A new report from the Great Lakes Geologic Mapping Coalition presents a unique multijurisdictional, cooperative approach for producing 3-D geologic maps gleaned from 19 years of joint effort among eight state geological surveys, the United States Geological Survey and the Ontario Geological Survey. Richard C. Berg, the director of the Illinois State Geological Survey in the Prairie Research Institute at the University of Illinois, talked with News Bureau physical sciences editor Liz Ahlberg about the report, the coalition, and why 3-D mapping is important for managing water resources.
What is 3-D mapping? Why would you need to map an area this way?
Three-dimensional geologic maps are like a slice of cake, except the layers are made up of different layers of the subsurface containing different types of materials, and they are not always nicely organized. A map can show where groundwater might be available, and, importantly, where groundwater might be vulnerable to potential contamination. It may also show where limestone for aggregate resources would be readily available.
We are trying to prevent a tragedy from happening by knowing what is in the subsurface, so that land use can reflect the vulnerability of the aquifers. We want to prevent a recurrence of what happened in Walkerton, Ontario, where seven people died and nearly half of the population of 5,000 fell ill from drinking water contaminated with Escherichia coli. Accurate mapping is like health care for the land.
What has the coalition accomplished?
When the coalition began in 1997, less than 10 percent of the subsurface in the Great Lakes region had been mapped. To date, we have conducted detailed surficial and 3-D geologic mapping within all the members’ states and Ontario, and we have made significant advances in understanding the glacial history and geologic processes of the Great Lakes region, training early-career scientists in new mapping techniques and emerging technologies, and sharing those technologies with our coalition partners.
We also have made remarkable advances in portraying this information in 3-D and conveying to municipal, state and federal officials the importance of applying this information for land and water use, all of which supports economic development. We have developed a system for providing public policymakers with scientific information in understandable formats.
Most important, we have developed a successful model for long-term multiagency collaboration in geologic mapping to address common issues related to the public good.
Can you give any examples of how your maps have helped officials make decisions?
3-D geologic mapping in Winnebago County was used to help county health officials identify “hot spots,” or areas where they suspected that groundwater was contaminated by industrial pollutants. By overlaying land-use maps on aquifer-vulnerability maps, and then performing targeted well-water sampling, the county discovered contaminated groundwater in multiple locations, and residents were taken off their local well water.
After that, statewide 3-D mapping was immediately incorporated into the Illinois Administrative Code defining aquifers. Growing out of this was Illinois’ Plan for Protecting Groundwater, the Illinois Groundwater Protection Act and Section 13.1 of the Environmental Protection Act. The latter established a groundwater monitoring network and the identification of critical groundwater areas. The mapping is also the basis of Illinois’ statutory definition of potable resource groundwater as defined in the state’s Joint Committee on Administrative Rules Administrative Code, Title 35.
What has 3-D mapping accomplished in the Chicago area, which you outline in the report?
We have recently completed very detailed 3-D mapping in Lake and McHenry counties, focusing on delineating multiple aquifers in the upper 200 feet. Our current work in Will County illustrates how we have cooperated closely with state and federal officials. We’ve talked with every county agency and state and federal representative in the county to explain what the coalition is doing and why we are doing it. We provide them with an update of what we’ve done during the previous three months and what we are planning to do in the next three months, and we receive their input on the county’s natural resource and environmental priorities to make sure that the products we design for them – like the maps of aquifers and available limestone aggregate mentioned earlier – suit their needs.
What could other regions or disciplines learn from this report?
Other coalitions like this could form, such as on the Atlantic Coast and in the desert states. It is a model that could be applied to other aspects of science as well. Rather than competing for funding, scientists cooperate to improve everyone’s prospects of being funded and then pool resources to solve perplexing issues. We have found a formula for long-term collaboration that works.