Saturday, May 10, 2014

The Truth About Nuclear Power - Part 15

Subtitle:  Nuclear Safety Compromised by Bending the Rules

This article begins the second theme of the Truth About Nuclear Power series, with the first theme being nuclear power is uneconomic, the second theme is nuclear power is
Universal sign for nuclear radiation
unsafe to operate.   There are many who will immediately say that nuclear power is safe, and point to various facts to support their position.   These next few articles will refute that argument and show that, not only are nuclear plants not safe, they grow more unsafe each year.  


For those who have not read the articles on nuclear power being uneconomic, please see this link. 

The approximately one dozen articles on nuclear safety will include (1) the relationship between plant operators and the regulatory commission, NRC, and show that safety regulations are routinely relaxed to allow the plants to continue operating without spending the funds to bring them into compliance.  (2) Also, the many, many near-misses each year in nuclear power plants will be discussed.   (3) The safety issues with short term, and long-term, storage of spent fuel will be a topic. (4)  Safety aspects of spent fuel reprocessing will be discussed.  (5) The health effects on people and other living things will be discussed.  The three major nuclear disasters (to date) will be discussed, (6)  Chernobyl, (7) Three Mile Island, and (8)  Fukushima.   (9) The near-disaster at San Onofre will be discussed, and (10) the looming disaster at St. Lucie.  (11)  The inherent unsafe characteristics of nuclear power plants required government shielding from liability, or subsidy, for the costs of a nuclear accident via the Price-Anderson Act.  (12) Finally, the serious public impacts of evacuation and relocation after a major incident, or "extraordinary nuclear occurrence" in the language used by the Price-Anderson Act, will be the topic of an article. 

Safety Rules are Bent

The NRC has been working with nuclear power plant owners to routinely weaken safety regulations, which allows the plants to continue operating, according to a 2011 investigation by AP (Associated Press).  see link   The plant owners argue that the safety regulations in question are overly-safe and unnecessary.  Yet, many of the relaxed regulations are alarming.   It is doubtful that the general public is aware of just how dangerous the plants are in the first place, and made even more unsafe by relaxing the regulations. 

From the AP investigation:  "Examples abound. When valves leaked, more leakage was allowed — up to 20 times the original limit. When rampant cracking caused radioactive leaks from steam generator tubing, an easier test of the tubes was devised, so plants could meet standards.


Failed cables. Busted seals. Broken nozzles, clogged screens, cracked concrete, dented containers, corroded metals and rusty underground pipes — all of these and thousands of other problems linked to aging were uncovered in the AP's yearlong investigation. And all of them could escalate dangers in the event of an accident."
The US plants were originally designed for only 40 years operation.  Safety margins were used that would allow the plants to run for 40 years, and a bit more as good engineering practice.  It is the "bit more" that is at issue.  One example is the brittleness of the reactor vessel.  That is rather an important item, as the reactor vessel contains the nuclear fuel, plus pressurized water at high temperature.  The AP report states the criterion for brittleness was relaxed not once, but twice. Brittle metal in reactor vessel walls are less likely to withstand periodic pressure surges, but instead will crack.   Additionally, some plants seek an operating extension beyond the original 40 years, which is a recipe for more frequent failures as the plants age well beyond their design life. 
Another quote: "One 2008 NRC report blamed 70 percent of potentially serious safety problems on "degraded conditions." Some involve human factors, but many stem from equipment wear, including cracked nozzles, loose paint, electrical problems, or offline cooling components."  A specific instance was burst steam generator tubes at Indian Point in 2000 that released radioactive steam into the air.  Another instance cited is cracked nozzles on the reactor vessel head at Davis-Besse. 
Finally, many pipes are corroded and leaking liquids into the environment.  Valves are also leaking, many at rates that are above the allowable limits.  
Conclusion
This, then, is the state of nuclear power plants in the US.  The equipment is old, has been run hard, often at 100 percent capacity or slightly more for years on end.  How does a plant run at greater than 100 percent capacity?  Some equipment gets replaced with larger equipment, in a procedure known as debottlenecking, then the remaining equipment runs at greater than its design of 100 percent.  Upsets occur, causing pressure variations or pressure surges.  Electrical equipment degrades over time, pipes corrode, valves leak, all of which are normal and expected as process plants age.  The fact is, the nuclear power plants are grinding down, quite literally in many cases.  The safety factor that was there, once, is no longer there.   Nuclear safety is compromised by bending the rules.  
Previous articles in the Truth About Nuclear Power series are found at the following links.  Additional articles will be linked as they are published. 














Roger E. Sowell, Esq. 
Marina del Rey, California






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