The Twomile Canyon Aggregate Area comprises the area drained by Towmile Canyon and includes 146 solid waste management units (SWMUs) and areas of concern (AOCs) located in 9 technical areas (TAs) at LANL. Of those 146 sites, 70 require further investigation and sampling to determine the nature and extent of contamination. Sites were potentially contaminated with both hazardous and radioactive components as a result of surface and subsurface placement of solid wastes, air emissions, effluent discharges, or detonation of explosives. From the beginning, the Twomile project had an estremely tight deadline of 20 days turnaround for all readiness documentation. Lakeworth successfully met this challenge by preparing all required documents and completing the necessary Permit Requirements within the short time allotted.
The Technical Area 15 (TA-15) Pulsed High-Energy Radiogrphic Machine Emitting X-ray (PHERMEX) Firing site was built in 1961 for High Explosive (HE) experimentation and served as LANL's primary hydro-test firing site for nearly forty years. Programmatic operations ceased at PHERMEX in 1998 and the facility has since been placed in shutdown mode. Prior to the shutdown, a significant amount of legacy contaminated shot waste had accumulated at the site and, since that time, additional contaminated equipment, waste, and shielding material from other firing sites was accumulated at PHERMEX. The legacy contaminated equipment, waste and shielding material required management and disposal at appropriate offsite landfill(s).
Lakeworth provided the Project Manager, Field Operations Manager, and Waste Management Specialist and subcontractor management for implementation of the NMED‐approved Phase III Investigation Work Plan for Material Disposal Area C. MDA C is an inactive 11.8‐acre landfill consisting of 7 disposal pits and 108 shafts, with the regional aquifer approximately 1320 feet below the ground surface. The objective of the 2010 to 2011 investigation at MDA C was to finalize chemical and radionuclide characterization begun in prior Phase I and Phase II investigations. Specifically, the Phase III investigation was performed to further characterize subsurface vapor concentrations of volatile organic compounds (VOCs) and tritium and to evaluate the potential for releases of contaminants to groundwater.
More than 300 investigation samples were taken from 200 discrete locations. To enable collection of all required samples, excavation of construction and demolition debris was required in some of the planned sampling areas. Inactive structures and piping consisting of an old acid waste sump, two concrete manholes, 400 ft of steel pipe, and 700 ft of cast iron pipe were removed as directed by the approved work plan. Lakeworth assisted in the boundary investigation of Material disposal Area A landfill and the survey and removal of the piping for General's tanks using heavy equipment. The investigation confirmed the depth and extent of the landfill pit boundaries, allowing project engineers to continue the planning process for pit excavation. The General's Tanks survey and removal consisted of inspection of the riser piping and removal of the remaining above ground fill and vent piping. Excavated debris and associated soils were containerized as waste and were handled in accordance with the approved Waste Characterization Strategy for the project.
After decades dominating the Los Alamos National Laboratory skyline, two water towers, one of them 66 years old and the other 38 years old (160-foot and 175-foot tall, respectively) were safely demolished by workers in a matter of hours recently, bringing EM’s Environmental Projects Office at Los Alamos a step closer to transferring the land for future commercial or industrial use. Workers safely brought down the towers using a controlled demolition method landing the towers in safe designated locations. Disposition of the materials left by the demolitions includes scrap-metal recycling. The towers were located in Technical Area 21 (TA-21), an early site of the Manhattan Project work at the laboratory, which is part of DOE's network of national laboratories. It was the location of the world’s first plutonium processing facility and where ground breaking tritium research took place.
The 2010 investigation activities included collecting soil, sediment, and rock samples from the surface to depths ranging from 10 to 50 feet below ground surface. A total of 207 surface and shallow subsurface soil, sediment, and rock samples were collected from 108 locations utilizing the hollow stem auger drilling method. Data from these samples were evaluated with data collected during a 2007 investigation. Lakeworth principals were also responsible for the 2007 investigation. The activities conducted in 2007 included the collection of 1255 surface and shallow subsurface soil, sediment, and rock samples from 407 locations, from the surface to a maximum depth of 39 ft below ground surface. The 2007 work was done within an extremely tight timeframe of less than 2.5 months. Three drilling crews and two hand auger crews were mobilized to safely and efficiently complete the project within budget and schedule.