Limestone ordinances of New Jersey and Pennsylvania: a practitionerʹs experiences

Ordinances promulgating land use procedures related to construction in areas underlain by carbonate rocks have been under discussion since the mid-1970s in Pennsylvania and since the mid-1980s in New Jersey. At first, the proposed ordinances only considered ground water contamination then, later included the safety- (or stability) related concerns of constructing in karst areas. The first ordinance addressing both concerns as well as not being so restrictive as to eliminate development is believed to have been passed in Clinton Township, New Jersey in May, 1988. ly, several other nearby townships have passed ordinances based (either loosely or tightly) upon the “Model Ordinance” developed by the “Limestone Committee” of the North Jersey Resource Conservation and Development Council. The Model Ordinance has its roots in the Clinton Township Ordinance. Other ordinances, with little to no geotechnical input, have also been passed (and sometimes repealed) by well-meaning municipalities. As the subsurface conditions are complex and erratic (folded and faulted carbonates), an appropriate site evaluation is difficult to define and generally more costly to perform than a conventional site investigation. With this mix of ordinances, the variability in subsurface conditions and the diverse experience levels of the regional practitioners, the resulting effectiveness of these ordinances is mixed, from the humorous to the very positive. In general, the Clinton Township and Model Ordinance-based legislation, which specify procedures to be used in an investigation, work well. Other ordinances refer to standards which do not exist, have requirements which cannot be met in the real world, or appear poorly related to any realistic geotechnical concepts. aper will describe some typical examples of projects from the viewpoint of both the reviewer and the submitter. A state-of-the-practice presentation, not necessarily state-of-the-art.