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To help reduce these impacts on the WTP, Cotter proposes to undertake a grouting project <br />similar to that contemplated in 2012. For this project, the objective will be to reduce water <br />collected in the Sump 10 area as much is reasonably achievable; complete sealing of the <br />Sump 10 area is not expected. <br />TR -22 proposes that Cotter will utilize an experienced grouting contractor to install a grout <br />curtain with 19 initial holes (including re- boring the holes previously drilled in 2012) to be <br />drilled and grouted on a pattern that was previously developed in 2012. It is estimated that a <br />total of 38 holes may be drilled and grouted in total. <br />As noted above, the initial grouting pass will consist of 19 holes on approximately 10 -foot <br />centers. After a period of 2 -3 days, an inspection of the Sump 10 area will be made to <br />determine the effectiveness of the initial grouting and overall effectiveness of the project. <br />Based on these results, up to 19 additional core -holes may be drilled and grouted and, if <br />necessary, additional holes may be drilled to target zones with higher permeability. <br />For the project, the core -hole depths are expected to be about 35 feet totaling approximately <br />1,330 linear feet of drilling if all planned holes are required. The actual number of holes and <br />total drilling length may vary pending the response of the fractured strata to grout. While <br />Cotter does not expect any adverse effects on Monitor Well 18, Cotter notes that this monitor <br />well is installed in the same fractured strata, in the vicinity of Sump 10, where the proposed <br />grouting will take place. The significant distance between the area planned for grouting and <br />the monitor well (in excess of 110 lateral feet) coupled with the fact the monitor well is <br />completed to a depth of 235 feet, and screened only at the interval between 215 to 235 feet <br />below the surface, makes interaction between the grout and the monitor well unlikely as the <br />grouting core -holes will not extend more than approximately 35 feet below the surface. <br />Cotter will monitor the status of Monitor Well 18 for impact from the proposed grouting <br />program. <br />An underground injection control (UIC) permit is not required for this project. The <br />regulations indicate that UIC permits are required for certain classes of wells (5 types of <br />injection wells) and not for boreholes drilled for the purpose of sealing/grouting. A grout <br />hole does not meet the definition of an injection well. <br />For the proposed TR -22, Cotter will do the following: <br />1. Locate all underground utilities and other man -made obstructions, <br />2. Provide water for drilling, testing, and grout mixing, <br />3. Provide site access for drill rigs and storage area for materials and supplies, <br />4. Provide electrical power and sanitation facility, and <br />5. Provide a grouting plan for the primary grouting pass which shall include instructions <br />to grout each core -hole in three stages of approximately 10 -feet in depth. <br />The grouting contractor will do the following: <br />1. Provide all equipment, material and labor to perform the grouting, <br />2. Drill and grout core -holes according to the grouting plan, <br />3. Perform a water pressure test in each core -hole to evaluate permeability, <br />2 <br />