UCS Blog - All Things Nuclear (text only)

Tillerson, Mattis and the Chinese

Rex Tillerson and James Mattis are talking to their Chinese counterparts. The conversation is just getting started but it appears to be constructive. Their remarks to the press after a recent meeting in Washington with State Councilor Yang Jiechi and General Fang Fenghui should calm Asian fears about potentially destabilizing changes to US policy in the region.

US Secretary of State Rex Tillerson and US Secretary of State James Mattis meet with Chinese State Councillor Yang Jiechi and General Fang Fenghui, Chief of the General Staff of China’s People’s Liberation Army in Washington on 21 June 2017.

No Panic on North Korea

Mattis addressed concerns about North Korea’s nuclear program by reminding reporters that, “China’s end state on the Korean Peninsula in terms of nuclear weapons is the same as ours, and we continue to work towards that end state.”  Tillerson added that the United States and China “affirmed our strong commitment to cooperate, including through the UN, to realize our shared goal of denuclearization of the Korean Peninsula.”

China’s People’s Daily emphasized the need for “continued peace and stability” on the Korean penninsula and “resolving problems through negotiations.” It highlighted a proposal to reconstitute diplomatic talks around a “joint freeze” that would require the United States and its regional allies to stop regular military exercises in return for a halt in North Korean nuclear and missile tests.

Tillerson responded cooly to the “joint freeze” proposal, noting that the United States “will continue to take necessary measures to defend ourselves and our allies.”

Preserving Strategic Stability

The former Exxon executive reiterated his desire to focus on the long-term. He wants to use the new dialogues with China to redefine “how we’re going to engage and how we’re going to live with one another over the next 40 years.” Tillerson announced that “US and Chinese civilian and military teams” will “start discussions in new areas of strategic concern like space, cyberspace, nuclear forces, and nonproliferation issues.”

If those discussions do indeed take place it would represent a significant step forward in US and Chinese efforts to manage technologies both sides see as potent sources of military advantage that could undermine strategic stability.

The People’s Daily, which is owned and operated by the Chinese Communist Party, focused its description of the talks on the issues that could lead to a military conflict rather than the weapons that might be used after it starts. It reported that “the American side indicated the US government adheres to pursuing the one-China policy, that the United States recognizes Tibet is a part of China and that it does not support activities to divide or break up China.”

Neither Tillerson nor Mattis specifically mentioned Taiwan or Tibet, although Tillerson did resurrect  traditional US talking points on China’s on human rights record.

Thucydides Trappings

Politico reported that the Secretary of Defense, the National Security Adviser and other senior members of the Trump administration are turning to the ancient Greeks for guidance on US-China policy. Hopefully, the impetus is a desire to avoid war, but history buffs with a fixation on the rise and fall of nations can have other motivations. Mattis told the press that “while competition between our nations is bound to occur, conflict is not inevitable.” Steve Bannon, on the other hand, may believe that if the United States and China are destined for war, as Harvard’s Graham Allison suggests, history may hold the key to US victory.

Ancient wisdom is not always the best answer to contemporary problems. The marriage counselor who sends his patients to Plato’s Phaedrus to discover the true meaning of human love is less apt to be successful than the one who helps troubled couples talk through the arguments that drove them apart. Tillerson and Mattis may find it more helpful to review the unsettled history of the US government’s relationship with the Chinese Communist Party than to look for the true cause of human conflict in The History of the Peloponnesian War.

Productive leaders tend to be more interested in the promise of the future than the problems of the past.  A dialogue that begins with a frank airing of old grievances can be cathartic. Skilled negotiators can use it to help build trust, encourage compromise and facilitate cooperation. Tillerson’s focus on the next forty years of the US-China relationship is encouraging and unsurprisingly businesslike.

For now, at least, Asia can rest a little easier knowing the governments of the United States and China are willing and able to talk constructively.

The Case of the Missing Numbers

Good performance requires good long-term planning. For federal agencies like the National Nuclear Security Administration (NNSA), one of its important functions is preparing its part of the federal government’s annual budget request, which normally includes information on projected budget requirements for future years. This year, not so much.

This is important because the Congress, which has final say on what the government funds, needs to know which programs will require increased funding in the following years. Those numbers give Congress and the public a sense of priorities and long-term planning that informs the annual federal budget process.

For the NNSA, those long-term budget numbers are called the Future-Years Nuclear Security Program, or FYNSP (commonly pronounced  “fin-sip”), and they are so important that they are, in fact, required by Congress.  In a typical budget request, the budget numbers are simply listed as “Outyears” and they are provided both by location—each NNSA facility, including the three nuclear weapons labs—and for each program area and project.

I assume this isn’t why the budget numbers are missing . . .

However, for almost the entire FY 2018 request, the NNSA budget does not provide future year numbers. In particular, for the Weapons Activities programs (as we discussed in The Bad, the FY 2018 requests were substantially more than the Obama administration projected in their FYNSP) there are no such projections at all in this budget. For example, we don’t know how much the NNSA thinks the B61 life extension program will cost in FY 2019-FY2022. That is information that the Congress should have.

(To be fair to the NNSA, the Department of Defense, where the budgets are far, far larger, also did not include outyear budget projections.)

The NNSA FY2018 budget offers an explanation for why there are no outyear budget figures:

Estimates for the FY 2019 – FY 2023 base budget topline for the National Nuclear Security Administration reflect FY 2018 levels inflated by 2.1 percent annually. This outyear topline does not reflect a policy judgement. Instead, the Administration will make a policy judgement on amounts for the National Nuclear Security Administrations’ FY 2019 – FY 2023 topline in the FY 2019 Budget, in accordance with the National Security Strategy and Nuclear Posture Review that are currently under development.

So, the budget doesn’t have projections because the NNSA is awaiting the results of the Pentagon-led Nuclear Posture Review and the Congressionally-mandated National Security Strategy that the Trump administration is conducting.

Frankly, that explanation is not satisfactory. There is almost no chance that the Nuclear Posture Review will decide to abandon most of the programs designed to maintain and improve the weapons in the US nuclear arsenal. And significant changes to the programs that are already underway (updates to the B61, W88, and W76) are highly unlikely because such modifications would inevitably lead to delays that the Pentagon and the NNSA would not support. For example, as mentioned in “The Bad,” NNSA officials have said any delays would affect certification requirements for the B61.

The only exception is the life extension program for the W80, which is intended for use on the proposed new nuclear-armed cruise missile, the Long-Range Standoff weapon, or LRSO. Secretary of Defense Mattis has testified that he is not yet convinced of the case for the LRSO, so there is a possibility that the program could be cancelled. (And it should be.) But even so, the NNSA should be planning as if it will not be, as the adverse impact of cancellation is significantly less than the consequences of undertaking required budget work on a weapon that is later cancelled.

Obama’s First NNSA Budget

For comparison, the Obama administration faced a similar situation when it came to office in 2009. Like the Trump administration, the first budget request, for FY2010, was delivered to Congress later than normal, in May rather than February. The Obama administration was also, like the Trump administration, doing a Nuclear Posture Review and a National Security Strategy. There was also a change in the political party of the President, so one might expect more substantive changes in nuclear weapons policy than if there was continuity in the White House.

Despite those similarities, the Obama administration delivered a FY2010 budget request that included projections for future years. To be fair, the Obama budget also stated that the projections for Weapons Activities were “only a continuation of current capabilities, pending upcoming strategic nuclear policy decisions.” But the budget actually included additional money for a study of the B61 life extension program, along with further increases in later years.

Moreover, the status of Weapons Activities was dramatically different in 2010 than it is now. In 2010, the W76 was the only active life extension program, and it was already in full production. The B61 was still in study phase, and there was no other active work being done on weapons in the stockpile.

Now, in 2017, the NNSA is involved in four major warhead projects simultaneously, three of which are ramping up substantially. The idea that the NNSA is putting the planning efforts for future work on these programs essentially on hold for a year is troubling.

I suspect one important factor leading to the missing future year budgets is the lack of people in place to do the planning. The man in charge of the NNSA is Lt. Gen. Frank Klotz (Air Force, retired), who by all accounts has done an able job running the agency. He is a holdover from the Obama era, and he was not asked by the Trump team to stay on until the very last day of the Obama administration (which he dutifully did). But no other officials have been nominated for any slots, leaving key positions like the deputy administrator empty while other slots have officials serving only in an acting capacity.

Playing with numbers

One small thing flagged but not described in The Good is the level of increases the Trump administration claims for its NNSA budgets compared to the Obama team’s budgets. The Trump budget claims an 11% increase for the NNSA overall, and even higher increases in Weapons Activities—around 15%–where the work on nuclear weapons is funded.

But those increases are in comparison to the final FY2016 budget, not the FY2017 budget. Notably, the FY2018 request only lists the FY2017 numbers that were in place under the Continuing Resolution (CR) that operated for a good portion of the year.

But in fact Congress did pass a final appropriations bill, albeit very far into the 2017 fiscal year, and for the NNSA those numbers were significantly higher than under the CR. If you compare the Trump budget to those figures, the NNSA budget receives an increase of 7%, not 11%, and the budget increase for  Weapons Activities is 11%, not 15%.

Make no mistake, those are still substantial increases (though as mentioned in The Good they are not dramatically more than increases the Obama administration requested and got Congress to support).

But it’s troubling that the Trump budget was presented in a way that makes it look like it has increased NNSA funding more than it actually has. Who is the audience for this charade?

 

Nuclear Leaks: The Back Story the NRC Doesn’t Want You to Know about Palo Verde

As described in a recent All Things Nuclear commentary, one of two emergency diesel generators (EDGs) for the Unit 3 reactor at the Palo Verde Nuclear Generation Station in Arizona was severely damaged during a test run on December 15, 2016. The operating license issued by the Nuclear Regulatory Commission (NRC) allowed the reactor to continue running for up to 10 days with one EDG out of service. Because the extensive damage required far longer than 10 days to repair, the owner asked the NRC for permission to continue operating Unit 3 for up to 62 days with only one EDG available. The NRC approved that request.

Around May 18, 2017, I received an envelope in the mail containing internal NRC documents with the back story for this EDG saga. I submitted a request under the Freedom of Information Act (FOIA) for these materials, but the NRC informed me that they could not release the documents because the matter was still under review by the agency. I asked the NRC’s Office of Public Affairs for a rough estimate of when the agency would conclude its review and release the documents. I was told that their review of the safety issues raised in the documents wasn’t a priority for the NRC and they’d get to it when they got to it.

Well, nuclear safety is a priority for me at UCS. And since I already have the documents, I don’t need to wait for the NRC to get around to concluding its stonewalling— I mean “review”—of the issues.  Here is the back story the NRC does not want you to know about the busted EDG at Palo Verde.

