Laserfiche WebLink
Coal-Tar-Based Sealcoat Ban—City of Roseville <br /> Randy Neprash — Bonestroo & Minnesota Cities Stormwater Coalition <br /> May 23, 2011 <br /> Minnesota Cities Stormwater Coalition <br /> Bonestroo <br /> Municipal stormwater professionals <br /> workin g together ether for clean water <br /> Polycyclic Aromatic Hydrocarbons— PAHs <br /> • Group of chemical compounds that form whenever anything with a carbon base <br /> is burned <br /> o Examples - wood, gasoline, cigarettes, meat <br /> • Environmental concern <br /> o Seven PAHs are probable human carcinogens <br /> o Several are toxic, carcinogenic, mutagenic, and/or teratogenic (causing <br /> birth defects) to aquatic life <br /> Coal-tar-based sealcoating <br /> • PAH concentrations in coal-tar-based sealcoating are about 1,000 times higher <br /> than in asphalt-based sealcoating. <br /> Impacts to cities <br /> • We are finding high concentrations of PAHs in stormwater pond sediment <br /> o This makes disposing of the dredged sediment very expensive <br /> • Estimated cost— provided by the MPCA to Hennepin County <br /> o Based on an estimated 20,000 stormwater ponds in the Metro area <br /> Estimated%of total Estimated Volume Estimated Cost <br /> Cu/yards <br /> 50% 10,000,000 $5 Billion <br /> 25% 5,000,000 $2.5 Billion <br /> 10% 2,000,000 $1 Billion <br /> Why cities need to address this problem locally <br /> • The most effective method to reduce the future problem is to eliminate coal-tar- <br /> based sealcoating as a source of PAHs <br /> • The state and federal governments are not banning coal-tar-based sealcoating <br /> • The cities will bear most, if not all, of the coat to dispose of pond sediment <br />