Naturally occurring arsenic can make groundwater unsafe for drinking. Before going to the expense of drilling a well and sampling the water for arsenic, it would benefit public health to be able to predict the level of arsenic in groundwater in a certain area. A special research project with the U.S. Geological Survey is designed to develop the capacity to assess local geological conditions, related groundwater chemistry and well construction factors in three counties in order to predict the levels of arsenic found in groundwater related to those variables.
The County Well Index (CWI) contains well and boring records wells within Minnesota; over 400,000 records. It is the principal source of well construction information and geologic interpretations of well records and also contains soil boring records, mineral exploration test hole records, and scientific/research test hole records.
The Drinking Water Contaminants of Emerging Concern (CEC) program identifies environmental contaminants for which current health-based standards currently do not exist or need to be updated, investigate the potential for human exposure to these chemicals, and develop guidance values for drinking water. Contaminants evaluated by CEC staff include contaminants that have been released or detected in Minnesota waters (surface water and groundwater) or that have the potential to migrate to or be detected in Minnesota waters.
Appropriations from the Clean Water Fund allow the Minnesota Department of Health to expand and improve the way groundwater and drinking water protection is implemented at the local level. In 2015, $300,000 was allocated to update wellhead protection areas within groundwater management areas. From 2016 onward, funding will be dedicated to the Groundwater Restoration and Protection Strategies (GRAPS) initiative which will provide groundwater and drinking water information and management strategies on a HUC 8 watershed scale.
The objective of this project is to build on previous efforts aimed at determining the public health risk due to virus contamination in Minnesota groundwater. The Minnesota Department of Health will examine the occurrence of viruses in non-disinfecting groundwater sources in Minnesota as well as evaluate the association between source water virus occurrence and community acute gastrointestinal illness.
Arsenic occurs naturally in soil and minerals and is commonly found in groundwater throughout much of Minnesota. The occurrence and distribution of arsenic in groundwater is difficult to predict. Research is steadily increasing our understanding of the mechanisms and geologic conditions that determine arsenic occurrence in groundwater. The arsenic concentration in a new well, measured at the time of construction, is sometimes higher or lower, compared to subsequent sampling results.
Approximately 70 percent of all Minnesotans rely on groundwater as their primary source of drinking water. Wells used for drinking water must be properly sealed when removed from service to protect both public health and Minnesota’s invaluable groundwater resources. The Minnesota Department of Health protects both public health and groundwater by assuring the proper sealing of unused wells.
Clean Water funds are being provided to well owners as a 50% cost-share assistance for sealing unused public water-supply wells.
Educate well owners on the proper operation and maintenance of their wells, prepare and send letter to owners of properties in moderate and high vulnerability portions of the DWSMA and educate property owners in the DWSMA on issues related to source water