Emergency Diesel Generator Safety Role

The NRC issued the operating license for Palo Verde Unit 3 on November 25, 1987. That initial operating license allowed Unit 3 to continue running for up to 72 hours with one of its two EDGs out of service. Called the “allowable outage time,” the 72 hours balanced the safety need to have a reliable backup power supply with the need to periodically test the EDGs and perform routine maintenance.

The EDGs are among the most important safety equipment at nuclear power plants like Palo Verde. The March 2011 accident at Fukushima Daiichi tragically demonstrated this vital role. A large earthquake knocked out the electrical power grid to which Fukushima Daiichi’s operating reactors were connected. Power was lost to the pumps providing cooling water to the reactor vessels, but the EDGs automatically started and took over this role. About 45 minutes later, a tsunami wave spawned by the earthquake inundated the site and flooded the rooms housing the EDGs. With both the normal and backup power supplies unavailable, workers could only supply makeup cooling water using battery-powered systems and portable generators. They fought a heroic but futile battle and all three reactors operating at the time suffered meltdowns.

More EDG Allowable Outage Time

On December 23, 2005, the owner of Palo Verde submitted a request to the NRC seeking to extend the allowable outage time for an EDG to be out of service to 10 days from 72 hours. Longer EDG allowable outage times were being sought by nuclear plant owners. Originally, nuclear power reactors shut down every year for refueling. The refueling outages provided ample time to conduct the routine testing and inspection tasks required for the EDGs. To boost electrical output (and hence revenue), owners transitioned to only refueling reactors every 18 or 24 months and to shorten the duration of the refueling outages. To facilitate the transitions, more and more testing and inspections previously performed during refueling outages were being conducted with the reactors operating. The argument supporting online maintenance was that while it adversely affected availability (i.e., an EDG was deliberately removed from service for testing and inspecting), the increased reliability (i.e., tests to confirm EDGs were operable were conducted every few weeks instead of spot checks every 18 to 24 months). The NRC approved the amendment to the operating licenses extending the EDG allowable outage times to 10 days on December 5, 2006.

More NRC/Industry Efforts on Allowable Outage Times

While the EDGs have important safety roles to play, they are not the only safety role players. The operating license for a nuclear power reactor covers dozens of components, each with its own allowable outage time. Around the time that longer EDG allowable outage times were sought and obtained at Palo Verde, the nuclear industry and the NRC were working on protocols to make proper decisions about allowable outage times for various safety components. On behalf of the nuclear industry, the Nuclear Energy Institute submitted guidance document NEI 06-09 to the NRC. On May 17, 2007, the NRC issued its safety evaluation report documenting its endorsement of NEI-06-09 along with its qualifications for that endorsement.

To create yet another acronym for no apparent reason, the nuclear industry and NRC conjured up Risk Informed Completion Time (RICT) to use in place of allowable outage time (AOT). The NRC explicitly endorsed a 30-day limit on RICTs (AOTs):

“The RICT is further limited to a deterministic maximum of 30 days (referred to as the backstop CT [completion time] from the time the TS [technical specification or operating license requirement] was first entered.”

The NRC explained why the 30-day maximum limit was necessary:

“The 30-day backstop CT assures that the TS equipment is not out of service for extended periods, and is a reasonable upper limit to permit repairs and restoration of equipment to an operable status.”

NEI 06-09 and the NRC’s safety evaluation applied to all components within a nuclear power reactor’s operating license. The 30-day backstop limit was the longest AOT (RICT) permitted. Shorter RICTs (AOTs) might apply for components with especially vital safety roles.

For example, the NRC established more limiting AOTs (RICTs) for the EDGs. In February 2002, the NRC issued Branch Technical Position 8-8, “Onsite (Emergency Diesel Generators) and Offsite Power Sources Allowed Outage Time Extensions.” This Branch Technical Position is part of the NRC’s Standard Review Plan for operating reactors. The Standard Review Plan helps plant owners meet NRC’s expectations and NRC reviewers and inspectors verify that expectations have been met. The Branch Technical Position is quite clear about the EDG allowable outage time limit:

“An EDG or offsite power AOT license amendment of more than 14 days should not be considered by the staff for review.” [underlining in original]

Exceptions and Precedent

Consistent with the “every rule has its exception” cliché, neither the 14-day EDG AOT in NRC Branch Technical Position 8-8 nor the 30-day backstop limit in the NRC’s safety evaluation for NEI 06-09 are considered hard and fast limits. Owners can, and do, request NRC’s permission for longer times under special circumstances.

The owner of the DC Cook nuclear plant in Michigan asked the NRC on May 28, 2015, for permission to operate the Unit 1 reactor for up to 65 days with one of its two EDGs out of service. The operating licensee for Unit 1 already allowed one EDG to be out of service for up to 14 days. During testing of an EDG on May 21, 2015, inadequate lubrication caused one of the bearings to be severely damaged. Repairs were estimated to require 56 days.

The NRC emailed the owner questions about the 65-day EDG AOT on May 28 and May 29. Among the questions asked by the NRC was how Unit 1 would respond to a design basis loss of coolant accident (LOCA) concurrent with a loss of offsite power (LOOP) and a single failure of the only EDG in service. The EDGs are designed to automatically start from the standby mode and deliver electricity to safety components within seconds. This rapid response is needed to ensure the reactor core is cooled should a broken pipe (i.e., LOCA) drain cooling water should electrical power to the makeup pumps not be available (i.e., LOOP). The single failure provision is an inherent element of the redundancy and defense-in-depth approach to nuclear safety.

The NRC did not approve the request for a 65-day EDG AOT for Cook Unit 1.

The NRC did not deny the request either.

On June 1, 2015, the owner formally withdrew its request for the 65-day EDG AOT and shut down the Unit 1 reactor. The Unit 1 reactor was restarted on July 29, 2015.

More on the Back Story

About 18 months after one of two EDGs for the Unit 1 reactor at DC Cook was severely damaged during a test run, one of two EDGs for the Unit 3 reactor at Palo Verde was severely damaged during a test run.

About 18 months after DC Cook’s owner requested permission from the NRC to continue running Unit 1 for up to 65 days with only one EDG in service, Palo Verde’s owner requested permission to continue running Unit 3 for up to 62 days.

About 18 months after the NRC staff asked DC Cook’s owner how Unit 1 would respond to a loss of coolant accident concurrent with a loss of offsite power and failure of the remaining EDG, the NRC staff merely assumed that a loss of coolant accident would not happen during the 62 days that Palo Verde Unit 3 ran with only one EDG in service. Enter the back story as reported by the Arizona Republic.

On December 23, 2016, and January 9, 2017, Differing Professional Opinions (DPOs) were initiated by member(s) of the NRC staff registering formal disagreement with NRC senior management’s plan to allow the 62-day EDG AOT for Palo Verde Unit 3. The initiator(s) checked a box on the DPO form to have the DPO case file be made publicly available (Fig. 1).

Fig. 1 (Source: United States Postal Service)

The DPO initiator(s) allege that the 62-day EDG AOT was approved by the NRC because the agency assumed that a loss of coolant accident simply would not happen. The DPO stated:

“The NRC and licensee ignored the loss of coolant accident (LOCA) consequence element. Longer outage times increase the vulnerability to a design basis accident involving a LOCA with the loss of offsite power (LOOP) event with a failure of Train A equipment.”

Palo Verde has two fully redundant sets of safety equipment, Trains A and B. The broken EDG provided electrical power (when unbroken) to Train B equipment. The 62-day EDG AOT was approved based on workers scurrying about to manually start combustible gas turbines and portable generators to provide electrical power that would otherwise be supplied by EDG 3B. The DPO stated:

“The Train B EDG auto starts and loads all safety equipment in 40 seconds. The manual actions take at least 20 minutes, if not significantly longer.”

Again, the rapid response is required to mitigate a loss of coolant accident that drains water from the reactor vessel. When water does not drain away, it takes time for the reactor core’s decay heat to warm up and boil away the reactor vessel’s water, justifying a slower response time.

The NRC staff considered a loss of coolant accident for the broken EDG at Cook but allegedly dismissed it at Palo Verde. Curious.

The DPO also disparaged the non-routine measures undertaken by the NRC to hide their deliberations from the public:

“The pre-submittal call occurred on a “non-recorded” [telephone] line. The NRC staff debated the merits of the call in a headquarters staff only discussion. Note that the Notice of Enforcement Discretion calls are done on recorded [telephone] lines.”

President Richard Nixon’s downfall occurred when it become known that tape recordings of his impeachable offenses existed. The NRC avoided this trap by deliberately not following their routine practice of recording the telephone discussions. Peachy!

Cognitive Dissonance or Unnatural Selection?

The NRC’s approval of the 62-day EDG AOT for Palo Verde Unit 3 is perplexing, at best.

In the amendment it issued January 4, 2017, approving the extension, the NRC wrote:

“Offsite power sources and one train of onsite power source would continue to be available for the scenario of a loss-of-coolant accident” while EDG 3B was out of service.

In other words, the NRC assumed that loss of offsite power (LOOP) and loss of coolant accident (LOCA) are separate events. The NRC assumed that if a LOCA occurred, electrical power from the offsite grid would enable safety equipment to refill the reactor vessel and prevent meltdown. And the NRC assumed that if a LOOP occurred, a LOCA would not drain water from the reactor vessel, giving workers time to find, deploy, and start up the portable equipment and prevent core overheating.

But in the amendment it issued December 5, 2006, establishing the 10-day EDG AOT, the NRC wrote:

“During plant operation with both EDGs operable, if a LOOP occurs, the ESF [engineered safeguards] electrical loads are automatically and sequentially loaded to the EDGs in sufficient time to provide for safe reactor shutdown or to mitigate the consequences of a design-basis accident (DBA) such as a loss-of-coolant accident (LOCA).”

In those words, the NRC assumed that LOOP and LOCA could occur concurrently in design basis space.

More importantly, page B 3.8.1-2 of the bases document dated May 12, 2016, for the Palo Verde operating licenses is quite explicit about the LOOP/LOCA relationship:

“In the event of a loss of preferred power, the ESF electrical loads are automatically connected to the DGs in sufficient time to provide for safe reactor shutdown and to mitigate the consequences of a Design Basis Accident (DBA) such as a loss of coolant accident (LOCA).”

In those words, the operating licenses issued the NRC assumed that LOOP and LOCA could occur concurrently in design basis space.

So, the NRC either experienced cognitive dissonance in having two opposing viewpoints on the same issue or made the unnatural selection of LOCA without LOOP.

