Congressional Budget Office Cost Estimate: H.R. 4475, National Volcano Early Warning and Monitoring System Act [open pdf - 108KB]
From the Summary: "H.R. 4475 would authorize the appropriation of $15 million for each year over the 2018-2024 period for the U.S. Geological Survey (USGS) to establish a system to improve monitoring of active volcanoes. The bill also would direct USGS to conduct a study on the feasibility of establishing volcano observatories in the U.S. Pacific Island territories and would authorize USGS to enter into cooperative partnerships with states, territories, universities, and agencies to implement the system."
Congressional Budget Office: http://cbo.gov