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5. POLICY BOARD BUSINESS 5.01: Topsoil Standard and Results of Topsoil Study City Planner Anderson presented the staff report. He noted that the Board previously discussed the MnDOT specifications and made a recommendation at the December meeting. He noted that parks staff have been working on a topsoil study at North Commons and advised that the results are now available. Board Member Lewis arrived. City Planner Anderson stated that he would like a motion from the Board to reaffirm the recommendation made in December and advised that staff will continue to investigate conservation design techniques. Parks and Assistant Superintendent of Public Works Riverblood presented information on water usage and the percentage used for irrigation during the past couple years, as well as the positive effect that the topsoil has. He presented the results of the study that was completed which included sections of two inches and four inches of borrow soil and four inches and six inches of the spec'd topsoil and the water used in those areas for irrigation. He reported that the spec'd soil areas continued to use less water than the borrow soil areas and also noted that the areas of four inches of spec'd soil used less water than the areas of six inches of spec'd soil. Board Member Lewis questioned the cost to install the four inches of topsoil. Parks and Assistant Superintendent of Public Works Riverblood reported an estimated cost of $2,600 or $2,700 for four inches of topsoil for an average lot size. He advised that the average homeowner would see a decrease of approximately $74 per year in the irrigation costs and also reviewed the additional benefit to water treatment and the cost of new wells. He stated that without the requirement most people would buy black dirt. City Planner Anderson stated that at the time the topsoil requirements were created the intent was to limit the amount of sand in the soil material and increase the organic matter content, which is what helps with water conservation. Parks and Assistant Superintendent of Public Works Riverblood noted that there would be a cost savings to allowing the MnDOT specification, or an equal, until such time the City Council can revise the Code. He noted that the material would also be more readily available. Councilmember LeTourneau asked for Code information from neighboring communities. City Planner Anderson noted Blaine and Andover have more generic topsoil requirements that do not have a set standard that would make it difficult to compare their requirement to the soils used in the study. Councilmember LeTourneau questioned how long the current topsoil standards have been in place. Environmental Policy Board / May 5, 2014 Page 2 of 6