Actions May Speak Louder Than Words, But Inaction Shouts Loudest

Check out this chronology:

  • December 15, 2016: EDG 3B for Palo Verde Unit 3 failed catastrophically during a test run
  • December 21, 2016: Owner requested 21-day EDG AOT
  • December 23 2016: NRC approved 21-day EDG AOT
  • December 23, 2016: DPO submitted opposing 21-day EDG AOT
  • December 30, 2016: Owner requested 62-day EDG AOT
  • January 4, 2017: NRC approved 62-day EDG AOT
  • January 9, 2017: DPO submitted opposing 62-day EDG AOT
  • February 6, 2017: NRC special inspection team arrived at Palo Verde to examine EDG’s failure cause
  • February 10, 2017: NRC special inspection team concluded its onsite examinations
  • April 10, 2017: NRC issued special inspection team report

The NRC jumped through hoops during the Christmas and New Year’s holidays to expeditiously approve a request to allow Unit 3 to continue generating revenue.

The NRC has not yet responded to two DPOs questioning the safety rationale behind the NRC’s approval.

If the NRC really and truly had a solid basis for letting Palo Verde Unit 3 run for so long with only one EDG, they have had plenty of time to address the issues raised in the DPOs. Way more than 62 days, in fact.

William Shakespeare wrote about something rotten in Denmark.

The bard never traveled to Rockville to visit the NRC’s headquarters. Had he done so, he might have discovered that rottenness is not confined to Denmark.

Oyster Creek Reactor: Bad Nuclear Vibrations

The Oyster Creek Nuclear Generating Station near Forked River, New Jersey is the oldest nuclear power plant operating in the United States. It began operating in 1969 around the time Neil Armstrong and Buzz Aldrin were hiking the lunar landscape.

Oyster Creek has a boiling water reactor (BWR) with a Mark I containment design, similar to the Unit 1 reactor at Fukushima Daiichi. Water entering the reactor vessel is heated to the boiling point by the energy released by the nuclear chain reaction within the core (see Figure 1). The steam flows through pipes from the reactor vessel to the turbines. The steam spins the turbines connected to the generator that produces electricity distributed by the offsite power grid. Steam discharged from the turbines flows into the condenser where it is cooled by water drawn from the Atlantic Ocean, or Barnegat Bay. The steam vapor is converted back into liquid form. Condensate and feedwater pumps supply the water collected in the condenser to the reactor vessel to repeat the cycle.

Fig. 1 (Source: Tennessee Valley Authority)

The turbine is actually a set of four turbines—one high pressure turbine (HPT) and three low pressure turbines (LPTs). The steam passes through the high pressure turbine and then enters the moisture separators. The moisture separators remove any water droplets that may have formed during the steam’s passage through the high pressure turbine. The steam leaving the moisture separators then flows in parallel through the three low pressure turbines.

The control system for the turbine uses the speed of the turbine shaft (normally 1,800 revolutions per minute) and the pressure of the steam entering the turbine (typically around 940 pounds per square inch) to regulate the position of control valves (CVs) in the steam pipes to the high pressure turbine. If the turbine speed drops or the inlet pressure rises, the control system opens the control valves a bit to bring these parameters back to their desired values. Conversely, if the turbine speed increases or the inlet pressure drops, the control system signals the control valves to close a tad to restore the proper conditions. It has been said that the turbine is slave to the reactor—if the reactor power level increases or decreases, the turbine control system automatically repositions the control valves to correspond to the changed steam flow rate.

The inlet pressure is monitored by Pressure Transmitters (PT) that send signals to the Electro-Hydraulic Control (EHC) system. The EHC system derives its name from the fact that it uses electrical inputs (e.g, inlet pressure, turbine speed, desired speed, desired inlet pressure, etc.) to regulate the oil pressure in the hydraulic system that positions the valves.

Fig. 2 (Source: Nuclear Regulatory Commission)

Bad Vibrations

In the early morning hours of November 20, 2016, the operators at Oyster Creek were conducting the quarterly test of the turbine control system. With the reactor at 95 percent power, the operator depressed a test pushbutton at 3:26 am per the procedure. The plant’s response was unexpected. The positions of the control valves and bypass valves began opening and closing small amounts causing the reactor pressure to fluctuate. Workers in the turbine building notified the control room operators that the linkages to the valves were vibrating. The operators began reducing the reactor power level in an attempt to stop the vibrations and pressure fluctuations.

The reactor automatically shut down at 3:42 pm from 92 percent power on high neutron flux in the reactor. Workers later found the linkage for control valve #2 had broken due to the vibrations and the linkage for control valve #4 had vibrated loose. The linkages are “mechanical arms” that enable the turbine control system to reposition the valves. The broken and loosened linkages impaired the ability of the control system to properly reposition the valves.

These mechanical malfunctions prevented the EHC system from properly controlling reactor pressure during the test and subsequent power reduction. The pressure inside the reactor vessel increased. In a BWR, reactor pressure increases collapse and shrink steam bubbles. Displacing steam void spaces with water increases the reactor power level. When atoms split to release energy, they also release neutrons. The neutrons can interact with other atoms to causing them to split. Water is much better than steam bubbles at slower down the neutrons to the range where the neutrons best interact with atoms. Put another way, the steam bubbles permit high energy neutrons to speed away from the fuel and get captured by non-fuel parts within the reactor vessel while the water better confines the neutrons to the fuel region.

The EHC system’s problem allowed the pressure inside the reactor vessel to increase. The higher pressure collapsed steam bubbles, increasing the reactor power level. As the reactor power level increased, more neutrons scurried about as more and more atoms split. The neutron monitoring system detected the increasing inventory of neutrons and initiated the automatic shut down of the reactor to avoid excessive power and fuel damage.

Workers attributed the vibrations to a design flaw. A component in the EHC system is specifically designed to dampen vibrations in the tubing providing hydraulic fluid to the linkages governing valve positions. But under certain conditions, depressing the test pushbutton creates a pressure pulse on that component. Instead of dampening the pressure piles, the component reacts in a way that causes the hydraulic system pressure to oscillate, creating the vibrations that damaged the linkages.

The component and damaged linkages were replaced. In addition, the test procedure was revised to avoid performing that specific portion of the test when the reactor is operating. In the future, that part of the turbine valve test will be performed during an outage.

Vibrations Re-Visited

It was not the first time that Oyster Creek was shut down due to problems performing this test. It wasn’t even the first time this decade.

On December 14, 2013, operators conducted the quarterly test of the turbine control system at 95 percent power. They encountered unanticipated valve responses and reactor pressure changes during the test. The operators manually shut down the reactor as reactor pressure rose towards the automatic shut down setpoint.

Improper assembly of components in the EHC system and vibrations that caused them to come apart resulted in control valves #2 and #3 closing. Their closure increased the pressure within the reactor pressure, leading the operators to manually shut down the reactor before it automatically scrammed.

The faulty parts were replaced.

Bad Vibrations at a Good Time

If every test was always successful, there would be little value derived by the testing program.

Similarly, if every test was seldom successful, there would be little value from the testing program.

Tests that occasionally are unsuccessful have value.

First, they reveal things that need to be fixed

Second, they provide insights on the reliability of the items being tested. (I suppose tests that always fail also yield insights about reliability, so I should qualify this statement to say they provide useful and meaningful insights about reliability.)

Third, they occur during a test rather than when needed to prevent or mitigate an accident. Accidents may reveal more insights than those revealed by test failures. But the cost per insight is a better deal with test failures.

Increase in Cancer Risk for Japanese Workers Accidentally Exposed to Plutonium

According to news reports, five workers were accidentally exposed to high levels of radiation at the Oarai nuclear research and development center in Tokai-mura, Japan on June 6th. The Japan Atomic Energy Agency, the operator of the facility, reported that five workers inhaled plutonium and americium that was released from a storage container that the workers had opened. The radioactive materials were contained in two plastic bags, but they had apparently ripped.

We wish to express our sympathy for the victims of this accident.

This incident is a reminder of the extremely hazardous nature of these materials, especially when they are inhaled, and illustrates why they require such stringent procedures when they are stored and processed.

According to the earliest reports, it was estimated that one worker had inhaled 22,000 becquerels (Bq) of plutonium-239, and 220 Bq of americium-241. (One becquerel of a radioactive substance undergoes one radioactive decay per second.) The others inhaled between 2,200 and 14,000 Bq of plutonium-239 and quantities of americium-241 similar to that of the first worker.

More recent reports have stated that the amount of plutonium inhaled by the most highly exposed worker is now estimated to be 360,000 Bq, and that the 22,000 Bq measurement in the lungs was made 10 hours after the event occurred. Apparently, the plutonium that remains in the body decreases rapidly during the first hours after exposure, as a fraction of the quantity initially inhaled is expelled through respiration. But there are large uncertainties.

The mass equivalent of 360,000 Bq of Pu-239 is about 150 micrograms. It is commonly heard that plutonium is so radiotoxic that inhaling only one microgram will cause cancer with essentially one hundred percent certainty. This is not far off the mark for certain isotopes of plutonium, like Pu-238, but Pu-239 decays more slowly, so it is less toxic per gram.  The actual level of harm also depends on a number of other factors. Estimating the health impacts of these exposures in the absence of more information is tricky, because those impacts depend on the exact composition of the radioactive materials, their chemical forms, and the sizes of the particles that were inhaled. Smaller particles become more deeply lodged in the lungs and are harder to clear by coughing. And more soluble compounds will dissolve more readily in the bloodstream and be transported from the lungs to other organs, resulting in exposure of more of the body to radiation. However, it is possible to make a rough estimate.

Using Department of Energy data, the inhalation of 360,000 Bq of Pu-239 would result in a whole-body radiation dose to an average adult over a 50-year period between 580 rem and nearly 4300 rem, depending on the solubility of the compounds inhaled. The material was most likely an oxide, which is relatively insoluble, corresponding to the lower bound of the estimate. But without further information on the material form, the best estimate would be around 1800 rem.

What is the health impact of such a dose? For isotopes such as plutonium-239 or americium-241, which emit relatively large, heavy charged particles known as alpha particles, there is a high likelihood that a dose of around 1000 rem will cause a fatal cancer. This is well below the radiation dose that the most highly exposed worker will receive over a 50-year period. This shows how costly a mistake can be when working with plutonium.

The workers are receiving chelation therapy to try to remove some plutonium from their bloodstream. However, the effectiveness of this therapy is limited at best, especially for insoluble forms, like oxides, that tend to be retained in the lungs.

The workers were exposed when they opened up an old storage can that held materials related to production of fuel from fast reactors. The plutonium facilities at Tokai-mura have been used to produce plutonium-uranium mixed-oxide (MOX) fuel for experimental test reactors, including the Joyo fast reactor, as well as the now-shutdown Monju fast reactor. Americium-241 was present as the result of the decay of the isotope plutonium-241.

