The main objective of radioactive waste management is to protect workers, the public and the environment from the potential harmful effects of radioactive waste and to minimize the burden for future generations.
December 7, 2022 Project Update
The planned venting of headspace gas in four flanged tritium waste containers is awaiting the necessary regulatory approvals and warmer temperatures. When the approvals have been received and the pre-venting processes have been completed, the National Nuclear Security Administration and Triad National Security LLC, the management and operating contractor for Los Alamos National Laboratory, will schedule the venting for a time when sufficiently warm temperatures allow for operations to proceed.
A Flanged Tritium Waste Container (FTWC) is a stainless-steel certified pressure vessel designed for long-term storage of tritium-contaminated waste items. The Laboratory is planning to vent headspace gases from four of these containers.
Questions and Answers
This question and answer list is in response to the inquiries NNSA received by email and during the second public information session held November 5, 2020. Many new questions are addressed here, with similar questions condensed, consolidated, or paraphrased. Duplicate questions have not been repeated, but are still available in the "Additional Questions and Answers" section that follows this one. Our answers are intended to be fully responsive to the broader intent of every question we received.
1. Can you vent without the NMED Temporary Authorization?
No.
2. Where is this activity addressed in the Consent Order?
The FTWCs are not addressed in the Consent Order, as they are not categorized as legacy waste. They are located at Technical Area 54's (TA-54) Area G, and their removal is necessary to support larger waste reduction goals.
3. Will you vent four days in a row?
The operation to mitigate the pressure in the four FTWCs is planned for two days per container, for a total of eight days. Those days may not be consecutive to allow for contingencies such as other operations and inclement weather.
4. How is the higher risk tritium in oxide or vapor form (HTO) being mitigated?
The molecular sieve material in the capture system of the FTWCs is specifically engineered to capture HTO.
5. What are the cumulative impacts from this release?
There are no cumulative impacts from this operation. All limits are conservative, and well within regulatory limits that are protective of the public.
6. What alternatives have been considered for this operation?
Numerous alternatives were considered in the design of this project, with an overview of those alternatives discussed in the public information sessions and the first question and answer document posted on the LANL Website and the Electronic Public Reading Room. Permanent disposition of this waste supports waste and risk reduction priorities for the DOE and regional stakeholders. Disposition alternatives and strategies considered included leave in place, transportation without pressure mitigation, and pressure mitigation before transportation.
Additional strategies considered included placing the containers in a secondary and tertiary containment, and numerous pressure mitigation and capture strategies. The selected option, while more complex and expensive than many alternatives, was deemed to be the safest option for both the workers and the public. All aspects of the design are engineered to maximize safety, capture efficiency, and minimize additional waste generation.
7. Have you analyzed the specific impacts to communities in the area?
We have evaluated potential doses for this operation, and all LANL operations, at a variety of locations in and around LANL, including Santa Clara Pueblo and San Ildefonso Pueblo. Radiological dose consequence at these areas is less than one-tenth of the dose that would be received by the hypothetical maximally exposed individual (MEI) in White Rock. Limits calculated for the White Rock MEI will therefore be protective of all population centers.
8. How can you say that site limits cannot be exceeded?
Only one container at a time will be vented, and the inventory of a single container, even with 100% of the headspace gas released, would not exceed the permit limits. Additionally, real time monitoring is in place to monitor the operation, and the process can be paused and placed in a safe configuration at any time as needed.
9. What is the EPA’s role in this project? The NMED?
EPA Region 6 approves the air emissions permit request for this project, and the NMED approves the treatment process as these containers are Resource Conservation and Recovery Act (RCRA)-regulated waste. LANL also uses the EPA’s Clean Air Act Assessment Package - 1988 (CAP-88) emissions models. This operation would require the same permits and approvals, regardless of the specific design of the process, anticipated release quantities, and timing of the operation.
10. What is the effectiveness of the capture system?
Effectiveness of the capture system can vary by container contents, pressure release rates, and temperatures. The project’s goal is to perform the operation in a manner that maximizes capture effectiveness and keeps any potential release as low as reasonably achievable. The real time monitoring system ensures these goals are met.
11. We’ve heard three numbers for potential dose: 20 mrem, 10 mrem, and 8 mrem. Can you explain?
The permitting process requires analysis of the worst-case scenario. For this project, that would be a 100% release of the contents of all four containers (approximately 114,000 curies) with no mitigation or capture. That is not a realistic or possible scenario, since the operation is designed to only vent the hydrogen, oxygen, and small quantities of tritium in the headspace of each container, a very small fraction of the total contents, and only one container at a time. In this worst-case, bounding scenario, the Maximally Exposed Individual (MEI), under the least favorable meteorological conditions, could receive 20 mrem. As previously stated, this is not a likely scenario, and only used for a worst-case bounding criteria.
