Fractured tills, Ohio's ground water resources, and public policy considerations addressed by DRASTIC maps

Ohio Journal of Science, The, April, 2006 by Julie Weatherington-Rice, Ava Hottman, Earl Finbar Murphy, Ann D. Christy, Michael Angle

ABSTRACT. The public health of all Ohioans is dependent on land use decisions that preserve the quality of Ohio's water resources. If a potentially polluting site is located over fractured glacial tills, those fractures could hasten contaminant transport from surface contamination to underlying ground water. This paper addresses public policy, government programs, and the law as they affect land use decisions in fractured environments. A review of programs in Ohio identified a number of efforts currently in place that, if modified, could include ground water pollution potential mapping (DRASTIC) and the concept of fracture flow in guiding science-based land use decisions. Two of these programs, the Sole Source Aquifer designation and the Wellhead/Source Water Protection Program, are detailed. In addition, two Ohio law cases directly addressing ground water resource protection are described: Cline v. American Aggregates and CF/Water et al. v. Schregardus. The latter case is the first in the United States to explicitly state that fractures must be taken into consideration by the regulatory agency when reviewing a permit to install a potentially contaminating land use.

INTRODUCTION

Over 40 percent of Ohioans rely on ground water for their source of drinking water. Rural residents typically use their own private well at home for their regular daily water supply. In addition, many rural and non-rural Ohioans rely on the approximately 1350 community and non-community public ground water supplies in Ohio. The ability of those private wells and those public suppliers to provide safe, clean water is directly related to the quality of the raw water being collected for distribution, possible treatment, and the local supplier's ability to protect their resource (Smith 2004).

Thanks to the federal Safe Drinking Water Act and its various amendments, public water supplies have water quality standards that have to be met. For the rural Ohioan using a private water well, those water quality standards don't apply. Once the private house well has met a screening for total coliform bacteria and nitrates by the local health district, that well will often not be tested again until the home is sold to a new owner. The public health of Ohioans is subject to land-use decisions that have the potential to impact the quality of Ohio's water resources. For the most part, those land-use decisions are not made by scientists, but by people who trust that the local, state, and federal programs that they follow will keep their water resources safe.

Fractured glacial tills and the ability of those fractured settings to both recharge ground water and transport environmental pollution has been recognized by a small group of the scientific community since the 1880s (Read 1880; Brockman and Szabo 2000; Szabo 2006). However, moving that knowledge to the general population, to the decision makers and enforcement agencies charged with protecting Ohio's surface and ground water supplies has been a far more difficult undertaking. It is the loss of safe ground water resources due to contamination, at the local level, that has created the greatest level of hardships, sending local decision makers searching for protection strategies. For example, this pattern of wellfield contamination has been experienced along the Mad River-Great Miami River Buried Valley Aquifer from Urbana to Cincinnati during the last 30 years or more. Communities along that prolific ground water reserve continue to scramble to find new and/or replacement wellfields that are not already contaminated by historic land uses, including those located on the surrounding uplands covered by fractured glacial tills.

Regardless of these devastating local experiences, public policy and the law, for the most part, still function under the mistaken illusion that glacial tills and other fine-grained glacially derived materials are impermeable and, therefore, excellent locations for the construction of potentially contaminating land uses that may affect current and/or reserved public raw water supplies.

This misconception has been propagated, in part, by the time lag that exists between new discoveries in science and publication of those discoveries in nationally and/or internationally accepted textbook references. For example, the Domenico and Schwartz (1997) text Physical and Chemical Hydrogeology, as recently as 1997, considered glacial till to be impermeable, even though the research group from the Waterloo Institute for Groundwater Research at the University of Waterloo, Ontario, Canada had been writing about fractured glacial till in peer-reviewed hydrology journals since the mid 1970s. It wasn't until the publication of Ward and Trimble's Environmental Hydrology (2004), that the concept of permeable, fractured glacial till was incorporated into an internationally recognized English-language textbook and reference published in the United States.

If documentation of the concept of fractured till in standard hydrologic references takes almost 30 years to achieve, one cannot be surprised that regulations that people have to comply with and the laws governing those regulations, which always lag behind science, have not yet embraced a working understanding of the implications of fractured glacial till and other fine-grained materials as they relate to surface and ground water contamination.