I had the opportunity to tour some of these facilities about twenty years ago. MOX fuel fabrication at these facilities was primarily done in gloveboxes through manual means, and we were able to stand next to gloveboxes containing MOX pellets. The gloveboxes represented the only barrier between us and the plutonium they contained. In light of the incident this week, that is a sobering memory.

Palo Verde: Running Without a Backup Power Supply

The Arizona Public Service Company’s Palo Verde Generating Station about 60 miles west of Phoenix has three Combustion Engineering pressurized water reactors that began operating in the mid 1980s. In the early morning hours of Thursday, December 15, 2016, workers started one of two emergency diesel generators (EDGs) on the Unit 3 reactor for a routine test. The EDGs are the third tier of electrical power to emergency equipment for Unit 3.

When the unit is operating, the source of power is the electricity produced by the main generator (labeled A in Figure 1.) The electricity flows through the Main Transformer to the switchyard and offsite power grid and also flows through the Unit Auxiliary Transformer to in-plant equipment. If the unit is not operating, electrical power flows from the offsite power grid through the Startup Transformer (B) to in-plant equipment. When the main generator is offline and power from the offsite power grid is unavailable, the EDGs (C) step in to provide electrical power to a subset of in-plant equipment—the emergency equipment needed to protect the reactor core and minimize release of radioactivity to the environment. An additional backup power source exists at Palo Verde in the form of gas turbine generators (D) that can supply power to any of the three units.

Fig. 1 (Source: Arizona Public Service Company)

I toured the Palo Verde site on May 11, 2016. The tour included one of EDG rooms on Unit 2 as shown in Figure 2. Each unit at Palo Verde has two EDGs. The EDG being tested on December 15, 2016, was manufactured in 1981 and was a Cooper Bessemer 20-cylinder V-type turbocharged engine. The engine operated at 600 revolutions per minute with a rated output of 5,500,000 watts.

Fig. 2 (Source: Arizona Public Service Company)

Assuming one of the two EDGs for a unit fails and there are no additional equipment failures, the remaining EDG and the equipment powered by it are sufficient to mitigate any design basis accident (including a loss of coolant accident caused by a broken pipe connected to the reactor vessel) and protect workers and the public from excessive exposure to radiation. Figure 3 shows the major components powered by the Unit 3 EDGs—a High Pressure Safety Injection (HPSI) train, a Low Pressure Safety Injection (LPSI) train, a Containment Spray train, an Essential Cooling Water Pump, an Auxiliary Feedwater Pump, and so on.

Fig. 3 (Source: Arizona Public Service Company Individual Plant Examination)

Because the EDGs are normally in standby mode, the operating license for each unit requires that they be periodically tested to verify they remain ready to save the day should that need arise. At 3:02 am on December 15, 2016, workers started EDG 3B. Workers increased the loading on EDG 3B to about 2,700,000 watts, roughly half load, at 3:46 am per the test procedure.

Ten minutes later, alarms sounded and flashed in the Unit 3 Control Room alerting operators that EDG B had automatically stopped running to due low lube oil pressure. A worker in the area notified the control room operators about a large amount of smoke as well as oil on the floor of the EDG room. The operators contacted the onsite fire department which arrived in the EDG room at 4:06 am. There was no fire ongoing when they arrived, but they remained on scene for about 90 minutes to assist in the response to the event.

Operators declared an Alert, the third most serious in the NRC’s four emergency classifications, at 4:10 am due to a fire or explosion resulting in control room indication of degraded safety system performance. The emergency declaration was terminated at 6:36 am.

Seven weeks later after the fire had long been out, the oil on the floor long since wiped up, and all sharp-edged metal fragments long gone, and any toxic smoke long dissipated, the Nuclear Regulatory Commission (NRC) dispatched a special inspection team to investigate the event and its cause. The NRC dispatched its special inspection team more than a month after it authorized Unit 3 to continue operating for up to 62 days while its blown-up backup power source was repaired. The Unit 3 operating license originally allowed the reactor to operate for only 10 days with one of two EDGs out of service.

Workers at Palo Verde determined that EDG 3B failed because the connecting rod on cylinder 9R failed. It was the fifth time that an EDG of that type at a US nuclear power plant experienced a connecting rod failure and it was the second time that Cylinder 9R on EDG 3B at Palo Verde. It had also failed during a test in 1986.

Examinations in 2017 following the most recent failure traced its root cause back to the first failure. The forces resulting from that failure caused misalignment of the main engine crankshaft. (In this engine, the crankshaft rotates. The crankshaft causes the connecting rods to rise and fall with each rotation, in turn driving the pistons in and out of the cylinders.) The misalignment was very minor—the tolerances are on the order of thousands of an inch. But this minor misalignment over hundreds of hours of EDG operation over the ensuing three decades resulted in high cyclic fatigue failure of the connecting rod.

Workers installed a new crankshaft aligned within the tight tolerances established by the vendor. Workers also installed new connecting rods and repaired the crankcase. After testing the repairs, EDG B was returned to service.

NRC Sanctions

The NRC’s special inspection team did not identify any violations contributing to the cause of the EDG failure, in the response to the failure, or in the corrective actions undertaken to remedy the failure.

UCS Perspective

The NRC’s timeline for this event isn’t comforting.

The operating licenses issued by the NRC for the three reactors at Palo Verde allow each unit to continue running for up to 10 days when one of two EDGs is out of service. The Unit 3 EDG that was blown apart on December 15 could not be repaired within 10 days. So, the owner applied to the NRC for permission to operate Unit 3 for up to 21 days with only one EDG. But the EDG could not be repaired within 21 days. So, the owner applied to the NRC for permission to operate Unit 3 for up to 62 days with only one EDG.

The NRC approved both requests, the second on January 4, 2017. More than a month later, on February 6, 2017, the NRC special inspection team arrived onsite to examine what happened and why it happened.

Wouldn’t a prudent safety regulator have asked and answered those questions before allowing a reactor to continue operating for six times as permitted by its operating license?

Wouldn’t a prudent safety regulator have ensured the cause of EDG 3B blowing itself apart might not also cause EDG 3A to blow itself apart before allowing a reactor to continue operating for two months with a potential explosion in waiting?

Whether the answers are yes or no, could that prudent regulator please call the NRC and share some of that prudency? The NRC may be many things, but it’ll seldom be accused and never be convicted of excessive prudency.

Where’s a prudent regulator when America needs one?

The Ugly: Post #3 on the NNSA’s FY2018 Budget Request

On Tuesday, May 23, the Trump administration released its Fiscal Year 2018 (FY2018) budget request. I am doing a three-part analysis of the National Nuclear Security Administration’s budget. That agency, a part of the Department of Energy, is responsible for developing and maintaining US nuclear weapons. Previously we focused on The Good and The Bad, and today we have The Ugly.

The Ugly NNSA’s “New” Warhead a Sign of Things to Come?

The NNSA’s FY2018 budget request includes what might seem to be a relatively innocuous statement:

In February 2017, DOD and NNSA representatives agreed to use the term “IW1” rather than “W78/88-1 LEP” to reflect that IW1 replaces capability rather than extending the life of current stockpile systems.

In other words, rather than extending the life of the W78 and W88 warheads via a life extension program (or LEP), the NNSA will develop the IW1 to “replace” those warheads.

To my mind, that is an admission that the IW1—short for Interoperable Warhead One–is a new nuclear weapon, as UCS has been saying for quite some time.

The Obama administration was loath to admit as much, arguing that the proposed system—combining a primary based on one from an existing warhead and a secondary from another warhead—was not a “new” warhead. That reluctance stemmed from the administration’s declaration in its 2010 Nuclear Posture Review (NPR) that the United States would not develop new nuclear warheads or new military capabilities or new missions for nuclear weapons. Declaring the IW1 a new warhead would destroy that pledge.

That semantic sleight of hand by the Obama team was somewhat ugly: the IW1 is a new warhead. (For a lot more detail on the IW1 and the misguided “3+2 plan” of which it is part, see our report Bad Math on New Nuclear Weapons.)

However, what might be coming from the Trump administration is truly ugly.

The fact that the FY2018 NNSA budget admits the IW1 is a new warhead may be signal that the Trump team—which is doing its own NPR—will eliminate the Obama pledge not to develop new weapons or pursue new military capabilities and missions.

That change would send a clear message to the rest of the world that the United States believes it needs new types of nuclear weapons and new nuclear capabilities for its security. This would further damage the Nuclear Non-Proliferation Treaty (NPT), which is already fraying because the weapon states are not living up to their commitment to eliminate their nuclear weapons. Deep frustration on the part of the non-nuclear weapon states has led to the current negotiations on a treaty to ban nuclear weapons. New US weapons could also damage our efforts to halt North Korea’s nuclear program and undermine the agreement with Iran that has massively reduced their program to produce fissile materials for nuclear weapons.

Moreover, a likely corollary of withdrawing that pledge would be to pursue a new type of nuclear weapon, or a new capability. Some options have already been suggested:

  1. The Defense Science Board recommended developing weapons with “lower-yield, primary-only options” (because the B61 bomb and the air-launched cruise missile already have low-yield options, this was presumably for missile warheads, though the report does not specify).
  2. The author of the Obama NPR—Jim Miller—and Admiral Sandy Winnefeld (USN, retired) have proposed reviving the submarine-launched nuclear-armed cruise missile that was retired in the Obama NPR.

Those options are contrary to US security interests. Nuclear weapons are the only threat to the survival of the United States. Given that, and because there will not be a winner in a nuclear war, the US goal must be to reduce the role that these weapons play in security policy until they no longer are a threat to our survival. Continuing to invest in new types of nuclear weapons convinces the rest of the world that the United States will never give up its nuclear weapons, and encourages other nuclear-weapon states to respond in ways that will continue to threaten the United States.

Make no mistake, the United States already has incredibly powerful and reliable nuclear weapons that would deter any nuclear attack on it or its allies, and it will for the foreseeable future.

So the idea that the United States should pursue new types of weapons? That is truly ugly.

Upcoming GMD Missile Defense Test: Part 2

The upcoming missile defense test will also be the first intercept test of a new kill vehicle and will use an upgraded booster for the interceptor.

The GMD system currently has 36 deployed interceptors. A majority of the interceptors use a type of kill vehicle, the CE-I variant, that has had only two successful intercept tests in four tries. Its last successful intercept test was in 2008; the most recent test failed.

The other interceptors are equipped with the CE-II kill vehicle, which has had only a single successful intercept test in three tries. The Director of Operational Test and Evaluation’s 2014 report stated: “The reliability of the interceptors is low, and the [Missile Defense Agency (MDA)] continues discovering new failure modes during testing.”

The upcoming test will be the first intercept test of the new CE-II Block 1 kill vehicle. It uses newly designed divert thrusters meant to fix persistent problems guiding the kill vehicle. The divert thrusters are the small motors that make course adjustments when the kill vehicle is homing on its target. They make the fine adjustments in direction that make the difference between a hit and a miss.

