline, a three inch PVC pipe of six of more feet in length may be adequate for this purpose. Other than channeling the surface flow into a pipe, we do not believe that any additional construction or changes are needed to implement the surface water diversion point. Guidelines for Operation of Surface and Ground Water Monitoring Points The monitoring program should include observations of both quantity and quality, as summarized below. Ground water monitoring points—water quantity In order to determine changes in water quality, it is important to identify changes in water quantity (water level)that may impact water quality. We recommend visiting the locations to measure and record depth to water in the wells using a clean electronic water level indicator. Alternatively, a water level transducer and data logger can be installed in each well. We suggest monthly water level measurements. z htw://water.state.co.us/D'%TdPub/Documents/constructionruiesO5.pdf 'L*P://water.state.co.us/DWR1 Pub/Docutnents/aws-5 1.pdf 4 hip:Hwater.state.co.us/D"lPub[Documents-/vws-46.pd