Article VII of the New York State Public Service Law has a review process for applications to site, construct, and operate large-scale electric or natural gas transmission facilities. A transmission facility developer proposed to rebuild 12 miles of an above-ground electric transmission line and an adjoining substation in southern New York. In the middle of the permitting process, one reviewing entity issued a new guidance document that outlined sound study methodologies and sound level design goals for projects filing Article VII applications. This arrived after the initial sound level impact study was finished and the Article VII application was deemed complete for the project. Epsilon Associates, Inc., the acoustical consultant, revisited the sound model and then implemented mitigation in the form of a 30-foot-tall barrier for the proposed substation upgrade to meet the more stringent limits outlined in the guidance. Although the project was ultimately approved and constructed, additional time was spent both by the consultant and the developer which also accrued additional costs for the project attributable to this new guidance.