Bittersweet: Idaho Employee Supervises Closure of Building Where His Career Began

IDAHO FALLS, Idaho – As a twentysomething operations technician, Mark Henderson thought he would work in the Transuranic Storage Area-Retrieval Enclosure (TSA-RE) at DOE’s Idaho National Laboratory (INL) Site for his entire career.

Today, a far more seasoned and experienced Henderson — now a Resource Conservation and Recovery Act (RCRA) project manager for EM contractor Idaho Environmental Coalition — is overseeing the initial steps of RCRA closure that will lead to the eventual demolition and removal of the aircraft-carrier-sized building at the site’s Advanced Mixed Waste Treatment Project (AMWTP).

Construction of the TSA-RE, Waste Management Facility-636, was completed in 1995 to cover above-ground stored transuranic waste. The facility covered 7 acres of transuranic waste, stacked 16 feet high. Most of the waste had been shipped to the INL Site from the now-closed Rock Flats Plant near Denver, Colorado, in the 1970s and early 1980s.

At one time, more than 54,000 cubic meters of waste was stored in drums and boxes, stacked on asphalt pads and covered with an earthen berm under the TSA-RE roof. The waste in the drums and boxes was comprised of items that had come in contact with radioactive elements, such as tools, wood, paper and protective clothing.

Three asphalt pads are under the TSA-RE roof: Pad 1, Pad R and Pad 2. The initial RCRA closure work has crews removing asphalt from Pad 1 and Pad R.

They are removing the asphalt with heavy construction equipment and have safely cleared about 70% of the asphalt flooring, all while being outfitted in anti-contamination personal protection equipment and respiratory protection. Once the asphalt is reduced to manageable pieces, it is loaded into containers that are transported to the onsite Idaho CERCLA Disposal Facility for disposal. CERCLA stands for the Comprehensive Environmental Response, Compensation and Liability Act.

Pad 2 will continue to be used to store treated and packaged waste awaiting shipment to EM’s Waste Isolation Pilot Plant (WIPP) for permanent disposal. Approximately 3,000 cubic meters of stored waste remain in TSA-RE on Pad 2, which will go to WIPP or other offsite disposal facilities.

Henderson manages a crew of early-career employees who are working in a contaminated facility for the first time.

“They’re young and motivated and they’re amazed to be working on a job where safety drives everything we do,” Henderson said. “If there is a concern, we take a pause and discuss the situation. We let them know this is the right way to do work and the way I’ve been doing it ever since I was their age.”

And his approach to the job has kept the RCRA closure work ahead of schedule and under budget. The initial phase of the asphalt removal is scheduled to be completed in March 2023.
Henderson will be moving from managing the AMWTP RCRA closure project to a new job as tank farm vulnerabilities/closure project manager at the site’s Idaho Nuclear Technology and Engineering Center.

It’s a bittersweet time for the 20-year employee of the INL Site.

“I’ve had so many experiences in TSA-RE and AMWTP, so many challenges, so many interesting experiences retrieving and treating waste,” Henderson said. “I hate to see it come down, but that’s the nature of cleanup work.”