DOE/SRS contract official unable to address timeline for removal of surplus plutonium from the Savannah River Site.

Twenty-five years after issuing its first decision pertaining to the nation’s 50 metric ton (MT) surplus plutonium stockpile, the Department of Energy’s (DOE) disposition program continues to, as SRS Watch has described, limp along and remain characteristically uncertain. Three weeks ago the head of DOE’s Savannah River Site’s (SRS) primary operating and management contractor could not provide a timeline for processing and removal of 9.5 MT of plutonium from storage at SRS to the Waste Isolation Pilot Plant (WIPP) plutonium waste repository in New Mexico.

At the current rate of processing, the site will not be able to meet its 2037 deadline for removing 9.5 MT of surplus plutonium per the “Plutonium Settlement” agreement between the Federal Government and the State of South Carolina, and some materials could remain well past the 50-year long-term storage period selected by DOE in 1997.

by Don Moniak
May 19, 2024

Savannah River Nuclear Solutions (SRNS) is the primary management and operations contractor at the Department of Energy’s (DOE) vast Savannah River Site (SRS), where more than ten tons of plutonium (Pu), of which more than 90 percent is surplus to U.S. nuclear weaponry needs, is presently stored within the site’s repurposed, seventy-year old K-Reactor building; now referred to as K-Area.

There were approximately 11.5 Metric Tons (MT) of plutonium within ~5,000 containers stored at K-Area in 2019 (Figure 1), of which 10.5 was surplus material shipped to SRS from other sites (1). DOE asserts that 1.0 MT of material was removed since then, leaving 9.5 MT of plutonium that must be removed by 2037 under the terms of the 2020 DOE/State of South Carolina “SRS/Plutonium Settlement.”

At the April 29, 2024 South Carolina Nuclear Advisory Council (2) meeting, SRNS President Dennis Carr recently updated the group on the major programs and missions at SRS that are under SRNS purview. His presentation focused on plutonium pit production (3), surplus plutonium disposition, and production and management of tritium for the nation’s nuclear weapons arsenal.

The surplus plutonium disposition portion featured an uninspiring report on the slow pace of plutonium disposition at SRS. Since fully implementing a program known as “dilute and dispose,” in 2021, only 0.123 metric tons (MT) of the ~10.5 MT of surplus Pu stored at SRS has been processed into a waste form and sent to DOE’s Waste Isolation Pilot Plant (WIPP) in New Mexico for disposal.

Less than 0.3 metric tons per year are currently being processed at K-Area; much of it awaiting approval for shipment to WIPP. The processing pace is not expected to pick up until after 2030, and only if an $800 million project to add two glovebox processing lines is completed.

At the end of the surplus plutonium discussion, State Senator Tom Young (R-Aiken) asked Mr. Carr a simple question that proved to be the most difficult of the meeting:

“Do you know the projected timeline when all the (surplus plutonium) material will be disposed of?”

Mr. Carr’s answers were, in order:

“I don’t.”
“It is beyond my knowledge base.
“We will have to get back to you.”

No other DOE official stepped up to the podium to assist with an answer. Nor did any other member of the Advisory Council ask a followup question.

The lack of answers and absence of additional questions were intriguing and astounding for two reasons; both of which involved omissions of important information.

First, the $600 million Plutonium Settlement reached in August, 2020, between the federal government and the State of South Carolina mandates a removal date of 2037 for the 9.5 Metric Tons (MT) of the surplus plutonium that was shipped from other DOE sites and is currently stored at SRS (1). If the deadline is not reached, DOE will face a new set of hefty fines from the State of South Carolina. The lack of additional questions suggests that the settlement agreement is increasingly less of a priority issue for the advisory council or DOE/SRS.

Second, just ten days before the meeting DOE’s National Nuclear Security Agency (NNSA) had issued its Record of Decision (ROD) for the Final Environmental Impact Statement for the Surplus Plutonium Disposition Program (SPDEIS), a decision that will help guide the DOE/NNSA surplus plutonium management for the foreseeable future. (A Summary of the SPDEIS provides more detailed justification for the ROD).

As described in Feds Propose Moving ~27 tons of Plutonium to SRS, the latest Surplus Plutonium Disposition EIS process explored the impacts of disposing of 27-34 metric tons of surplus plutonium currently stored within the sealed nuclear explosives components known as “plutonium pits,” as well as surplus plutonium metal not within pits. There is an estimated 11,000 to 14,000 surplus pits presently in storage at the Pantex Nuclear Weapons Plant near Amarillo, Texas.

