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Regular City Council Meeting Monday, April 13, 2015 Page 20 from current assumptions as index levels reduce from 70 to 60 within the 2014 to 2034 timeframe. Mr. Culver advised that staff's recommendation, supported by the Public Works, Environment and Transportation Commission (PWETC) at their March 24, 2015 meeting, would be to suspend the current seal coat program, and shift the current allotted seal coat funds of$220,000 to the annual mill and overlay program to ac- celerate this corrective action, and starting in 2015. Mr. Culver noted that staff and the PWETC further recommended an annual review of that proposed suspen- sion to re-enact it if and when the issue seemed to be resolved. Mr. Culver admit- ted that staff remained unsure when the City would stop seeing the delamination distress; and clarified that typically staff remained a strong proponent of the ad- vantages of performing regular seal coat applications. Mr. Culver advised that it should be known within one to two years if the delamination was going to stop, but probably not before then. Mr. Culver noted that typically, the City got a long- er life from seal coating than for this current delamination issue. Councilmember McGehee asked if there were adequate records of the chemical composition of underlying pavement and sealcoat for each area of delamination on Roseville roads. Mr. Culver responded that those records were available through as builts for the roads regarding the mix used and type of seal coat oil used for Roseville as well as other communities experiencing the same problem. Mr. Culver advised that MnDOT had reviewed that data; however, he repeated the problem in attempting to duplicate the conditions in a lab setting to define what is causing the problem. Councilmember McGehee suggested staff and the PWETC examine the specific relationships on streets in Roseville to determine locally which mix was causing the issue in an effort to predict where the delamination may next occur versus guessing where best to do mill and overlays, basically the City's own research project. Mr. Culver advised that the problem was being observed on all City streets during the particular timeframe; and advised that mix designs since then have changed dramatically, allowing ongoing research and analysis on mix design and any de- lamination patterns affects. Before resuming sealcoating, Councilmember Willmus asked what information staff would look for that would satisfy them that the issue had been resolved. Mr. Culver advised that if pavements paved in a certain year were already found not to be demonstrating stress beyond years 16 and 17, and if the same experienc- es were found by consensus in other communities as comparisons were made with