The kill vehicle is the heart of the homeland missile defense system. Yet it has been dogged by a persistent problem called the track gate anomaly, which has appeared in tests for more than a decade, and which led to a failed intercept in 2010. The MDA has tried software and hardware fixes, essentially to compensate for vibrations caused by the rough combustion of the small divert motors. The CE-II Block 1 kill vehicle uses a new set of those motors to try to solve this problem. It was flight tested in January 2016, without complete success. In that case, one of the four motors stopped working and the kill vehicle flew off course—way off course.

The improved interceptor booster has upgraded avionics, and addresses obsolescence and reliability issues.

What if the test fails?

The MDA has been committed to increasing the number of interceptors to 44 before the end of 2017. To do so, it will be emplacing 10 new interceptors with CE-II Block 1 kill vehicles on them (eight CE-II Block 1 interceptors to complete the fleet and two to replace older interceptors equipped with the CE-I kill vehicle.) The MDA Director stated in testimony that he is waiting for the (presumably) successful intercept test before delivering these.

While that may seem an obvious criterion, that’s not the way GMD business has been done in the past. All (or nearly all) other currently-fielded GBI were fielded before they had completed a successful intercept test, as is shown in Fig. 1.

Fig. 1. This shows the number of deployed interceptors with the CE-I and CE-II kill vehicles (vertical axis) and the tests of those kill vehicles. (Source: “Shielded from Oversight”)

So, should this test fail, a consequence may be that the interceptor fielding would be put on hold until the test was repeated successfully. Because GMD tests take a significant amount of time to plan and organize, this is unlikely to happen quickly. For example, the January FTG-06 2010 intercept test failed and was repeated in December of that year.

Will political pressure to field these interceptors win out even if the test fails?

What if it’s a success?

Even if the test is successful, it is very important to look wholistically at the capabilities of the system and what has actually been demonstrated. While this test may demonstrate that the MDA is on the right track with the fixes to the kill vehicle, overall it is not even close to demonstrating that the system works in a real-world setting. The system has not yet been tested in the range of conditions under which it is expected to operate—for example, it hasn’t been successfully tested at night or against complex countermeasures that a determined adversary would surely try to include. The Pentagon’s Director for Operational Test and Evaluation assessment in 2014 is that the tests to date are “insufficient to demonstrate that an operationally useful defense capability exists.”

A successful test this week is the basis for better understanding the capabilities of the system, but it is not the basis for expanding the system.

Upcoming GMD Missile Defense Test: Part 1

Scheduled for later this week is the 18th intercept test of the Ground-based Midcourse Defense (GMD) system since 1999, and the 10th since the system was declared operational in 2004. What do we know about the test, and what’s riding on it?

The GMD system is, after more than 15 years on an accelerated deployment schedule and on order of $40 billion spent, still essentially an advanced prototype. It has serious reliability issues. In 9 of the 17 intercept tests since 1999, the kill vehicle failed to destroy the target. The test record has not been getting better over time as you would expect for a system that is maturing. And the tests have still not been done under realistic conditions.

The Missile Defense Agency (MDA) has said the upcoming test will be the first test against an ICBM-range target missile. Defending against long-range missile is, of course, what the whole system is about.

MDA classifies targets for the GMD system as intermediate range ballistic missiles (IRBM) (3,000-4,500 km) and intercontinental ballistic missiles (ICBM) (>5,500 km). This test will apparently use a three-stage ICBM-range target.

That leads to an important issue: what do we know about the target and how representative is it of what the US might face?

I was able to get the hazard zones for the test from the published Notices to Mariners for May 31-June 1, which are plotted in white in Google Earth. Figure 1 shows the zones where the stages will land from the launch of the target missile from Kwajalein and the interceptor from Vandenberg. These zones indicate the direction those missiles were launched. The large white region in the center is where debris from the intercept would land.

These zones allow us to determine that the target and interceptor will meet essentially head-on, and allow us to estimate the range of the target missile.

Fig. 1

A straight flight out of Kwajalein (thin white line in Fig. 2) would send the target north of the intercept zone, so the target missile apparently maneuvers during boost phase to follow the light blue line and make the collision with the GMD interceptor (yellow line) more head-on.

Fig. 2

The hard limit of the range of the target is about 5,800 km. If its range were any longer, it would land east of the hazard zone. So the target appears to be just slightly longer than the minimum range (5,500 km) considered to be an ICBM.

One important factor in a missile defense intercept is the closing speed of the engagement, how fast the distance between the target and interceptor disappears. This depends on the speeds of both the target and interceptor and the angle at which they approach. The angle of attack is significant: a head-on collision maximizes closing speed and a tail chase minimizes it.

Faster closing speeds give the interceptor less time to make course corrections, and are therefore more stressing for the interceptor. Table 1 shows the burnout speeds of missiles of various ranges on standard trajectories.

Table 1.

The conclusion I make from this is that the upcoming missile defense test is likely to be against an ICBM-range target that is marginally longer range than an IRBM, but significantly shorter range than missiles North Korea would need to target the United States. However, the closing velocity is likely to be larger than in many of the previous tests, which have been at significant crossing angles or with slower targets.

In Part 2 of this post, I look at what else is new in this test, and what the implications are.

Th Bad: Post #2 on the NNSA’s FY2018 Budget Request

On Tuesday, May 23, the Trump administration released its Fiscal Year 2018 (FY2018) budget request. I am doing a three-part analysis of the National Nuclear Security Administration’s budget. That agency, a part of the Department of Energy, is responsible for developing and maintaining US nuclear weapons. Yesterday we focused on The Good, today we have The Bad, and The Ugly is still to come.

The Bad Rising costs in warhead life extension programs

The NNSA’s most important task is to ensure that the weapons in the US nuclear arsenal are safe, secure and effective. As part of that work, the NNSA is simultaneously undertaking four different programs to extend the lives of four different warheads in the US stockpile: the W76 warhead deployed on submarines, the B61 bomb deployed on aircraft, the W88 warhead deployed on submarines and the W80 warhead for the proposed new air-launched cruise missile. The NNSA has not had such a confluence of work in decades.

That leads many observers to worry about how well the NNSA will manage such a heavy workload, especially when it is also trying to build one major new facility for uranium metal work and ramp up the new approach to dispose of excess plutonium.

Those concerns are only increased when a new president comes in talking about the need to “greatly strengthen and expand” the US nuclear capability. As described in The Good, this budget does not hint at any such effort.

Trump’s budget does, however, reveal rising costs for the existing warhead life extension programs initiated under the Obama administration. For the B61 and the W88, the Trump budget requests significantly more than what the Obama administration projected would be required for FY2018. For the B61, the Obama administration projected in the FY2017 budget that $728 million would be required in FY2018, an already large 15 percent increase above the FY2017 request. But the Trump administration’s request is $789 million, a 22 percent increase above FY2017. For the W88, a planned decrease of $30 million to $255 million (a 9 percent cut) became a $50 million–or 15 percent–increase, to $332 million.

The FY18 budget request offers relatively mundane explanations for these rising costs, including unexplained “increases.” They are particularly troubling, however, when considered in tandem with a recent Government Accountability Office (GAO) report on the life extension programs.

That report cites internal NNSA cost estimates showing the B61 will cost $10 billion, or $2.6 billion more than the NNSA currently predicts, and take an extra two years to produce the first new B61-12. Another internal NNSA estimate found that the W88 update could cost $1 billion more than previously expected. The GAO report also cites yet another internal NNSA estimate that the W80-4 warhead, being developed for the proposed new nuclear-armed cruise missile, may be underfunded by $1 billion, while a proposal to update the warhead’s secondary could add another $250-300 million to the total cost. That could bring the W88 program to over $10 billion as well.

Cost increases like that will mean increasing trouble for the NNSA. The “Weapons Activities” budget line, which funds all work on nuclear warheads, has already benefited from eight straight years of rising budgets averaging over 5% annually. The Trump budget seeks a 10% increase above the final level of funding Congress approved in the FY17 omnibus appropriations bill. If the numbers the GAO cites are correct, even larger increases will be needed in the future.

Another complicating factor is very tight timelines. The GAO notes the W80-4 is operating on an “accelerated, compressed schedule,” while officials have said the B61 may no longer meet certification requirements if there are any further delays producing new bombs. It looks more and more like the intersection of multiple warhead life extension programs, rising costs, and rushed production schedules could lead to a train wreck for NNSA.

And that is before the NNSA even starts work on its most far-reaching plan to develop a suite of new warheads to replace the existing ballistic missile warheads (but more on that in The Ugly).

Disappearing Dismantlement

In its final budget, the Obama administration proposed a modest increase in funding—from $52 million in FY2016 to $69 million in FY2017—for dismantling warheads that have been retired from the US nuclear stockpile. The result would be that the long line of weapons already in the queue for dismantlement would be taken apart more quickly, thus allowing the warheads retired under the New START agreement with Russia to be dismantled sooner as well.

Those in Congress who supported the Obama administration proposal pointed out that increasing dismantlement in the near term actually benefits life extension programs in the mid-term. Bringing on new employees and training them to dismantle warheads will help prepare them for the coming work on the B61 and the W88, which will entail dismantling the warheads, replacing aged components and reassembling them.

Led by the House Armed Services Committee, however, Congress ended up rejecting most of the increase, allowing only an additional $4 million in FY2017. For the House, anything proposed by the Obama administration that smacked of disarmament was too much, even if it was only taking apart weapons that have already been retired.

And now the Trump administration has dumped any thought of dismantling weapons sooner, noting in the FY18 budget that it is “eliminating the planned acceleration stated in the FY 2017 budget request.”

 

UCS in Science: The NRC Must Act to Reduce the Dangers of Spent Fuel Pool Fires at Nuclear Plants

In a Policy Forum article published in this week’s Science magazine, I argue, along with my co-authors Frank von Hippel and Michael Schoeppner, that the U.S. Nuclear Regulatory Commission (NRC) needs to take prompt action to reduce the alarmingly high potential for fires in spent fuel pools at U.S. nuclear plants.

The NRC allows nuclear plant owners to pack spent fuel into cooling pools at much higher densities than they were originally designed to handle. This has greatly increased the risk to the public should a large earthquake or terrorist attack breach the liner of a spent fuel pool, causing the pool to rapidly lose its cooling water. In such a scenario the spent fuel could heat up and catch fire within hours, releasing a large fraction of its highly radioactive contents. Since spent fuel pools are not enclosed in high-strength, leak-tight containment buildings, unlike the reactors themselves, much of this radioactive material could be readily discharged into the environment.

