A subcommittee of the house science committee will hold an oversight hearing today.
Udall and other members of Colorado's Congressional Delegation have been monitoring the situation at the National Institute of Standards and Technology in Boulder.
About one-quarter gram of powder containing plutonium spilled in the lab last month when a vial cracked. One of the scientists washed his hands in the sink, sending a small amount of plutonium down the drain into Boulder's public sewer system.
Officials say a few employees had internal plutonium exposure, which can lead to cancer.
Radiation was found in two buildings but officials say no threats to public health or the environment have been identified.