PREFACE

A short history of mine drainage prediction and overburden analysis is appropriate. The Surface Mining Conservation and Reclamation Act of 1971 required that "(n)o approval shall be granted [for a permit] unless the plan provides for a practicable method of avoiding acid mine drainage…or other stream pollution." This requirement implied the obvious need for the development of techniques to predict mine water quality and an understanding of methods to prevent mine drainage pollution. As is often true, the law was ahead of the science; as is sometimes true, the law drove the science, in this case, to develop techniques that could fulfill the aims of mine drainage prediction and pollution prevention. New prediction tools were being developed, but interpretation of their results was in its infancy.

In the early 1970s, two laboratory methodologies- simulated weathering tests and acid-base accounting were being investigated. Pennsylvania’s Department of Environmental Protection (DEP) felt a need to explain to the mining community which overburden analysis methods were acceptable to the department and the requirements for submittal of data. This explanation took the form of a three-page letter to mine operators which accompanied permit application review letters from 1979 through 1981. As the science of mine drainage prediction developed, the department attempted to keep pace in its guidance documents. In 1980, the department developed an eight-page internal guidance memorandum to assist permit reviewers. A thirty-four page draft "Overburden Manual" followed in 1984. Concurrently, during the early 1980s, the Environmental Hearing Board upheld several permit denials based on the use of acid-base accounting. In 1989, in response to a much better understanding of the science, a revised draft manual was developed that was twice the length of the 1984 version. The revised manual included discussions of acid-base accounting and some other prediction techniques. The mining industry was concerned that acid base accounting was becoming the dominant decision-making tool for reviewing coal surface mine permit applications and that other techniques and pollution prevention measures were not being given more consideration. The Pennsylvania Coal Association (PCA) filed an action in Commonwealth Court, asserting, among other things, that the manual was either an invalid regulation or an improper policy. Settlement discussion ensued and a more cooperative atmosphere prevailed. It also became apparent, as time went by, that the 1989 manual was quickly becoming outdated because of progress in the science.

The settlement discussions provided both an impetus and a mechanism to begin what has turned out to be a lengthy revision. The 1989 volume had two authors, the present work has more than 20. A work with two parts has expanded to 18 chapters. The current work addresses industry concerns by the inclusion of numerous topics not discussed in the earlier work, such as discussions on geology and groundwater hydrology and simulated weathering tests. Other important additions are greatly expanded discussions of prediction methods other than acid-base accounting and a discussion of various pollution prevention techniques and the benefits of remining.

Throughout, both the DEP and the PCA, for similar and different reasons, saw for the need for an introduction which would clarify the purpose(s) of the manual which is no longer a manual. Certainly the book has more authors, covers more subjects, is longer and has a new title. More important, it has a new purpose, a new focus. It is now a technical reference document: the 1997 version of the latest scientific research and the most advanced scientific thinking about predicting mine drainage quality and preventing mine drainage pollution. It is not a regulation. It is not a policy. It should not be used as either. Inclusion of information or methodologies in the book does not guarantee applicability to a particular situation or assure permit issuance or denial. Absence of information or a methodology from the book does not mean that the information or methodology is inapplicable or that a site may or may not be mined.

Even a cursory review of the current version shows that scientific research and thinking have evolved greatly since 1977, since 1984, and since 1989. More importantly, our knowledge will continue to grow. This version of the book is meant to spur innovation, not to freeze thinking. New tests, practices, and ideas are sure to appear eventually, perhaps soon. The reader, whether in the department, in industry, or in the environmental community, should be vigilant for new material relevant to a particular site or situation which has developed after publication of this book.

One final caveat: Nothing in the book is a substitute for thoughtful and thorough decision making on each permit. Decision making should be based on site-specific information, application of any scientifically valid and appropriate methodology, and the exercise of common sense.

Martin A. Sokolow

Department of Environmental Protection

Harrisburg, PA 17105