The Department of Defense, specifically the Department of the Army, is seeking sources for Environmental Proficiency Testing Services to support the DOD Food Analysis and Diagnostic Laboratory at Brooke Army Medical Center in Texas. The procurement aims to identify responsible sources capable of providing proficiency testing for various contaminants in potable drinking water, ensuring that results are accurate, traceable, and reproducible. This service is critical for maintaining the integrity of laboratory results, which may be used in legal contexts. Interested small businesses, including those that are 8(a), Service-Disabled Veteran-Owned, HubZone, and Women-Owned, are encouraged to respond by emailing Wayne V. Thompson at wayne.v.thompson3.civ@health.mil by June 2, 2025, at 10:00 AM CST. The estimated size standard for this opportunity is $19 million under NAICS code 541380.