Quantifying Noise Impacts from ODOT Aggregate Source Operations

The potential listing of the sage grouse as “endangered” by United States (U.S.) Fish and Wildlife (expected in 2015) has the potential for significant impact to Oregon Department of Transportation (ODOT) aggregate source operations. Oregon Department of Fish and Wildlife (ODF&W) has issued a whitepaper in 2012 that provides interim guidance for mitigation for sage grouse habitat from activities associated with industrial commercial developments. Such developments include rock quarries. The interim guidance provides requirements for decibel thresholds, use of propagation models with output binned in 5- decibel contours, and recommended mitigation. It is unknown if activities from ODOT aggregate source sites comply with these very low noise thresholds. This uncertainty has potential impacts to development and delivery of projects in Regions 4 and 5 that depend heavily on material from ODOT quarries. Data are needed to determine compliance with the decibel thresholds and identify potential mitigation. There is also a great need to collect data for development of a methodology that can be applied throughout the state for determining noise impacts to sage grouse habitat and habitat for other noise sensitive species as well as other noise sensitive uses from rock quarries.