The preferred alternative involved four subalternatives to disassemble the pits and convert Pu metals to a powder in a modern Pit Disassembly and Processing Plant (PDP), process the powder into a transuranic waste form via the dilute and dispose method, and then ship the waste to the Waste Isolation Pilot Plant (WIPP) for underground disposal.

Within the preferred alternative, DOE/NNSA EIS considered four different alternatives to accomplishing that goal: two versions of processing at both Los Alamos and SRS, an all-in-one Los Alamos processing program, and an all-in-one SRS processing program. WIPP and dilute and dispose were the only constants. (A “No-Action” alternative received only cursory, gratuitous review, as the U.S. remains committed to converting its plutonium stockpile into a waste form that inhibits, but does not prevent, re-use of plutonium for our nuclear arsenal.)

The Record of Decision was more of an indecision amounting to the federal government continuing to not do much with surplus plutonium, other than keep it in storage. Most notably, DOE/NNSA failed to select a processing sub-alternative, leaving the preferred alternative as more of a theoretical than real pathway. (Figure 3).

DOE/NNSA further kicked the surplus plutonium program further down the road by formally announcing a previous decision, first reported by Savannah River Site Watch in October 2023, to delay the Pit Disassembly and Processing plant by at least one decade, writing,

“Increased capacity for producing plutonium oxide, which NNSA evaluated as part of the Preferred Alternative in the SPDP EIS, will therefore be delayed. This decision will extend the timeline for the full 34 MT disposition mission.”

In short, the DOE/NNSA plutonium disposition program will continue to limp along at a relatively glacial pace of about 1 MT every 3-4 years.

What this means for the Central Savannah River region, as well Americans along the transportation route from Los Alamos, is far less surplus plutonium being shipped to SRS than if a PDP was constructed; and a greatly reduced likelihood of another Pu processing facility being located at SRS. Depending on an individual’s outlook on the prospect of more plutonium processing at SRS, the indecision and facility delay can be either good or bad news.

In the absence of an answer from DOE/NNSA to Senator Young’s question, the following letter estimating the rate of Pu removal from SRS was sent to Senator Young via email the day after the Nuclear Advisory Committee meeting. The letter was later forwarded to the SRS Citizens Advisory Board.

Dear Senator Young, 

Regarding your unanswered question on the timeline for surplus plutonium disposition posed to SRNS President Dennis Carr during the Nuclear Advisory Council meeting on Monday: “Do you know the projected timeline when all the (surplus plutonium) material will be disposed of.” 

There is no good answer, which might be why Mr. Carr could only answer “I don’t,” and “it is beyond my knowledge base.” I do not think there will be a good answer, either, because: 

a. Ultimate removal from SRS is entirely dependent upon the availability of WIPP, and that is not under the control of SRS; and

 b. Removal in a manner that meets the Pu settlement mandate of 9.5 MT by 2037 is heavily dependent upon DOE/NNSA’s commitment to the $800 million program to increase plutonium dilution to TRU waste production rates by adding three more gloveboxes by FY 2031. 

Even if WIPP were not an issue, at the current rate of work at K Area, it would take DOE/SRS 19-20 more years to remove 9.5 MT of surplus Pu; assuming a steady increase in production rates and an absence of accidents, budget cuts, and other unforeseen circumstances. 

These estimates are based upon the following: 

1. Under the Pu storage settlement agreement, DOE/SRS is required to remove 9.5 MT of surplus Pu by 2037.  (This will leave ~1.0 MT of nonsurplus Pu in place, which was the approximate SRS non surplus Pu inventory before shipments from other sites began in 2002).  

2. At the end of 2019 there was an estimated ~11.5 MT at SRS. DOE/SRS reports accomplishments in terms of 3013 storage containers (aka cans) which contain an average of 2.3 KG of Pu per container. So the best way to track this is by number of storage containers, of which there were ~5,000. (This graphic was presented to the SRS CAB in July 2022). 

3. Assuming 9.5 MT = 4,130 cans, at the current rate of processing Pu into a diluted Transuranic Waste (TRU) form, it would take DOE/SRS ~20 years to complete the conversion process. This assumes that WIPP will be able to accept the waste at the same rate, which is a whopper of an assumption. The rest of this estimate relies on the rosy assumption of gradual increases in production from current rates. 

a. Since 2022, when downblending into a TRU waste form began, the 5,000 can inventory has been reduced by 321 cans (91 in 2022, 110 in 2023, and 120 expected in 2024), leaving ~4,700. If one assumes that all of the converted Pu was part of the 9.5 MT, then ~3820 cans remain to be processed to meet the Settlement Agreement. 

b. Processing is limited by equipment, and currently there is only one glovebox line available. The goal is to increase rate of production by 10 pct each year, with the FY 2024 goal of 120 cans. If production were increased by 10 pct each year, which is a rosy forecast, production might look like this: 

FY 2025: 132 cans

FY 2026: 145 cans

FY 2027: 160 cans

FY 2028: 176 cans

FY 2029: 194 can

FY 2030: 213 cans

So under the current goals of ten percent increase per year, another 1020 cans might be processed through FY 2030, barring accidents, budget cuts, and/or other unforeseen circumstances. 

