Agenda - Public Works Committee - 01/17/2017

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Sunwood Drive—Street Improvements Ramsey,Minnesota NTI Project No.16.61770.100 GROUNDWATER ISSUES The following presents additional comment and soil specific issues related to measurement of groundwater conditions at your project site. Note that our groundwater measurements, or lack thereof, will vary depending on the time allowed for equilibrium to occur in the borings. Extended observation time was not available during the scope of the field exploration program and, therefore, groundwater measurements as noted on the borings logs may or may not accurately reflect actual conditions at your site. Seasonal and yearly fluctuations of the ground water level, if any, occur. Perched groundwater may be present within sand and silt lenses bedded within cohesive soil formations. Groundwater typically exists at depth within cohesive and cohesionless soils. We anticipate that a system of sump pits and pumps located outside of the excavation areas would be suitable for control if groundwater were to be encountered. However, a well point system would be more suitable for control of groundwater if excavations were to be advanced into the ground water table at depth in free draining granular soils. Additionally, we caution such seepage from such formations and any water entry from excavations below the groundwater table may be heavy and will vary based on seasonal and annual precipitation, and ground related impacts in the vicinity of the project. The groundwater surface should be maintained a minimum of 2 feet below the bottom of the excavation at all times.