The site release limit for all airborne radionuclides, combined from all LANL operations, is 10 mrem per year to any Maximally Exposed Individual member of the public.
This specific project has set a limit of 8 mrem for the entire operation at the site boundary for the MEI. However, the project’s goal is to limit any release to the lowest possible quantity to achieve a safe configuration for transport. The desired and likely offsite dose for this project will be extremely low – below the 8 mrem, possibly even 0 mrem, at the site boundary.
12. What will the Laboratory do if the site limit is exceeded?
In the very unlikely event that the site limit is exceeded, LANL would make the required formal notifications to all regulators, and follow the established processes defined in state and federal regulations.
13. What is the difference between Triad and N3B?
Triad is the management and operations (M&O) contractor for the NNSA and operates the majority of LANL operations. N3B is the legacy cleanup contractor for DOE EM and manages operations at TA-54 Area G, where the four FTWCs are located. This project is a joint operation, with collaboration between the two DOE entities (NNSA and DOE EM) and the two contractors, Triad and N3B. Triad is responsible for the operation, and N3B manages the site where the FTWCs are located.
14. Have you performed “puff” modeling?
An evaluation of the CALPUFF code in comparison with our standard CAP-88 code completed in 2002 showed that CAP-88 is conservative for distances over 300 meters from the source. At the distances applicable for this project – 2100 meters or more – the use of CAP-88 will be a conservative estimate of radiological dose.
15. Is LANL considering plant, animal, and soil impacts?
16. What is the urgency for this project? Is there a financial incentive or bonus for completing the project by a certain time?
There is no urgency for this project beyond the broader mission goals to reduce onsite waste liabilities. This project has been in development for approximately four years, and will not proceed until all approvals and permits have been obtained. There is no financial incentive tied to the disposition of these containers.
17. How are these FTWCs different from WIPP drums? These four containers hold different constituents. They are not transuranic waste, which is the type of waste that is stored at WIPP.
18. How will you make data and results available to the public in real time, that is, as soon as you have final results?
Emissions results from the operation will be posted in the Electronic Public Reading Room (ePRR) and the ASER. Additionally, an EPA representative will attend the operation. Results will be published in a timely manner in accordance with federal reporting processes.
Additional Questions and Answers
Q. What is a Flanged Tritium Waste Container and why do you need them?
The main objective of radioactive waste management is to protect workers, public and the environment from the potential harmful effects of radioactive waste and to minimize the burden for future generations. An important task for waste management is to translate general waste acceptance requirements into detailed waste package specifications. Flanged Tritium Waste Containers (FTWCs) are specifically designed to provide radiation shielding and/or physical containment to restrict or prevent the spread of contamination as an engineered component for ensuring the safe management of radioactive waste.
Q. What is tritium and what is it used for?
Tritium is a radioactive form of hydrogen gas and an important component in nuclear weapons.
Q. Why are these drums at Area G?
These FTWCs were packaged at LANL’s Weapons Engineering Tritium Facility (WETF) in 2007 and sent to Area G for permanent disposal.
During an audit of containers, NNSA identified a small amount of lead in the materials inside the FTWCs, resulting in the containers being designated as hazardous waste under the Resource Conservation and Recovery Act (RCRA) and requiring offsite disposal. Further analysis identified the potential for a flammable, pressurized mixture of hydrogen and oxygen in the FTWC headspace, requiring venting of headspace gases to enable personnel to safely move the containers.
Laboratory engineers have done a careful analysis of the venting process to ensure that any releases are carefully controlled. The system pictured here, has been specifically engineered to capture the form of tritium expected in the FTWC headspace.
Q. Why is venting necessary?
The Laboratory has a goal of reducing the volume of waste on site. As part of this effort, the four FTWCs were identified for treatment on site and eventual shipment to a licensed off-site facility. Before the containers are moved to WETF, pressure built up inside must be relieved. Once the pressure is relieved, the containers will be transported to WETF for further treatment prior to shipment to a licensed off-site facility.
Q. Why are you doing this now?
NNSA is conducting these activities to support safe operations at LANL, including mitigating risks to the public and the environment, and to enable the disposition of radiological and hazardous waste as required by our permits and DOE Orders. These operations are being conducted in compliance with all applicable regulatory requirements.
Q. When do you plan to vent the containers?
Venting of the drums was previously postponed indefinitely due to impacts of the COVID-19 pandemic. NNSA and Triad are working with regulatory agencies to determine a revised schedule.
The operation will be conducted with the utmost considerations for safety to Laboratory employees, the public and the environment.
