Fifteen years of regional monitoring by the New England Seismic Network indicated a locally high level of seismicity near South Sebec, between the towns of Milo and Dover-Foxcroft in central Maine. Most of the events were located in a diffuse zone south of the distinctive, ENE trending Harriman Pond Fault (HPF) which is indicated by brittle deformation in outcrop and is represented as a depression in topographic maps and satellite images. A portable network consisting of both digital and analog instruments was deployed during the summers of 1989 and 1990 in order to characterize the pattern of the microearthquakes and to determine high-resolution epicenters, depths, and fault plane solutions. Seventy-three events were detected during the experiment, of which 28 could be located. Many of the events south of the fault lie along a NNW trending line which has no major expression in the surface geology. Only, a few of the events are subparallel to the HPF. The first motion data were insufficient for the determination of any fault plane solutions.