The consequences of a fire could be truly disastrous at densely packed pools, which typically contains much more cesium-137—a long-lived, extremely hazardous radioactive isotope—than is present in reactor cores. My Princeton University co-authors have calculated, using sophisticated computer models, that a spent fuel pool fire at the Peach Bottom nuclear plant in Pennsylvania could heavily contaminate over 30,000 square miles with long-lived radioactivity and require the long-term relocation of nearly 20 million people, for average weather conditions. Depending on the wind direction and other factors, the plume could reach anywhere from Maine to Georgia. My co-authors estimate the financial impact on the American economy of such contamination could reach $2 trillion: ten times the estimated $200 billion in damages caused by the release of radioactivity from the damaged Fukushima Daiichi plant.

The danger could be greatly reduced if plant owners thinned out the pools by transferring their older fuel to dry storage casks. But despite the relatively modest cost of this common-sense step—about $50 million per reactor—owners won’t do it voluntarily because they care more about their bottom line.

The NRC could require plant owners to expedite transfer of spent fuel to dry casks. But it refuses to do so, basing its decision on quantitative risk analyses that, as discussed in our Science article, underestimate the benefits of such a transfer by making numerous unrealistic and faulty assumptions. For example, its estimate of the economic damages of a fire in a densely packed spent fuel pool was $125 billion; nearly 20 times lower than the independent estimate of my Princeton co-authors.

In light of our findings, our article calls on the NRC to strengthen the technical basis of its risk analysis methodology by basing it on sound science and sensible policy judgments. We are confident that such an analysis will reveal that the substantial benefits of expedited transfer would more than justify the cost.

The Good, the Bad, and the Ugly: NNSA’s FY18 Budget Request

On Tuesday, May 23, the Trump administration released its Fiscal Year 2018 (FY2018) budget request. In an overall federal budget where many, many programs faced severe budget cuts, the National Nuclear Security Administration (NNSA) is on the receiving end of a proposed 11 percent budget increase (at least by the Trump administration’s accounting – more on that in a following post).

The NNSA is responsible for maintaining US nuclear weapons, controlling the spread of nuclear weapons, and producing, handling and disposing of fissile materials as needed.  Much of the agency’s increase is under “Weapons Activities” – the programs designed to maintain US nuclear weapons and related efforts – while funding for efforts to prevent the spread of nuclear weapons face budget cuts. That continues a trend that began in the Obama administration: more funding for weapons, less funding for nonproliferation.

In this post and the following two (The Bad and The Ugly), I take a closer look at NNSA’s budget. Let’s start with the good news.

The Good Ending MOX (Or Trying To, Again)

Perhaps the best news concerns the fate of the problematic “MOX” program to dispose of excess US plutonium. The Trump administration is wisely proposing to “terminate the MOX project and pursue the dilute & dispose (D&D) option as an alternative.” Under this project, excess plutonium, mostly from dismantled US nuclear weapons, would be turned into MOX—or “mixed oxide” nuclear fuel and burned in commercial US nuclear reactors. UCS has long opposed the MOX program because of its high cost and security risks.  Under the dilute and dispose option, the plutonium would instead be diluted with non-radioactive materials and disposed of in the Waste Isolation Pilot Plant (WIPP) in New Mexico, which is a geologic repository for military materials, including plutonium.

The Battle between Congress and the Obama Administration

The MOX fuel fabrication facility is in South Carolina, and the program only survives because of the support of state politicians who benefit from the program’s spending excesses.

For many years, Congress has provided enough funding to keep the MOX program alive, but not enough for major progress to be made on completing the enormous facility required to produce the plutonium-laced nuclear fuel.  Frustrated with the lack of progress, the Obama administration proposed in FY2015 to put the program on “cold standby,” halting construction while other options were considered. Congress refused to allow it, insisting that construction continue.

But Congress also again refused to provide sufficient funding to allow substantial progress in construction of the MOX plant. An independent study of the MOX program, requested by NNSA, found that if the level of funding Congress had been supporting—around $375 million annually—was all that could be provided, the MOX plant would not start operating until fiscal year 2100 and the life-cycle cost to finish the project would amount to a whopping $110.4 billion.

That study was part of a series of studies that all found the MOX program would cost far more than initially estimated, and take decades to complete. As a result, in FY2016 the Obama administration decided to cancel the MOX program outright, and to pursue the dilute and dispose option to get rid of the excess plutonium.

Unfortunately, largely because of the strong support for MOX from Senator Lindsey Graham (R-SC) and other members of the South Carolina delegation, Congress again refused to comply, and insisted on continued construction of the MOX plant to the tune of $340 million in FY2016.

The exact same pattern was repeated in FY2017, with Congress ultimately appropriating $335 million for construction of the MOX plant, rejecting the Obama administration’s decision to cancel the project.

Will Trump win the battle with Congress?

Now we will see if the Trump administration has better luck convincing Congress to do the right thing. The path it has chosen is identical to what the Obama administration proposed: cancel MOX and pursue dilute and dispose. It requested $270 million in the FY2018 budget to begin the process of shutting down the program.

A key factor will be the role of Sen. Graham, the most influential voice in support of the MOX program. He sits on the two committees – Appropriations and Armed Services – that have oversight of the program. Last year, according to sources, the Appropriations committee punted the issue to Armed Services, which agreed to cancel the program. That is, until Sen. Graham heard of the decision, and called his good friend Sen. John McCain (R-AZ), chair of the Armed Services Committee. The decision was reversed, and MOX lived another year.

But now it is the Trump administration canceling the program. Sen. Graham has never had a particularly good relationship with President Trump, nor does Sen. McCain. Will politics trump sanity again, or will we finally see the end of MOX?

No News is Good News

The other “good news” in the Trump administration’s NNSA budget request is the lack of anything particularly “new.” Despite rhetoric from President Trump that the United States needs to “greatly strengthen and expand its nuclear capability,” this budget request does not propose building additional warheads. It issues no call for new types of warheads, new military capabilities or new roles for nuclear weapons. And it makes no mention of resuming nuclear testing, something the United States wisely abandoned back in 1992, leading to an international moratorium on testing that only North Korea is violating. In most respects, this budget request simply continues the vision spelled out by the Obama administration in its final years in office (with some minor changes described in the upcoming piece, The Bad).

This does not mean, however, that significant changes are not possible in the future. The Trump administration is undertaking a comprehensive nuclear posture review, and military officials have testified that any major changes in US nuclear policy or posture—including a push for new weapons—will await the outcome of that study. Secretary of Defense Mattis ordered the effort to take no more than six months, which would allow any decisions to be incorporated into the Trump administration’s FY2019 request. That is where any new vision developed by President Trump and his team will come into play.

 

 

 

 

 

TVA’s Nuclear Allegators

The Nuclear Regulatory Commission (NRC) receives reports about potential safety problems from plant workers, the public, members of the news media, and elected officials. The NRC calls these potential safety problems allegations, making the sources allegators. In the five years between 2012 and 2016, the NRC received 450 to 600 allegations each year. The majority of the allegations involve the nuclear power reactors licensed by the NRC.

Fig. 1 (Source: Nuclear Regulatory Commission)

While the allegations received by the NRC about nuclear power reactors cover a wide range of issues, nearly half involve chilled work environments where workers don’t feel free to raise concerns and discrimination by management for having raised concerns.

Fig. 2 (Source: Nuclear Regulatory Commission)

In 2016, the NRC received more allegations about conditions at the Watts Bar nuclear plant in Tennessee than about any other facility in America. Watts Bar’s 31 allegations exceeded the allegations from the second highest site (the Sequoyah nuclear plant, also in Tennessee, at 17) and third highest site (the Palo Verde nuclear plant in Arizona, at 12) combined.  The Browns Ferry nuclear plant in Alabama and the Pilgrim nuclear plant in Massachusetts tied for fourth place with 10 allegations each. In other words, Watts Bar tops the list with a very comfortable margin.

Fig. 3 (Source: Nuclear Regulatory Commission)

In 2016, the NRC received double-digit numbers of allegations about five nuclear plants. Watts Bar, Sequoyah and Browns Ferry are owned and operated by the Tennessee Valley Authority (TVA). Why did three TVA nuclear plants place among the top five sources of allegations to the NRC?

Because TVA only operates three nuclear plants.

The NRC received zero allegations about ten nuclear plants during 2016. In the five year period between 2012 and 2016, the NRC only received a total of three allegations each about the Clinton nuclear plant in Illinois and the Three Mile Island Unit 1 reactor in Pennsylvania (the unit that didn’t melt down). By comparison, the NRC received 110 allegations about Watts Bar, 55 allegations about Sequoyah, and 58 allegations about Browns Ferry.

TVA President Bill Johnson told Chattanooga Time Free Press Business Editor Dave Flessner that TVA is working on its safety culture problems and “there should be no public concern about the safety of our nuclear plants.” The NRC received 30 of the 31 allegations last year from workers at Watts Bar, all 17 allegations last year from workers at Sequoyah, and all 10 allegations last year from workers at Browns Ferry.

So President Johnson is somewhat right— the public has no concerns about the safety of TVA’s nuclear plants. But when so many TVA nuclear plant workers have so many nuclear safety concerns, the public has every reason to be very, very concerned.

Nuclear plant workers are somewhat like canaries in coal mines. Each is likely to be the first to sense danger. And when nuclear canaries morph into nuclear allegators in such large numbers, that sense of ominous danger cannot be downplayed.

North Korea’s May 21 Missile Launch

A week after the test launch of an intermediate range Hwasong-12 missile, North Korea has tested a medium-range missile. From press reports, this appears to be a Pukguksong-2 missile, which is the land-based version of the submarine launched missile it is developing. This appears to be the second successful test of this version of the missile.

South Korean sources reported this test had a range of 500 km (300 miles) and reached altitude of 560 km (350 miles). If accurate, this trajectory is essentially the same as the previous test of the Pukguksong-2 in February (Fig. 1). Flown on a standard trajectory, this missile carrying the same payload would have a range of about 1,250 km (780 miles). If this test was conducted with a very light payload, as North Korea is believed to have done in past tests, the actual range with a warhead could be significantly shorter.

Fig. 1: The red curveis reportedly the trajectory followed on this test. The black curve (MET=minimum-energy trajectory) is the same missile on a maximum range trajectory.

The Pukgukgsong-2 uses solid fuel rather than liquid fuel like most of North Korea’s missiles. For military purposes, solid-fueled missiles have the advantage that they have the fuel loaded in them and can be launched quickly after moving them to the launch site. With large liquid-fuel  missiles you instead need to move them without fuel and then fuel them once they are in place at the launch site. That process can take an hour or so, and the truck carrying the missile must be accompanied by a number of trucks containing the fuel. So it is easier to spot a liquid missile before launch and there is more time available to attack it.

However, it is easier to build liquid missiles, so that is typically where countries begin. North Korea obtained liquid fuel technology from the Soviet Union in the 1980s, and built its program up from there. It is still in early stages of developing solid missiles.

