A helicopter that has been flying low over the Columbia River several times a day is conducting work on a Hanford project, according to the Department of Energy.
The flights, which circle over the Columbia River four to six times each day, are expected to continue until about Oct. 1.
A radiological survey is being conducted from the air on waste burial grounds in central Hanford as one step toward developing an environmental cleanup plan.
Hanford contractors have previously used helicopters to collect data on the extent of radiological contamination more efficiently than having crews walk the land.
The helicopter flies over the Columbia River between the blue bridge and Bateman Island to take measurements of background levels of radiation at the beginning and end of each flight over central Hanford burial grounds.