MAPPING ORPHANED AND ABANDONED OIL AND GAS WELLS IN TIOGA COUNTY, PENNSYLVANIA

The Pennsylvania Department of Environmental Protection estimates hundreds of thousands of oil and gas wells have been drilled in Pennsylvania since 1859. In these early explorations drilling was conducted with scarce oversight or regulation, resulting in little documentation. As these wells became unprofitable, they were abandoned or plugged improperly, and often lost. Thousands of these legacy wells were never decommissioned and pose both fire and safety hazards, as they provide potential pathways for groundwater contamination. Likewise, these unchecked wells release methane gas, which has extensive radiative-forcing properties that drastically change climate and pose explosive potential when drilling modern unconventional wells. This demands the creation of a centralized, georeferenced, searchable database of oil and gas well locations in the county, which is achieved via compilation of available archival records, company maps, and field methods.

This research is guided by two project objectives: create a georeferenced database of searchable wells, and mitigate those unplugged wells using state funding. Records were compiled from existing databases and previously unrecorded documents, then geolocated by converting old state plane coordinate systems to more accurate modern vertical datums using ESRI software. Initial field verification showed the older survey systems to be off by hundreds of feet, making location of wells impractical. High-resolution imagery, such as Google Earth, LiDAR, and orthophotography, were used to pinpoint possible field positions. Current methods of location involve expensive and time-consuming surveys using backpack magnetometers or electrical resistivity. This research contends ground-penetrating radar provides a time-efficient, alternative method for geolocating these abandoned and orphaned wells that have become an increasingly important regional environmental and public health concern. Metal detectors and geophysical surveys are performed using Mala 100 and 500 MHz antennas. Post-processing and analysis of radar data is conducted using GPR-Slice.