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Mr. Marlc G. Stodola Mr. Gary DeSantis Page 2 Apri12, 2001 Based on Mr. Stevens inspection, information provided in the variance request, and in accordance with Minnesota Rules, Chapter 4725, your request for a variance is granted to construct the subject well 86 feet from a safeguarded 4000-gallon underground petroleum storage tank and 35 feet from the ordinary high-water level o�Lake Minnetonka The variance is granted because there is no accessible location for a well on the subject property which satisfies all isolation distance requirements. The proposed well location appears to provide the greatest available separation between the well and known contamination sources both on and adjacent to the subject property. The presence of clay confining layers, and the additional grouting requirements, should provide additional isolation between su�cial contaminants and the aquifer. Because the isolation distances between the proposed well and the underground petroleum storage tank and the lake are less than required in rule, additional construction methods and precautions are required in order to reduce the potential for contamination of the well and groundwater. The following list of additional conditions and requirements should provide the necessary additional protection for the well and groundwater. The variance is granted with the following conditions: 1. The casing of the subject well must extend to a minimum depth of at least 100 feet. 2. The annular space between the casing and the bore hole wall must be filled with neat-cement grout or high-solids bentonite grout from a minimum depth of 100 feet and extend to the ground surface or base of the pitless unit or adapter. Neat-cement grout must meet the standards defined in Minnesota Rules, part 4725.0100. High-solids bentonite grout must be NSF approved and marketed as a well sealant. High-solids bentonite grout must be mixed to the manufacturer's specifications, or must meet the minimum requirements of 15 percent by weight bentonite as specified in Minnesota Rules, Chapter 4725, whichever is heavier. Grout must be inserted through the casing or through a tremie pipe. Any annular space below a depth of 100 feet in unconsolidated materials must be completely filled with cuttings taken from the borehole or with an approved grout. 3. The existing well, designated as Well Number 1,PWS 5270606, must be sealed in accordance with Minnesota Rules, Chapter 4725 within 30 days of completion of Minnesota Unique Well Number 655096. 4. You must contact Mr. Stevens at 651/643-2115, or Mr. Ron Thompson at 651/643-2108 at least 24 hours prior to beginning well construction, and at least 24 hours prior to beginning well sealing so that an inspector may be present during the well construction and sealing.