William W. Shilts, Chief
Illinois State Geological Survey


The environmental impacts of energy use in Illinois can be broken down into those that result from production of energy in the state and those that result from consumption of energy. Our primary sources of electrical energy are coal, nuclear, and gas. Petroleum products are both imported and, to a much lesser extent, produced here and are used primarily for transportation and heating.


COAL: Coal has traditionally been our primary in-state source of electrical energy. There are five major environmental issues related to the production of coal:: 1) Siting of coal mines with respect to population distribution. Increasingly, with the advent of economic pressures that drive the creation of mine mouth electricity generation, siting is an issue. 2) Quality of coal itself is a major environmental issue in Illinois and research into the concentrations of deleterious components, in which we already are engaged, will have an effect on coal production in the state. 3) The disposal of waste rock from mining, past and future, is an ongoing research problem that must continue to be addressed, particularly if coal extraction increases in Illinois, as I think is likely. 4) Subsidence over mined out areas is an ongoing hazard in areas where coal was or will be extracted in the subsurface. Present research on this problem consists of mapping mined out areas using historical documents and, recently, using reflection geophysics to map in the subsurface. The combination of "real time" geophysical surveys, historical documentation, and new methods of mining and documenting mined-out areas hold the promise of resolving this traditional problem. 5) Water contamination related to mining below the water table is an ongoing environmental issue that should be addressed more easily in Illinois than any other state because of the large number of water researchers in state and federal institutions, as well as in the private sector.

OIL: Illinois has had and still has an active oil industry. Research at the Geological Survey and by private explorationists suggests that considerable reserves remain, though only a small percent of our in-state needs will ever be satisfied by Illinois production. Environmental issues that are and will continue to be associated with oil production are protection of our aquifers and disposal of formation waters and trace metal-rich sludge that accumulates in the numerous oil storage tanks into which our crude oil is pumped.

GAS: Although Illinois has virtually no native gas production capability at present, we are beginning to investigate the possibility of producing methane from our extensive buried coal beds. This has become a major source of natural gas in the coal fields of Wyoming and elsewhere, and we are presently attracting state funds to evaluate the economic feasibility of developing a similar energy source here. Environmental problems associated with the production of coal-bed methane are not so clear as those for our other native energy sources, but, as you will see below, there may be substantial environmental benefits associated with its production.


COAL: About 45 percent of our electricity is generated by coal in Illinois, though an increasingly large percentage of coal burned is the less expensive, low BTU, low-sulfur coal that we import from Wyoming and other western states. The environmental issues associated with the burning of coal to produce electricity are well known-they include emissions of sulfur (SOx) and nitrogen (NOx) compounds to create excessively acid precipitation, emissions of large amounts of CO2 that provide an anthropogenic component to global climate change, and burning coal, from whatever source, creates substantial amounts of waste ash. Finally, coal-fired electricity generation requires high consumption of water and produces thermally altered waste water in the processes of steam generation and cooling. Funded by the state and by the federal government, research on several of these environmental issues is and will continue to be pursued in Illinois. We have been investigating the possibilities of producing inexpensive activated carbon, or char, from various types of organic compounds. One of the most promising of these is the solid corn residue left over from the production of ethanol. Chars made form various waste products are being tested to determine their efficiency in removing metals, such as mercury, from emissions. The CO2 problem is being approached by seeking state and federal funds to investigate two ways of improving our emissions balance. The first is the design of a system in which coal is burned in a pure oxygen atmosphere, which not only eliminates nitrogen emissions that result from combustion in normal, nitrogen-rich air, but produces a more pure CO2 emission that requires far less volume for storage. The second research initiative involves investigating the sequestering efficiency of deep bedrock reservoirs into which carbon dioxide can be injected and sequestered permanently. We are also looking at the possibility of injecting CO2 into coal beds to drive off coal bed methane, which would be captured as a fuel source. Carbon dioxide could also be injected into older oil fields that are not capable of producing flow under natural conditions. Since the chemical reactivity of the CO2 would allow operators to recover oil that is presently not recoverable, environmental mitigation could have an economic payoff, making the mitigation cost neutral or negligible. The ash byproducts from burning coal, whether it is of Illinois origin or from the west, have been the focus of a long-term research program that aims to find commercial uses for products made from the ash, such as construction bricks. Finally, we are studying new flotation methods to remove sulfur and utilize the substantial amounts of fine-grained coal waste that is presently wasted and disposed of where coal is mined.

