2015 - 07 - 31 Scoping Comments, Milt Carrigan

Milt Carrigan, supporter of Mothers for Peace, wrote Comments for the NRC meeting on Scoping for EIS, August 5, 2015

Nuclear Power Doesn’t Offer an Effective Means for Addressing Climate Change

Efforts by the nuclear industry and its government allies to promote atomic power as an “emissions-free” energy source, and therefore offers a means of addressing climate change are far from credible.  Nuclear power is very ineffective at addressing climate change. When the entire fuel chain is examined,  nuclear power is a net producer of greenhouse gases.  While it emits less CO2 than electricity from coal, adding enough nuclear power to make a meaningful reduction in greenhouse gas emissions would cost trillions of dollars, create tens of thousands of tons of lethal high-level radioactive waste, and contribute to further proliferation of nuclear weapons materials,

In November 2000, the world recognized nuclear power as a dirty, dangerous and unnecessary technology by refusing to give it greenhouse gas credits during the UN Climate Change talks in the Hague, the Netherlands. The world dealt nuclear power a further blow when a UN Sustainable Development Conference refused to label nuclear a sustainable technology in April 2001.   A Nuclear-Free, Carbon-Free contingent is planned as part of the massive climate march in Paris this December.

Diablo Canyon’s Contribution to Damaging the World’s Ecosystem (3 major issues)

Issue # 1:   Release of radioactive fission gases into the atmosphere

Release of radioactive fission gases (stripped from reactor cooling water to relieve build up of pressure) into the atmosphere, as well as periodic purges and venting of gases that have leaked into plant interiors, result in airborne gases contaminating not only the air but also soil and water.

Venting is the routine release into the atmosphere of radioactive gases that leak from fuel rods and radioactive gases released hourly from reactors’ condensers.  Purging is the planned active flushing into the atmosphere of radioactive gases to decrease intensely radioactive environment that maintenance workers enter.

Radioactive gases released: Iodine 131 (that which escapes filters); tritium (H3) with a radioactive life of 200 years and released continuously into sea as H30, taken up by plants and trees, partially incorporating into the ecosystem, and can by absorbed through skin, lungs or GI tract.  (Carbon 14 routinely released in discharged water as well as gaseous effluents, with a radioactive life of 114,000 years).

On March 19, 2013, a majority of the NRC’s five-member governing body voted for more analysis of the costs and benefits of installing filters on reactor venting systems. NRC Chairman Allison Macfarlane disagreed with her colleagues’ decision to delay, saying the filters would be “a valid and important safety improvement.”The measure has been under consideration as one of the U.S. responses to Japan’s Fukushima Daiichi nuclear accident in March 2011, during which significant amounts of radiation were released into the air.

The NRC’s expert staff had recommended moving forward with a mandate to install the vents, but the nuclear industry had been pushing the agency to do more research. The commission said Tuesday that it was directing its staff to explore several options for the rule rather than issue the requirement immediately. It said that the agency would finalize a rule regarding filters by March 2017.

Recommendation:  Install filters on reactor venting systems immediately to limit radioactive emissions

Issue # 2: excessive heating of sea water returned to ocean after once-through cooling, killing plant and animal life (including endangered species)

Marine life in all forms, from endangered manatees and sea turtles to essential microscopic organisms, is being harmed and killed by once-through cooling systems, used to remove waste heat at nuclear power stations. After cycling through the power generating station, the heated water is discharged at temperatures up to 25 degrees F hotter than the water into which it flows. For each unit of electrical energy generated, two units of heat energy are released into the environment.  Not only are marine animals "entrained" or "impinged" by the intake system, but billions of smaller marine organisms, essential to the food web, are also sucked into the reactor operating system and largely destroyed.  Smaller fish and other organisms may be entrained through the entire reactor system and are often scalded by the heated water before being discharged into the waterway. Others, pulverized by the reactor condenser system, emerge as sediment that clouds the water around the discharge area, often blocking light from the ocean floor. The resulting shadow effect kills plant and animal life around reactor discharge systems by curtailing the light and oxygen they need to survive.

Once-through cooling systems transfer the heat load to the intake water (2.5 billion gallons of sea water brought in daily by each of the plants’ two reactors) and discharges the heated water back into the environment, using the same body of water as a heat sink to absorb and dissipate the excess heat generated by the system. In contrast, operators using cooling towers draw in a lowered water intake of about 20,000 gallons a minute, reducing the potential for damage to marine life sucked into the nuclear plant.

Pacific Gas & Electric (PG&E), for many years, provided state water authorities with skewed data on its Diablo Canyon nuclear power station. The data showed that the plant's intake of billions of gallons of water a day did very little harm to surrounding marine life. PG&E's conclusions were based on the unscientific formula that the amount of sea life drawn into the system at the intake port could be accurately measured by the amount of small fish and other organisms at the outflow of the cooling system.

In the spring of 2000, Diablo Canyon's operators were discovered to have withheld information from environmental regulators for two decades revealing the true effect of the reactor's hot water discharges into the coastal waters off Diablo Cove and miles beyond. The concealed data included infrared images indicating more extensive thermal plume impact zones than previously admitted and time-series photographs showing the progressive deterioration of biologically important marine habitat in coastal waters around the reactor. The damage was catastrophic to the indigenous marine life community, including the near obliteration of the already threatened black and red abalone populations. The concealed findings also revealed up to a 90 percent destruction of many varieties of sea life as they passed through Diablo Canyon's cooling system. These findings had never been reported to state or federal agencies.

State water authorities viewed the escalating damage as sufficiently severe to press for a cease and desist order against the utility's previously accepted levels of waste heat discharges. A state cease and desist order would have effectively halted, or reduced the thermal discharges, or reduced their temperature, and imposed severe fines on the utility for continued heat pollution that threatened marine habitat and its indigenous species.

