The Maryland Board of Public Works denies access to ‘Potomac Pipeline” TOPICS:A Miner Detail PodcastColumbia GasPotomac PipelineThe Maryland Board of Public Works Posted By: Ryan Miner January 2, 2019 The Maryland Board of Public Works today denied Columbia Gas from using state property for a proposed gas pipeline under the Potomac River in Western Washington County. A Miner Detail Podcast discusses.