Agenda - Council - 09/25/2007 - Laserfiche WebLink

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MnlDOT Agreement No. 91083 Anoka County Project Number SP 199-010-09 Exhibit A, Scope of Wark and Deliverables The consultant will perform background noise level monitoring for four (4) sites during the daytime along TH 10. This monitoring will be performed in accordance with MPCA requirement and standards. The consultant will work with Mn/DOT Metro Division Noise Office in determining the locations of the monitoring~ The consultan~ will use Mn/DOT's nois~ model, MINNOISE. Peak hour traffic volumes for, both daytime and nighttime for the build and "No Build" conditions will be used. It is anticipated thatnot more than 10 modeling receptor sites will be needed for the entire project corridor. The consultant will show (in the EA and on the final layouts) the noise walls that meet the MPCA and/or FHW A requirements for noise wall installation and are cost effective. For noise barriers to be constructed, the cost will not exceed $3,250 per dBA of reduction per residence. For barriers to be , warranted, they must be effective by providing a meaningful reciuction in noise. State employs a guideline of 5 dBAThat is, unless the proposed wall can result in a reduction of at least 5dBA at the receptor, it is not pursued. The consultant will prepare the "No Build" and fmallayout build Air Quality Analysis for TH 10 (one hour average and eight hour average) for one and 10 years after construction (2010 and 2020) using the' Mobile 6.2 Emissions Model (dr most current emissions model) and the CAL3QHC dispersion model. It is assumed that one intersection and one free flow analysis will be required for each intersection/interchange. The consultant will perform a qualitative mobile source air toxin analysis. A preliminary drainage analysis will be conducted for the TH 10 corridor. Evaluation will include, but not be limited to location 'and size of principal culverts and storm sewers, water quality consideration, ponding locations, flood plain impacts, and wetland delineation. The wetland delineation will include estimated impacts to the wetlands for the various roadway design options and identification of the potential mitigation sites. The drainage analysis will be coordinated with federal, state and local agencies having either jurisdictional or review authority over the final drainage design and will be closely coordinated with the Mn/DOT Water Resources Engineering Office. Field visits with those agencies will also be conducted. Flow direction, high point and low point locations, pond locations including which areas are treated by each pond, wetland delineation and mitigation locations, flood plain impacts, and downstream water bodies receiving runoff from these roadways will be shown in the EA in relation to the final proposed roadway alignments~ Drainage area maps with pertinent data such as boundaries of the drainage area, runoff coefficients, time of concentration, and land use projections will be prepared. All proposed future drainage systems (culverts, ponds, and downstream tailwaters) will be designed using the corridor city's comprehensive zoning plans and aSsume 100 percent developed conditions. ' The consultant will produce a hydrologic model for existing and proposed conditions for the 24-hour duration, Soil Conservation Services Type II' rainfall event storms of 100 year or other recurrence intervals as required by permitting agencies. A plot and output file of the hydraulic grade lines in reference to the roadway profile will be produced for the storm events analyzed. The drainage system will be analyzed for the lO-year storm for normal pavement drainage and the 50-year storm for low points; the 100-year tailwater will be considered when analyzing the pavement and roadway low point drainage. Software packages including HydroCAD and XP-SWMM will be used. The NPDES Phase II -389- Page 2 of7