GAS: Illinois is one of the nation's major gas consumers, and we serve as a distribution conduit for many neighboring states. To prepare for the cyclic seasonal use of gas, we have developed gas storage reservoirs in fractured or porous bedrock. The appearance of "gas peaker" plants in Illinois is going to require more storage capacity and probably more gas pipelines to supply the thermal energy they require to produce electricity. The pipelines, the storage reservoirs, and the peaker plants, themselves all have to be sited with a full understanding of the geology and hydrology of nearby and contiguous aquifers and geological substrates. Combined-cycle peaker plants, in particular, require substantial amounts of cooling water, and the impacts of withdrawals are difficult to predict without an idea of the local geology and hydrology. Our 3-dimensional mapping program focuses on aquifers and with accompanying hydrogeological studies is designed to provide background information of critical importance in evaluating the impacts of gas consumption and storage. Another impact of gas storage in natural reservoirs is the potential for leakage through unmapped fractures. Research into preventing these leaks through proper geological siting should be increased as should research on the technologies required to detect them.

NUCLEAR: Nuclear plants constitute a major proportion of our electricity output in Illinois. Though the high level waste from these facilities is not likely to be an environmental concern here because of our lack of suitable geological conditions for storage, our low-level waste has been and probably will be an environmental issue again at some point. We have already spent close to 100 million dollars on unsuccessful attempts to find storage sites, and although we don't have an active program for siting such waste at the present, we must be prepared to search for one in the future, whether we eschew the nuclear option or not. Any potential search will be enhanced by the 3-D mapping and aquifer study programs now going on and by Illinois' advanced capabilities in GIS. GIS techniques provide effective screening tools for siting low-level storage sites.


Illinois does not use energy in isolation from the rest of the nation nor from the rest of the world. The events of September have brought that home to us and will probably forever alter the way we look at the dependence on foreign energy sources. There are strong pleas both at this conference and nationally to adopt energy conservation measures, and I am sure this will be a major goal of our governments. Nevertheless, we will still have to have substantial conventional sources of energy, particularly to generate electricity, for the foreseeable future. This means that some energy sources that currently are out of favor with the public will receive scrutiny to see how they can be tapped while preserving the environmental standards we have worked so hard to develop. In Illinois, this means coal, and to a lesser extent nuclear, coal bed methane, and oil. Nationally, ethanol, too, may dramatically increase in use, if just as an oxygenate. The substantial amount of CO2 that is a byproduct of ethanol production, though of commercial value on its own, may increase to the level where it will have to be sequestered, as may CO2 generated by coal and gas burning.

National and international forces that will influence our access to the abundant energy supplies we enjoy now are already causing us to reexamine our energy and environmental priorities. Decisions we make in Illinois about our energy mix will have repercussions on our North American neighbors. For example, the wrangle over the advisability of drilling for more oil in the Arctic National Wildlife Reserve is generating major debates in Congress. Our energy decisions will also affect our relationship with Canada, from whom we already import considerable amounts of natural gas, because of Canada's huge, unconventional reserves of petroleum in the Alberta tar sands and her substantial oil and gas fields on the environmentally sensitive east coast and in the even more ecologically fragile high Arctic. American companies are already acquiring major Canadian energy companies in anticipation of major shifts in the politics of energy. As the fifth most populous state and one of the world's major economies, where we buy our oil, gas, nuclear fuel, and coal will have tremendous impacts on our national and international neighbors, not the least of which will be the environmental legacy that will be left by the extraction of the energy resources we need.


Finally, a few words about coal. Coal is Illinois' great, largely untapped energy resource. Of the 38 billion recoverable tons of the 200 billion tons of coal that underlie Illinois, we actually mine about 40 million tons per year. Even doubling that amount to be more self sufficient would provide us with most of our electrical energy needs at present rates of consumption for the next 425 years. This is an energy temptation, especially in an uncertain, energy-thirsty world. In the absence of an alternative energy breakthrough, coal will hold the attention of Illinois politicians and citizens for years to come. The environmental risks of burning coal are substantial, but various research centers in Illinois and elsewhere are working hard on technologies that can make coal-generated electricity cheap and environmentally benign. It is the role of the state and its nation-leading scientific and technological research facilities to be a part of this research effort and to be proactive in providing the government with the information it needs to make the decisions that best balance the environment/energy equation for Illinois and the continent.

Presented at the 2001 Governor's Conference on Energy and the
Illinois Environment, Springfield, Illinois, November 8, 2001