Abstract

Springs within the Fishlake National Forest of central Utah supply groundwater to 16 local communities, 193 stock watering facilities, and numerous recreation sites. Seismic surveys for petroleum exploration are viewed locally as a potential threat to unimpaired spring flow. To provide adequate protection, the Fishlake National Forest employs an acceptable vibration zone approach. It limits proximity of explosive charges to springs based on peak particle velocity. Current research indicates little likelihood of damage where peak particle velocities are less than 2 inches per second. The Fishlake National Forest achieves adequate protection for explosive charges of 50 pounds or less with a minimum zone that is 350 feet around a spring. For larger size charges, a nomogram provides the increased radius of the acceptable vibration zone. The risk of spring damage is reduced to an acceptable level while posing no great impediment to seismic survey work.