Agenda - Council - 07/09/2002 - Laserfiche WebLink

Home

-4- P.W. CASE # INFORMATIONAL PRESENTATION OF WELLHEAD PROTECTION REQUIREMENTS FOR CITY WELLS By: Steven Jankowski, City Engineer Background: Wellhead Protection is a Program intended to prevent human-caused contaminants from entering wells used by public water supply systems. Replacing contaminated wells is costly, as is constructing treatment facilities to remove harmful contaminants. The Minnesota Department of Health was granted authority by the Minnesota Groundwater Protection Act (Minnesota Statute 1031 Section 3 Subpart 5) to prepare rules specifying Wellhead Protection measures for public water supply wells. The purpose of this case is to provide Council with a brief overview of the Wellhead Protection Program as it relates to the City of Ramsey's system. In 1997, the Cities of Ramsey, Anoka, Blaine, Centerville, Circle Pines, Coon Rapids, Fridley, Lexington, Lino Lakes, Spring Lake Park and Anoka County entered into a Joint Powers Agreement to form the Anoka County Municipals Wellhead Planning Group. Wellhead planning requires detailed groundwater modeling to determine ground water movement and well recharge access. Since Cities in the Anoka sand plain share a common geology, it was felt that money could be saved by hiring one entity to prepare the ground water modeling. Subsequently, the Department of Health received funds for it to underwrite the cost of this modeling and plan development. The work performed to date has been at no cost to the City other than staff time. At this point the groundwater modeling and preliminary inventories have been completed. Three important determinations have been made. Inner Wellhead Management Zone This is a distance of up to 200 feet around each well. This area is inventoried for 59 conditions or potential hazards. A listing of these condition and hazards is attached to this case. All four of the City wells are in compliance with all of these conditions. In the future, the City will be required to maintain these separations for new potential contaminant sources. Additional recommendations are that a six-foot chain link fence to secure a fifty-foot area around the well from vehicle hauling contaminants. Well Vulnerability Wells are classified as either being vulnerable or not vulnerable. Classifications are based upon a number of factors including well construction and condition, water quality history, and the sensitivity of the geology to contamination. The results of the vulnerability assessment for Ramsey's wells are that wells 1 and 2 are not vulnerable, while wells 3, 4, and 5 are vulnerable. The reason for vulnerability stems from the