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Northfield Partners, LLC Northfield Exploration Project BASELINE HYDROLOGY MONITORING PLAN -SUPPLEMENTAL INFORMATION "Spring Creek" is an ephemeral stream with a small drainage basin. Within the leased area, the stream lies in a narrow canyon with prominent sandstone cliffs. Its stream channel is narrow with apparently shallow alluvial/colluvial surface materials. Field observations of the channel revealed azeas of minor erosion and scoured sediments, indicating that surface water flows have occurred in recent yeazs. Stream flows will only occur in response to snowmelt or significant rainstorm events. This statement is supported by the observations of a long-term landowner living by the stream neaz the north boundary of the leased azea. He stated that streamflow has seldom occurred, and that observed flows happened after heavy, local thunderstorm events. The same landowner indicated that a small spring was present in stream channel in the vicinity of leased area northern property boundary, and that it flowed for most of the yeaz. Subsequent field observations determined that there was surface water flow in the stream bottom of less than one gallon per minute. The origin of the flow, based on vegetation characteristics, was located within the leased azea, approximately 400 feet south of the north property line. Northfield sampled the flow from the spring/seeps on May 31, 2005, and will continue periodic sampling when flows aze present. "Plum Creek" is an ephemeral stream with a small drainage basin. Within the leased azea, the creek has a moderate gradient through a small canyon with sandstone bluffs. The stream channel appeared similaz to that of Spring Creek described above, indicating that flows occur only in response to snowmelt or heavy rainfall storm events. Northfield learned that stream flows have also occurred in past yeazs as a result of dischazge from the abandoned Chandler Mine air shaft located neaz the center of Section 15. Northfield investigated the Chandler Mine air shaft accompanied by a representative of the landowner, the Cotter Corporation (Cotter). Cotter maintains the sealed air shaft and the associated water catchment pond that receives dischazges from the shaft. The small pond measuring approximately 150 feet in diameter and containing water, lies in the channel of Plum Creek approximately 300 feet from the shaft site. No dischazges have been observed at the shaft during the last three yeazs, and Cotter sampled dischazges that occurred prior to that time. These observations suggest two characteristics regazding future surface flows in Plum Creek: flows may occur only as a result of dischazge from the Chandler Mine air shaft; and surface flows from a storm event will pass through and be affected by the catchment pond prior to reaching the leased area. Both Spring Creek and Plum Creek aze minor ephemeral streams that produce occasional surface flows in response to significant storm events. Northfield does not propose to monitor surface flows in either drainage for the purpose of obtaining baseline hydrologic data. In the case of Plum Creek, surface flows quality data would be significantly altered by the mixing of runoff and pond 2 - 06/30/05