Building large solid missiles is difficult. If you look at examples of other countries building long-range solid missiles, e.g., France and China, it took them several decades to get from the point of building a medium-range solid missile, like North Korea has, to building a solid ICBM. So this is not something that will happen soon, but with time North Korea will be able to do it.

Warhead Reentry: What Could North Korea Learn from its Recent Missile Test?

As North Korea continues its missile development, a key question is what it may have learned from its recent missile test that is relevant to building a reentry vehicle (RV) for a long-range missile.

The RV is a crucial part of a ballistic missile. A long-range missile accelerates its warhead to very high speed—16,000 mph—and sends it arcing through space high above the atmosphere. To reach the ground it must reenter the atmosphere. Atmospheric drag slows the RV and most of the kinetic energy it loses goes into heating the air around the RV, which then leads to intense heating of the surface of the RV. The RV absorbs some of the heat, which is conducted inside to where the warhead is sitting.

So the RV needs to be built to (1) withstand the intense heating at its outer surface, and (2) insulate the warhead from the absorbed heat that is conducted through the interior of the RV.

The first of these depends on the maximum heating rate at the surface and the length of time that significant heating takes place. Number (2) depends on the total amount of heat absorbed by the RV and the amount of time the heat has to travel from the surface of the RV to the warhead, which is roughly the time between when intense heating begins and when the warhead detonates.

I calculated these quantities for the two cases of interest here: the highly lofted trajectory that the recent North Korean missile followed and a 10,000 km missile on a normal (MET) trajectory. The table shows the results.

The maximum heating rate (q) is only about 10% higher for the 10,000 km range missile than the lofted missile. However, the total heat absorbed (Q) is nearly twice as large for the long-range missile and the duration of heating (τ) is more than two and a half times as long.

This shows that North Korea could get significant data from the recent test—assuming the RV was carrying appropriate sensors and sent that information back during flight, and/or that North Korea was able to recover the RV from the sea. But it also shows that this test does not give all the data you would like to have to understand how effective the heatshield might be before putting a nuclear warhead inside the RV and launching it on a long-range missile.

Some details

The rate of heat transfer per area (q) is roughly proportional to ρV3, where ρ is the atmospheric density and V is the velocity of the RV. Since longer range missiles reenter at higher speeds, the heating rate increases rapidly with missile range. The total heat absorbed (Q) is the integral of q over time during reentry.

This calculation assumes the ballistic coefficient (β) of the RV is 48 kN/m2 (1,000 lb/ft2). The heating values in the table roughly scale with β. A large value of β means less atmospheric drag so  the RV travels through the atmosphere at higher speed. That increases the accuracy of the missile but also increases the heating. The United States worked for many years to develop RVs with special coatings that allowed them to have high β and therefore high accuracy, but  could also withstand the heating under these conditions.

The results in the table can be understood by looking at how RVs on these two trajectories slow down as they reenter. Figs. 1 and 2 plot the speed of the RV versus time; the x and y axes of the two figures have the same scale. The maximum deceleration (slope of the curve) is roughly the same in the two cases, leading to roughly the same value of q. But the 10,000 km range missile loses more total energy—leading to a larger value of Q—and does so over a longer time than the lofted trajectory.

Ad Hoc Fire Protection at Nuclear Plants Not Good Enough

A fire at a nuclear reactor is serious business. There are many ways to trigger a nuclear accident leading to damage of the reactor core, which can result in the release of radiation. But according to a senior manager at the US Nuclear Regulatory Commission (NRC), for a typical nuclear reactor, roughly half the risk that the reactor core will be damaged is due to the risk of fire. In other words, the odds that a fire will cause an accident leading to core damage equals that from all other causes combined. And that risk estimate assumes the fire protection regulations are being met.

However, a dozen reactors are not in compliance with NRC fire regulations:

  • Prairie Island Units 1 and 2 in Minnesota
  • HB Robinson in South Carolina
  • Catawba Units 1 and 2 in South Carolina
  • McGuire Units 1 and 2 in North Carolina
  • Beaver Valley Units 1 and 2 in Pennsylvania
  • Davis-Besse in Ohio
  • Hatch Units 1 and 2 in Georgia

Instead, they are using “compensatory measures,” which are not defined or regulated by the NRC. While originally intended as interim measures while the reactor came into compliance with the regulations, some reactors have used these measures for decades rather than comply with the fire regulations.

The Union of Concerned Scientists and Beyond Nuclear petitioned the NRC on May 1, 2017, to amend its regulations to include requirements for compensatory measures used when fire protection regulations are violated.

Fire Risks

The dangers of fire at nuclear reactors were made obvious in March 1975 when a fire at the Browns Ferry nuclear plant disabled all the emergency core cooling systems on Unit 1 and most of those systems on Unit 2. Only heroic worker responses prevented one or both reactor cores from damage.

The NRC issued regulations in 1980 requiring electrical cables for a primary safety system to be separated from the cables for its backup, making it less likely that a single fire could disable multiple emergency systems.

Fig. 1 Fire burning insulation off cables installed in metal trays passing through a wall. (Source: Tennessee Valley Authority)

After discovering in the late 1990s that most operating reactors did not meet the 1980 regulations, the NRC issued alternative regulations in 2004. These regulations would permit electrical cables to be in close proximity as long as analysis showed the fire could be put out before it damaged both sets of cables. Owners had the option of complying with either the 1980 or 2014 regulations. But the dozen reactors listed above are still not in compliance with either set of regulations.

The NRC issued the 1980 and 2004 fire protection regulations following formal rulemaking processes that allowed plant owners to contest proposed measures they felt were too onerous and the public to contest measures considered too lax. These final rules defined the appropriate level of protection against fire hazards.

Rules Needed for “Compensatory Measures”

UCS and Beyond Nuclear petitioned the NRC to initiate a rulemaking process that will define the compensatory measures that can be substituted for compliance with the fire protection regulations.

The rule we seek will reduce confusion about proper compensatory measures. The most common compensatory measure is “fire watches”—human fire detectors who monitor for fires and report any sightings to the control room operators who then call out the onsite fire brigades.

For example, the owner of the Waterford nuclear plant in Louisiana deployed “continuous fire watches.” The NRC later found that they had secretly and creatively redefined “continuous fire watch” to be someone wandering by every 15 to 20 minutes. The NRC was not pleased by this move, but could not sanction the owner because there are no requirements for fire protection compensatory measures. Our petition seeks to fill that void.

The rule we seek will also restore public participation in nuclear safety decisions. The public had opportunities to legally challenge elements of the 1980 and 2004 fire protection regulations it felt to be insufficient. But because fire protection compensatory measures are governed only by an informal, cozy relationship between the NRC and plant owners, the public has been locked out of the process. Our petition seeks to rectify that situation.

The NRC is currently reviewing our submittal to determine whether it satisfies the criteria to be accepted as a petition for rulemaking. When it does, the NRC will publish the proposed rule in the Federal Register for public comment. Stay tuned—we’ll post another commentary when the NRC opens the public comment period so you can register your vote (hopefully in favor of formal requirements for fire protection compensatory measures.)

North Korea’s Missile in New Test Would Have 4,500 km Range

North Korea launched a missile in a test early in the morning of May 14, North Korean time. If the information that has been reported about the test are correct, the missile has considerably longer range than its current missiles.

Reports from Japan say that the missile fell into the Sea of Japan after traveling about 700 km (430 miles), after flying for about 30 minutes.

A missile with a range of 1,000 km (620 miles), such as the extended-range Scud, or Scud-ER, would only have a flight time of about 12 minutes if flown on a slightly lofted trajectory that traveled 700 km.

A 30-minute flight time would instead require a missile that was highly lofted, reaching an apogee of about 2,000 km (1,240 miles) while splashing down at a range of 700 km. If that same missile was flown on a standard trajectory, it would have a maximum range of about 4,500 km (2,800 km).

New press reports are in fact giving a 2,000 km apogee for the test.

Fig. 1  The black curve is the lofted trajectory flown on the test. The red curve is the same missile flown on a normal (MET) trajectory.

This range is considerably longer than the estimated range of the Musudan missile, which showed a range of about 3,000 km in a test last year. Guam is 3,400 km from North Korea. Reaching the US West Coast would require a missile with a range of more than 8,000 km. Hawaii is roughly 7,000 km from North Korea.

This missile may have been the new mobile missile seen in North Korea’s April 15 parade (Fig. 2).

Fig. 2 (Source: KCNA)

US-China Relations Set Up to Fail

US Secretary of State Rex Tillerson discusses US-China relations at a US Department of State assembly on 3 May 2017.

In June 1950 US President Harry Truman let North Korea set the course of US—China relations. Sixty-seven years later, with the Korean War still unresolved, President Trump is poised to make the same mistake.

The Road Not Taken

Just after North Korean forces invaded the south, Truman decided to protect the losing side in a Chinese civil war he believed was all but over. The defeated forces of the Republic of China (ROC) had abandoned their capital in Nanjing and fled to the island of Taiwan. The armies of the People’s Republic of China (PRC) were massing for an attack. Truman unequivocally rejected pleas for help from ROC President Chiang Kai-shek and his supporters in the US Congress. But the North Korean invasion changed his mind, and with it the course of modern Asian history.

Had Truman not linked the conflict in Korea to the Chinese civil war by placing the US 7th fleet between the Chinese mainland and Taiwan, the Chinese leadership may have felt less threatened by the US military intervention in Korea. Chinese forces may have continued to prepare to cross the Taiwan Straight instead of crossing the Yalu river. General McArthur might have defeated the north and unified the country. With no rival government in Taibei to occupy its seat at the United Nations, China may have been less inclined to lean towards Moscow or to develop nuclear weapons. And the rapprochement that began with President Nixon’s visit to China in 1972 might have started decades earlier.

It is impossible to know what might have been. But it may be useful to imagine how events in Asia might have unfolded if Harry Truman had not let Kim Il Sung alter US policy on China. It’s a thought experiment that could be especially helpful to the Trump administration, which is planning to hand Kim’s grandson another North Korean veto over improved US—China relations.

Trump’s China Policy Review

U.S. Secretary of State Rex Tillerson recently told a departmental assembly that the new administration was “immediately confronted with a serious situation in North Korea.” A review of US policy, completed with the assistance and support of Secretary of Defense James Mattis, determined the United States should “lean hard” on China’s leaders and “test their willingness to use their influence” to resolve the situation. More importantly, Tillerson and Mattis concluded this was “a good place to start our engagement with China.”

But making the North Korean nuclear weapons program a test case for US engagement with China is unlikely to end well. The US and Chinese governments both want a denuclearized Korean peninsula, but they have irreconcilable differences on how to achieve it. Dialing up the pressure to see if China’s leaders will yield is more likely to diminish the already low level of strategic trust between Washington and Beijing.

