Portland, OR-based NW Natural is moving ahead with preliminary design, analysis and economic assessments for the expansion of the utility’s Mist underground gas storage facility in northwest Oregon to support new generation units planned by Portland General Electric (PGE) at its Port Westward gas-fired complex. The gas utility is now finalizing a request for approval of a rate for the storage services from the Oregon Public Utility Commission. The project would include development of new storage wells, a compressor station and pipelines. NW Natural is preparing budget estimates to review with PGE leading up to a mutual decision on whether to proceed. A decision is expected by the end of the year.