Water Application for Dust Control in the Central Plateau: Impacts, Alternatives, and Work Strategies

Dust control is needed during many activities at the Hanford Site for health and safety purposes and to prevent contaminant dispersal via atmospheric transport. Spraying of water is the baseline approach at the Hanford Site for dust control in most applications, including use during excavation activities, on roadways and disturbed areas, for facility demolition, and during construction activities. Use of water at or near waste sites may introduce infiltration to the subsurface. As such, the recharge rate (hydraulic driving force) through the vadose zone and to the groundwater may be increased by an extent related to the duration and amount of water applied. An increased recharge rate can increase contaminant fluxes toward the groundwater and potentially induce lateral movement depending on the magnitude of the recharge rate. Thus, dust suppression via water spray is of potential concern for contaminants in the vadose zone. Because Hanford remediation work is transitioning from the River Corridor to efforts on the Central Plateau where there is a significant inventory of contaminants in the vadose zone, dust suppression approaches for these efforts will need to understand the potential negative effects of water addition.