However, the order was undermined by the utility. Despite publicly documented evidence, and even evidence of its own, PG&E argued that no mitigation action was needed. Using a threat to outspend environmental regulators in legal actions appealing the cease and desist order, PG&E forced the authorities to back down. Instead, the state regulators have proposed to accept a settlement that ignores the reactor's ongoing thermal damage and includes a cash pay-off of just $4.5 million for vaguely worded marine species protection measures while simultaneously reducing the scope of monitoring the harmful effects of the Diablo Canyon cooling system.  This regulatory retreat in effect allows the utility to continue its business-as-usual practices while sacrificing an entire indigenous marine life community as the cost of marketing electricity.

Recommendationadd cooling towers to both reactors at Diablo Canyon to diminish harm to marine life, including destruction of endangered species by reducing the temperature of heated water discharged back into the cove.

Issue #3:  Generating 20-30 tons of high-level hot nuclear waste annually, cooled for at least 5 years in open air pools of water, then stored in thin, vulnerable dry casks.

In addition to residual uranium, the waste produced by the two reactors at Diablo Canyon NPP is about 1 % plutonium that is formed inside the fuel rods by the reactors. The waste also contains about 5 % highly radioactive fission products like cesium, strontium and iodine, making it millions of times more radioactive than “fresh” uranium fuel. Unshielded, it delivers a lethal dose in seconds and will remain a hazard for at least 12,000 human generations. High-level waste is piling up at reactor sites, stored outside of containment in pools, and in large dry containers called casks.

The Nuclear Regulatory Commission (NRC) has stated that the waste may need to be stored at current sites indefinitely. It has evaluated “storing spent fuel beyond the licensed operating life of reactors over three timeframes: 60 years [short-term = 120 years], 100 years after the short-term [220 years], or indefinitely.” Short-term assumes reactor operates for 40 years plus 20 year license extension: 40+20+60=120 years.

The dry storage canisters at most U.S. nuclear plants are only 1/2″ to 5/8″ thick stainless steel.  In other countries, such as Germany, 14″ to 20″ thick ductile cast iron canisters/casks are used, such as the CASTOR V/19.  The U.S. nuclear industry could have chosen the thick CASTOR sealed ductile cast iron casks (e.g., the V/21 approved by the NRC).  Instead, they use lower quality canisters, choosing profits over our safety. NRC documents provide data that indicate thin storage containers can fail 16 years after a crack initiates.

The NRC claims fuel must be reloaded into new canisters every 100 years, unless there is a permanent repository. However, they have no technical basis to state these canisters will last 100 years, but they do have data that indicates a much sooner potential failure rate.

None of the current U.S. thin steel storage canisters are adequately designed for over 20 year storage and may start failing in as little as 17 to 20 years with through-wall cracks. Vendor claims of longer storage times are not supported by data.  There is no aging management designed into these thin canisters. They cannot even be inspected for cracks or repaired.

Numerous factors can trigger stress corrosion cracks in these thin canisters.  Salt moist air is one that the NRC has studied more extensively than the others.  The nuclear waste containers used in the U.S. were not designed to last for more than 20 to 40 years.  However, NRC technical staff stated the stainless steel nuclear waste dry storage canisters used throughout the U.S. may crack within 30 years from stress corrosion cracking in marine environments (like that found at Diablo Canyon). And there is no current technology to inspect or repair these canisters for cracks and no current method to replace these canisters. Other stainless steel products can be inspected and repaired, but that technology cannot currently be used for canisters filled with nuclear fuel waste.

Crack initiation is an unknown variable, since the nuclear industry has not been inspecting installed dry storage canisters and has yet to develop a method to inspect them for cracks.  However, a 2014 inspection  found sea salt crystals on a Diablo Canyon canister that had only been loaded for two years.  Only two Diablo canisters were inspected, ranging from only 2 to 3.5 years in service with heat load of 15 to 20 kW at time of loading.    The canister loaded for only two years had sea salts and a low enough temperature range to trigger the corrosive environment needed for stress corrosion cracking initiation — much sooner than the NRC expected.

METAL CORROSION FROM COASTAL ENVIRONMENT: Nuclear waste storage near the coast could fail and release radiation due to the corrosive nature of salt air with metal.  Pitting corrosion in a salt fog environment is troubling. If a canister became sufficiently corroded, it would have to be replaced and the fuel assemblies moved. Further, the canister and fuel rods are pressurized, so leakage would be out of the canister. The NRC considers this a major issue, but doesn’t have solutions to offer.

DIABLO CANYON USES HOLTEC DRY CASKS. Reports of quality control issues from Holtec employees and NRC employees bring into question how reliable these casks will be over time.


Primary recommendation: On a tour of the Diablo Canyon Nuclear Power Plant in October 2013, sponsored by the Diablo Canyon Independent Safety Committee, I sat next to a senior member of the Committee who is a leading expert on nuclear reactor safety and probabilistic risk assessment of operating reactors. He has a stellar international reputation and has chaired an IAEA working group, as well as presented lectures at the Agency’s international conferences.  As our bus came within view of the Plant’s ghoulish dry cask cemetery for the living dead, he suddenly turned to me and said:

“We can’t build any more nuclear power plants until we know what to do with the waste.”

His directness and honest was in stark contrast to the PR speak I’d heard all morning.  Now, I’m of the opinion that not  building new plants isn’t enough; we must immediately stop producing more nuclear waste.

Second recommendation: all new dry casks added to the cemetery at Diablo Canyon be the thick CASTOR sealed ductile cast iron casks rather than thin storage containers that can fail 16 years after a crack initiates.