Q. Is there any danger to public health and safety?
No. Our engineers have a proven safe and effective method to vent the FTWCs under carefully controlled conditions. Additionally, only one container at a time will be vented, and the venting process will undergo real-time monitoring to ensure DOE and Environmental Protection Agency (EPA) requirements on radioactive dose limit are not exceeded. The operation will be conducted with the utmost considerations for safety to Laboratory employees, the public and the environment.
Q. How do you know venting is safe?
Laboratory engineers have done a careful analysis of the venting process to ensure that the release is controlled. The process has been tested at WETF and proven effective. This methodology has been evaluated and observed by representatives from the EPA who will be monitoring the effort. Additionally, strict limits have been placed on the amount of tritium that can be released and we will be monitoring closely to ensure those limits are not exceeded.
Throughout the process, Laboratory engineers will carefully monitor the amounts of tritium released. We have also developed a system to capture much of the gas while it is being released. Strict regulatory limits prevent releasing more than the amount allowed for each individual container. These precautions are designed to prevent any off-site health impacts.
The ventilation system used is carefully monitored for contamination during assembly and disassembly. These and other precautions are designed to prevent any on-site and off-site health impacts.
Q. How many FTWCs will be vented?
There are four containers.
Q. What is the process?
Each of the four containers will be vented separately, one at a time, at TA-54's Area G. The venting process will allow the vast majority of the tritium to be captured through a dedicated filtering system designed for tritium capture. We also have a real-time monitoring system integrated into the exhaust and emission system.
Q. Are there other ways to treat this waste that does not involve releases to the atmosphere?
No. NNSA has been working with the regulators to determine the safest method to enable movement of these containers from TA-54 to WETF for further treatment and shipment to a licensed off-site disposal facility. WETF has all the appropriate infrastructure to safely manage tritium.
Q. Why not do the venting at WETF instead of Area G?
The purpose for the venting is to enable us to safely move the drums from Area G to WETF, where we have the appropriate infrastructure to further treat and safely manage tritium.
Q. What is the distance between Bldg. 1028 at TA-54, where the containers are stored, and the nearest resident in White Rock?
It is 2200 meters from Bldg. 1028 to the closest business or residence location in White Rock; about 1.3 miles.
In addition to the monitoring equipment we are using to measure the release, the Laboratory has four air monitors in White Rock to ensure that we track any radioactive particles that may reach the area. The data will be available in our annual emissions report to the EPA and in our ASER.
Q. How are emissions monitored and evaluated?
To predict the off-site dose consequences from these releases, we are using worst-case computer models to establish daily emissions limits. At the end of each day of operation, we recalculate this dose consequence using actual wind from that day. The process then repeats, using worst case modeling to ensure no limits are ever exceeded. This ensures the protection of our personnel, the public, and the environment.
Q. Where are the relevant White Rock air monitors?
We have four monitors in White Rock: at the bottom of Pajarito Road, at the old White Rock Fire Station (Rover & NM-4), at “Rocket Park,” and near Pajarito Acres (Monte Rey South & NM-4). These all measure airborne radioactive particulates and tritium oxide. The data will be available in our annual emissions report to the EPA and in our ASER.
We have real-time monitoring to prevent a release from exceeding established limits.
Q. Can you confirm that the highest dose possible off-site is estimated at 20 millirem?
Yes. For EPA planning purposes, we modeled the entire contents of the four FTWCs released to the air, using average wind conditions and no filtering system. This resulted in the 20 millirem off-site dose. In reality, we will not be venting the entire contents – just that fraction which is in the headspace of the four containers. The operations will take place in a slow, controlled manner, using filtration to remove as much tritium as possible.
NNSA will monitor the releases to ensure we stay well below the EPA limit of 10 mrem per year. We will not conduct operations in adverse wind conditions.
NNSA has developed plans to ensure that the 10 mrem level will not be reached by using emissions controls (filters) on the exhaust system and actively monitoring the emissions in real-time. Operations will not occur if the wind speed and direction are unfavorable.
Venting will be conducted in a controlled manner to enable monitoring and control of the pressure in a manner that maintains the safety of our personnel, the public and the environment.
Note: Background radiation dose in this part of Northern New Mexico is about 1 mrem per day or more – about 350-400 mrem per year. The EPA and the Clean Air Act allow DOE facilities to emit radioactive material that could contribute up to 10 mrem per year above this background level. LANL’s emissions for the past several years have been a fraction of 1 mrem per year. For comparison, a cross-country round-trip airplane flight results in about 3.7 mrem of radiation exposure.
Q. What agencies are overseeing this process?
The EPA for radiological air quality emissions, the NMED for RCRA treatment, and federal regulators from the DOE for radiological emissions.
Q. What happens to the four FTWCs when the venting is complete?
They will be safely transported to another location on-site at LANL where the contents will be repackaged into Department of Transportation-compliant containers and then shipped offsite to a licensed storage facility.
