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Mr. Corey DeAngelis October 23, 2018 Page 2 Division of Water Resources'Reservoir Administration Guidelines as they apply to liners for subgrade storage." As you know, with regard to hard rock quarries, the Division of Water Resources (*'DWR") Reservoir Administration Guidelines state the following: "Rock quarries in low permeability material that seek to store water are tested in accordance with the Liner Guidelines discussed above as applied to lined excavations into high permeability material where the excavation intercepts ground water. They are also subject to the same two-tiered accounting approach discussed above. " Per the lining criteria referenced in the guidelinesZ, "A water balance must be done to demonstrate that the balance of the inflows (e.g., precipitation and ground water) and outflows (e.g., evaporation) equals the change in storage volume by a minimum of a 90-day test...The applicant shall demonstrate that during a 90-day test period the unregulated ground water inflow to the pit does not exceed the Performance Standard. Demonstration of inflows less than the Performance Standard shall be sufficient cause for a determination that the applicant has constructed a lined reservoir and is entitled to store water. " On April 2nd, 2018, we provided the former Division 1 Engineer, David Nettles, a letter summarizing our proposal for conducting the Spec Agg leakage test. The summary letter included information for the leakage test methodology and accounting, completion reporting and timeline for the test. This letter was assigned to Ioana Comaniciu, Water Resources Engineer for the Division of Water Resources, who visited the site on June 20th, 2018 while the leakage test was in progress to review the site and the proposed leakage test plan. Mr. Nettles and Ms. Comaniciu agreed with and approved the leakage test plan. Leakage Test Methodology and Accounting As is required by the DWR guidelines, the inflows, water level elevation, and outflows were recorded daily for the Spec Agg Pit throughout the 90-day test. Water level measurements were necessary due to existing water stored in the Pit under previous free river conditions. All known inflows into the pit were from surface inflows from Jackson Gulch and precipitation over the quarry pit area.To account for surface inflows from Jackson Gulch,a 12-inch ramp flume, stilling well, float and datalogger were installed at the bottom of the Spec Agg Pit,just above the reservoir area. The location of the flume can be seen in Figure 3. Additionally, inflows from precipitation were calculated daily based upon multiplying the precipitation recorded at the nearby NOAA Golden 3SW (USC00053387) weather station (location shown in Figure 3) by the water surface area in the bottom of the pit. Note that this does not include any precipitation in the quarry pit `cone' above the water line (frustum) that may result in inflows into the pit. ' DWR Reservoir Administration Guidelines(October 2011)at page 32. 2 State Engineer Guidelines for Lining Criteria for Gravel Pits(August 1999)at page 2. ®www.bbawater.comAssociates,