Groundwater contamination due to migration from a natural gas well along natural fractures resulted in benzene and methane in surface water and groundwater. After several years of operating a sparge system with little progress, Rule was selected to provide remediation for the site. Our evaluation concluded that the existing system was not effective and in fact due to the high groundwater flow rates in the aquifer, natural attenuation processes were adequate to control the plume migration. The case for monitored natural attenuation supported by fate and transport modeling was presented to the COGCC and the proposal to shut off the system and reduce the monitoring program was approved. Rule continues to monitor the groundwater with the data supporting our conclusions for natural attenuation and reduce the ongoing costs for our client.