[en] Effective on March 15, 1990, the Environmental Protection Agency established regulations controlling the emission of radionuclides to the air from Department of Energy facilities to limit the dose to the public to 10 mrem/yr. These regulations are detailed in 40 CFR 61, Subpart H, open-quotes National Emission Standards for Emissions of Radionuclides Other Than Radon from Department of Energy Facilitiesclose quotes. Part of these regulations require the operation of sampling systems on stacks meeting certain requirements. Although Los Alamos National Laboratory has a long history of stack sampling, the systems in place at the time the regulation became effective did not meet the specific design requirements of the new regulation. In addition, certain specific program elements did not exist or were not adequately documented. The Los Alamos National Laboratory has undertaken a major effort to upgrade its compliance program to meet the requirements of USEPA. This effort involved: developing new and technically superior sampling methods and obtaining approval from the Environmental Protection Agency for their use; negotiating specific methodologies with the Environmental Protection Agency to implement certain requirements of the regulation: implementing a complete, quality assured, compliance program; and upgrading sampling systems. After several years of effort, Los Alamos National Laboratory now meets all requirements of the USEPA