B09_Amend_0003_Att_338223_Lead_Paint_Testing_Results_0003.pdf

This is an email chain documenting lead-based paint testing results on three bridges within Yellowstone National Park. Darren Parsons from the National Park Service conducted XRF (X-ray fluorescence) gun testing on the No Name Bridge near West Thumb, West Thumb Creek Bridge, and Lava Creek Bridge during May 18-19, 2026. The testing measured lead paint concentrations on various bridge components including railing posts, top railings, bottom railings, and spindles.

All tested components across the three bridges exceeded the federal threshold for lead-based paint, which is defined as paint with lead levels greater than or equal to 1.0 milligram per square centimeter (mg/cm²). Test results ranged from 4.84 to 5.0 mg/cm², with the XRF gun's measurement ceiling at 5.0 mg/cm² noted as potentially understating actual lead levels. All measured areas failed the lead-based paint standard. The email indicates the sender's intention to train Sally Bartindale on XRF gun operation and provide access to training videos from Evident, enabling future lead-based paint testing during project planning trips without external contractor involvement. The communication was distributed to the Bridge Preservation Team at Yellowstone National Park for action planning regarding the identified lead-based paint contamination.