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as a replacement source for this plan. Lafarge will begin to make releases to offset these depletions in July 200 (Table No. 3). All releases will be coordinated by Scott Edgar. The water ++~ill be released on a monthly basis during the irrigation season. However, Mr. Edgar may utilize a block replacement ofwater for the accrued winter depletions (November to April) during the next water year. Again. Lafarge will use the existing accounting form developed for the resen oir to track storage and releases. DER'ATERING IDIPACTS The SEO is concerned with the lagged effect to the stream system from allowing a grounds+'ater lake to fill in completely after being dewatered during a mining operation. The SEO is most concerned with the situation when a mining operation dewaters directly into a stream during mining and then allows thepit to fill with groundwater, which creates an initial accretion to the stream with a lagged depletion at the end of mining. Fortunately, the Duckworth Pit will not be dewatered directly into Boulder Creek. As mentioned in the DMG mining plan application, the 12-acre eastern cell will be dewatered into ]daho Creek. The ~~°aterpumped into Idaho Creek will be diverted into the lake at the Lighthouse Cove Development which lies to the north of the Duckworth Pit. This lake is hydrologically connected to the alluvium. The dewatering water will be measured at the return point into ]daho Creek and at the diversion into the Lighthouse Cove Lake. The exposed surface area of Lighthouse Cove Lake will not be increased by these diversions. The diversion of de+eatering water into the Lighthouse Cove Lake is the recommended mitigation from the groundwater mode] developed to determine drawdown impacts from mining in support of the DI\4G application. The 2~-acre western mining cell will be dewatered into the Smith and Emmons Ditch. The Smith and Emmons Ditch does not direct]v return to Boulder Creek. but infiltrates into the allu+'imn in a field at the end ofthe ditch. These two discharge points for the dewatering water will not create the dramatic lagged effect on Boulder Creek when the Duckworth Pit is allowed to fill afer mining. No existing water rights on Boulder Creek near the Duckworth Pit +rill be injured when the pit is allowed to fill. No other water users will divert and consume the dewaterine water from this site. OPERATION OF PLAN This substitute water supply plan +eas developed under projected operations for the Duckworth Pit. The actual depletions from exposed water surface areas could vary from the numbers used for calculations in the formulation of this plan. Lafarge will utilize the "Monthh~ Accounting Fonn" found in Appendix C to calculate and report actual depictions incurred on a monthly basis at the Duckworth Pit. ~'1'ELL PER)\IIT APPLICATION .AND ~0'ELLS ~'1'ITHIN 6011 FEET A 600-foot well inspection for the Duckworth Pit was completed +vith `.','ater Commissioner Bob Carlson on 1\9arch 16, 200. A copy of his report and a list of well o+vners requiring notification++ill F'age 5