Divergent Views of the Korean Woods

The United States wants China to strangle the North Korean economy. China’s leaders don’t believe that will stop North Korea’s nuclear weapons program. It’s a conviction born from personal experience. The United States employed the same strategy against China in the 1950s and it didn’t work. Isolation and intimidation only strengthened China’s resolve to develop nuclear weapons. Chinese officials believe the Koreans will respond the same way.

Instead of creating an economic crisis, which heightens tensions, encourages risk-taking and could lead to war, Chinese leaders believe that North Korean economic stability is more likely to contribute to a peaceful resolution of the situation. They’ve agreed to UN sanctions targeting imports directly related to the development of nuclear and missile technology. But at the same time China has increased bilateral trade and economic aid. China’s leaders may be willing to impose short-term economic costs to signal displeasure, but imposing long-term restrictions designed to cripple North Korea’s economy would be a dramatic departure from current Chinese policy.

A Road to Failure

The new US Secretary of State and his counterpart at the Pentagon do not seem to recognize that there is a principled disagreement between China and the United States on North Korean policy. Tillerson and Mattis appear to interpret Chinese choices that are at odds with their own as evidence of incapacity, unwillingness or bad faith. So they’ve decided to “lean hard into China” to try to push its leaders to adopt and implement US policy preferences instead of their own.

Given the stakes for China, its leaders are likely to keep their own counsel. There is little reason for the Chinese to believe that President Trump and his advisors understand the North Koreans better than they do.

Tillerson told the assembly at State he hopes to set up the next half century of US-China relations. Tying the long-term future of the US—China relationship to a dramatic shift in Chinese policy on North Korea is a prescription for disappointment. Attempting to affect that shift through intimidation and brinkmanship is almost certain to fail.

Truman’s decision to link North Korean behavior to the US relationship with China created decades of misunderstanding and mistrust. Though times have changed and the issues are different the risks of giving North Korea undue influence over the long-term future of US—China relations remain, and deserve more careful consideration.

 

Exelon Generation Company (a.k.a. Nuclear Whiners)

The Unit 3 reactor at the Dresden Nuclear Power Station near Morris, Illinois is a boiling water reactor with a Mark I containment design that began operating in 1971. On June 27, 2016, operators manually started the high pressure coolant injection (HPCI) system for a test run required every quarter by the reactor’s operating license. Soon after starting HPCI, alarms sounded in the main control room. The operators shut down the HPCI system and dispatched equipment operators to the HPCI room in the reactor building to investigate the problem.

The equipment operators opened the HPCI room door and saw flames around the HPCI system’s auxiliary oil pump motor and the room filling with smoke. They reported the fire to the control room operators and used a portable extinguisher to put out the fire within three minutes.

Fig. 1 (Source: NRC)

What Broke?

The HPCI system is part of the emergency core cooling systems (ECCS) on boiling water reactors like Dresden Unit 3. The HPCI system is normally in standby mode when the reactor is operating. The HPCI system’s primary purpose is to provide makeup water to the reactor vessel in event that a small-diameter pump connected to the vessel breaks. The rupture of a small-diameter pipe allows cooling water to escape, but maintains the pressure within the reactor vessel too high for the many low pressure ECCS pumps to deliver makeup flow. The HPCI system takes steam produced by the reactor core’s decay heat to spin a turbine connected to a pump. The steam-driven pump transfers water from a large storage tank outside the reactor building into the reactor vessel. The HPCI system can also be used during transients without broken pipes. The HPCI system’s operation can be used by operators to help control the pressure inside the reactor vessel by drawing off the steam being produced by decay heat.

The HPCI auxiliary oil pump is powered by an electric motor. The auxiliary oil pump runs to provide lubricating oil to the HPCI system as the system starts and begins operating. Once the HPCI system is up and running, the auxiliary oil pump is no longer needed. At other boiling water reactors, the auxiliary oil pump is automatically turned off once the HPCI system is up and running—at Dresden, the auxiliary oil pump continues running.

Why the Failure was Reported

On August 25, 2016, Exelon Generation Company (hereafter Exelon) reported the HPCI system problem to the Nuclear Regulatory Commission (NRC). Exelon reported the problem “under 10 CFR 50.73(a)(20(v)(D), ‘Any event or condition that could have prevented the fulfillment of the safety function of structures or systems that are needed to mitigate the consequences of an accident.’”

Why It Broke

Exelon additionally informed the NRC that the HPCI system auxiliary oil pump motor caught fire due to “inadequate control of critical parameters when installing a DC shunt wound motor.” The HPCI system auxiliary oil pump motor had failed in March 2015 during planned maintenance. The failure in 2015 was attributed by Exelon to “inadequate cleaning and inspection of the motor” which allowed carbon dust to accumulate inside the motor.

How the NRC Assessed the Failure

The NRC issued an inspection report on December 5, 2016, with a preliminary white finding for the HPCI system problem. The NRC determined that the repair of HPCI system auxiliary oil pump motor following its failure in March 2015 resulted in the motor receiving higher electrical current than needed for the motor to run. Consequently, when the HPCI system was tested in June 2016, the high electrical current flowing to the auxiliary oil pump motor caused its windings to overheat and catch fire. The NRC determined that the inadequate repair in March 2015 caused the failure in June 2016. The NRC proposed a white finding in its green, white, yellow, and red string of increasing significant findings and gave Exelon ten days to contest that classification.

During a telephone call between the NRC staff and Exelon representatives on December 15, 2016, Exelon “did not contest the characterization of the risk significance of this finding” and declined the option “to discuss this issue in a Regulatory Conference or to provide a written response.” With the proposed white finding seemingly uncontested, the NRC issued the final white finding on February 27, 2017.

Why the NRC Reassessed the Failure

It took the NRC over two months to finalize an uncontested preliminary finding because Exelon essentially contested the preliminary finding, but not in the way used by the rest of the industry and consistent with the NRC’s longstanding procedures over the 17 years that the agency’s Reactor Oversight Process has been in place.

Instead, Exelon mailed a letter dated January 12, 2017, to the NRC requesting that the agency improve the computer models it uses to determine the significance of events.  Exelon whined that NRC’s computer model over-estimated the real risk because it considered only the failure of a standby component to start and the failure causing a running component to stop. Exelon pointed out that the auxiliary oil pump did permit the HPCI system to successfully start during the June 2016 test run and it later catching on fire did not disable the HPCI system. Exelon whined that the NRC’s modeling was “analogous to the situation where the starter motor of a car breaks down after the car is running and then concluding that ‘the car won’t run’ even though it is already running.”

The NRC carefully considered each of Exelon’s whines in its January 12 letter and still concluded that the failure warranted a white finding. So, the agency issued a white finding. With respect to Exelon’s whine that the auxiliary oil pump burned up after the HPCI system was up and running, the NRC reminded the company that the operators shut down the HPCI system in response to the alarms—had it been necessary to restart the HPCI system, the toasted auxiliary oil pump would have prevented it. It is not uncommon for the HPCI system to be automatically shut down (e.g., due to high water level in the reactor vessel) or to be manually shut down (e.g., due to operators restoring the vessel water level to within the prescribed band or responding to a fire alarm in the HPCI room) only to be restarted later during the transient. The NRC’s review determined that their computer model’s treatment of a “failure to restart” would yield results very similar to its treatment of a “failure to start.”

The auxiliary oil pump’s impairment reduced the HPCI system to one and done use. In an actual emergency, one and done might not have cut it—thus, NRC issued the white finding for Exelon’s poor performance that let the auxiliary oil pump literally go up in smoke.

The NRC conducted a public meeting on May 2, 2017, in response to Exelon’s letter. I called into the meeting to see if Exelon’s whines are as shallow and ill-conceived as they appear in print. I admit to being surprised—their whining came across even shallower live than in writing. And I would have bet it impossible after reading, and re-reading, their whiny letter.

What’s With the Whining?

Does Exelon hire whiners, or does the company train people to become whiners?

It’s a moot point because Exelon should stop whining and start performing.

Exelon whined that the NRC failed to recognize or appreciate that the auxiliary oil pump is only needed during startup of the HPCI system. During the June 2016 test run, the HPCI system successfully started and achieved steady-state running before the auxiliary oil pump caught fire. Workers put out the fire before it disabled the HPCI pump. But the NRC’s justification for the final white characterization of the “uncontested” finding explained why those considerations did not change their conclusion. While the auxiliary oil pump did not catch fire until after the HPCI system was successfully started during the June 2016 test run, its becoming toast would have prevented a second start.

Exelon expended considerable effort contesting and re-contesting the “uncontested” white finding. Had Exelon expended a fraction of that effort properly cleaning and inspection the auxiliary oil pump motor, the motor would not have failed in March 2015. Had Exelon expended a fraction of that effort properly setting control parameters when the failed motor was replaced in March 2015, it would not have caught on fire in June 2016. If the motor had not caught on fire in June 2016, the NRC would not even have reached for its box of crayons in December 2016. If the NRC had not reached for its box of crayons, Exelon would not have been whining in January and May 2017 that the green crayon instead of the white one should have been picked.

So, Exelon would be better off if it stopped whining and started performing. And the people living around Exelon’s nuclear plants would be better off, too.

US Needs More Options than Yucca Mountain for Nuclear Waste

On Wednesday, I testified at a hearing of the Environment Subcommittee of the House Energy and Commerce Committee. The hearing focused on the discussion draft of a bill entitled “The Nuclear Waste Policy Amendments Act of 2017.”

Yucca Mountain (Source: White House)

The draft bill’s primary objective is to revive the program to build a geologic repository at the Yucca Mountain site in Nevada for spent nuclear fuel and other high-level radioactive wastes. The Obama administration cancelled the program in 2009, calling it “unworkable,” and the state of Nevada is bitterly opposed to it, but Yucca Mountain still has devoted advocates in Congress, including the chairman of the subcommittee, John Shimkus (R-IL).

UCS supports the need for a geologic repository for nuclear waste in the United States but doesn’t have a position on the suitability of the Yucca Mountain site. We don’t have the scientific expertise needed to make that judgement.

However, in my testimony, I expressed several concerns about the draft bill, including its focus on locating a repository only at Yucca Mountain and its proposal to weaken the NRC’s review standards for changes to repository design.

UCS believes that rigorous science must underlie the choice of any geologic repository, and that the US needs options in addition to Yucca Mountain, which has many unresolved safety issues. In addition, we believe that any legislation that revises the Nuclear Waste Policy Act must be comprehensive and include measures to enhance the safety and security of spent fuel at reactor sites—where it will be for at least several more decades. For example, we think it is essential to speed up the transfer of spent fuel from pools to dry storage casks.

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