NSF SAK Peak JA redacted Copy signed

National Science Foundation
401 Dulaney Street • Alexandria, Virginia 22314

CUI//SP-CONTRACT

2026

JUSTIFICATION AND APPROVAL

SUBJECT: Justification for Other Than Full and Open Competition for Structural Engineering and Liquid Mercury Removal and Remediation Services for the Dunn Solar Telescope (DST)
The purpose of this memorandum is to capture, in accordance with FAR Part 6 requirements, the circumstances and rationale supporting the use of other than full and open competition for a sole source contract award for emergency engineering and hazardous materials services. This memorandum is a product of the known facts and circumstances during the period in which it was written.
Pursuant to the requirements of the Competition in Contracting Act (CICA) as implemented by the Federal Acquisition Regulation (FAR) Subpart 6.1 and consistent with the content requirements of FAR 6.104-1(a) the following facts and rationale justify the use of such authority.
6.104-1(a)(1): Agency and Contracting Activity.
The National Science Foundation, Office of Chief Financial Officer, proposes to issue a contract on behalf of NSF Office of Research Infrastructure (NSF ORI), on a basis of other than full and open competition, for the award of a 12-month contract for structural engineering, liquid mercury removal, and remediation for the Richard B. Dunn Solar Telescope (DST).
6.104-1(a)(2): Nature and/or description of the action being approved. The intent of the U.S. National Science Foundation (NSF) is to do an immediate forensic engineering assessment of the structural integrity of the Dunn Solar Telescope and rapid hazardous materials remediation due to a large liquid mercury leak and the potentially imminent environmental and safety risks inside the telescope. The source of the leak is not yet addressed; therefore, time is of the essence to halt the leak, stabilize the structure, drain the remaining liquid mercury, remediate any environmental hazards, and conduct selective interior demolition of the interior elements of the tower (i.e., the mercury-containing vacuum tube and related components).

BACKGROUND

Description of the Dunn Solar Telescope
The DST, built by the US Air Force in 1969, is located at NSF’s Sacramento Peak Observatory. It took approximately 10 years to construct due to the complexity and scale of the project. The following provides a description of DST features: x

DST extends to 136 feet above ground and 228 feet below ground.

x

Vertical vacuum tube for the telescope is enclosed within a concrete tower with 3foot-thick walls and is supported by three oversized screws.