That will still leave 2,800 cans that would require processing by 2037. 

c. Without any new production capability, it will take another 13 years at the 2030 rate of 213  cans/year to complete the processing of 9.5 MT. So the 9.5 MT of Pu, under the most optimistic scenario, would not be removed until 2043 at the earliest. (Since only 1 MT was removed before 2020, that would still leave 1.0 MT at the site.) 

d. The limiting factor that DOE does not like to stress is that one-third of the stored Pu is in a metal form. This metal requires conversion to an oxide powder suitable for the dilution process. That metal to oxide conversion cost is never included in the cost estimates, and at the SRS CAB briefings that process has never been discussed. 

4. Any significant production rate increase is not expected until installation of three additional gloveboxes is completed in 2030 at the earliest (The Critical Decision to begin operations is not anticipated until FY 2030). 

Assuming the best case scenario of three new gloveboxes going operational in 2031 (decision to go operational expected in 2030), and an associated 3X increase in production, then ~500 cans per year would be processed per glovebox line at current rates. 

Only then will DOE/SRS be able to remove the 2800 cans remaining (under optimistic scenarios) by 2037. 

Conclusion: 

Without the new glovebox line, DOE will never make it by 2037. 
Since the 1997 DOE Record of Decision for long-term storage at SRS was for 50 years, removing it before 2047 would meet DOE’s goals, but not the Settlement Agreement mandate of 2037. 

DOE/NNSA is more likely to limp along at the current rate and then renegotiate the Settlement Agreement in the early 2030s than it is to spend $800 million to improve the removal rate of surplus Pu by 15-20 years; especially since the great uncertainties surrounding WIPP could delay the program even with the addition of the three glovebox lines. 

I hope this helps. I am perfectly willing to be corrected on these estimates, but only DOE/NNSA can do that. Please feel free to submit this to DOE/SRS. 

Thank you, 

Donald Moniak

Footnotes

(1) The decision to consolidate long-term storage of 11-15 MT metric tons of plutonium metals and oxide powders, also referred to as “non-pit” plutonium, at SRS was made in January 1997. The long-term storage period is “up to fifty years.”

Prior to consolidation, the condition of the plutonium had to meet what is known as the 3013 Standard, which “provides criteria for stabilization of plutonium-bearing materials at DOE facilities to safe and stable forms and packaging for storage with minimal surveillance for up to 50 years.” Efforts to meet this standard prior to shipment to SRS took place in the late 1990’s to early 2000’s at the now-closed Rocky Flats Plant in Colorado and the Hanford nuclear reservation in Washington State.

DOE intended to have the “cleanest” of these Pu materials converted to commercial nuclear fuel known as “Mixed Oxide Fuel,” or MOX.”

As a result of the stabilization and shipments, SRS currently has between ~4,300 to 5,000 containers known as “3013 cans;” referred to as such because they meet the requirements of DOE’s Standard 3013.

After the multi-billion dollar program to convert the materials to a commercial “Mixed Oxide” plutonium fuel fizzled in the the mid 2016’s, DOE turned to the “dilute and dispose” process.

Dilute and dispose involves “downblending” plutonium oxide powder with a mix of classified “adulterants” and other inert materials to create a new waste product containing about three percent plutonium. The waste product is then packaged and shipped to DOE’s Waste Isolation Pilot Plant (WIPP) in New Mexico, where it is buried in the nation’s only operational transuranic waste repository.

Two presentations made by SRNS managers to the SRS Citizens Advisory Board (CAB) in July 2023, describe the dilute and dispose program in general and improvement initiatives.

Additional information on the earlier history of the Surplus Pu Storage and Disposition program can be found is the two-part story, Plutonium is Not For Amateurs and Dr. Edward Lyman’s definitive work on the rise and fall of the MOX project, Excess Plutonium Disposition: The Failure of MOX and the Promise of Its Alternatives.

(2) The Nuclear Advisory Council meeting can be viewed by going to the South Carolina Legislature video archives, and scrolling down to the April 29th Nuclear Advisory Council meeting.

(3) A critique of the Plutonium Pit Production program was provided during the public comment period by Savannah River Site Director Tom Clements.