Thursday, June 30, 2011

So… we should dig up a lot of coal?

(Adapted from an Article in the Colorado Mountain Club's Quarterly: 
"Trails and Timberline" )
I was at my daughter’s homecoming parade at Colorado State University in Fort Collins and an excited gentleman came up to me asking if I would sign his petition to:


So I asked him: “Does this mean you think we should dig up a lot of Coal?” He seemed startled by my question – but did not answer. He only more frantically urged me to sign his petition “…for the sake of your children and your grandchildren!!” I guess the implication being: if I didn’t sign his petition, I don’t care about my children or grandchildren?

This encounter is a good example of the type of risk communication coming from some in the environmental movement. There is an intent to “stop something” based upon some group’s assertion of serious environmental hazard – but without any critical examination of the accuracy of the claims. Anybody challenging the accuracy of statements coming from groups trying to “stop the hazard” - are labeled as “unconcerned about the environment”. As a Colorado Mountain Club member who also just happens to be a nuclear engineer, I am taking this opportunity time to shed some light on the subject of “radiation hazards”. Eliminating uranium mining will not reduce public risk from radioactive materials exposure. Quite the contrary: it would just shift the radiation sources and likely increase it.

First, if we really did stop uranium mining – what would be the outcome of this? Answer: The US would end up needing to burn a lot more coal. Uranium has only one major current use: fueling nuclear power plants – which have been displacing the burning of fossil fuels for generating electricity since the 1960’s.
Is burning more coal really a better choice for the environment? I suppose that depends on one’s point of view about the linkage between excess CO2 buildup in the atmosphere and global warming, and whether we should be adding more CO2 when other sources of electricity are available that do not add any CO2. The public in Colorado seems to accept burning of coal for electricity because it is already here and has been used in our state for many years. I certainly do not think we should be forcing the our coal burning power plants to shut down – but I also think we should be switching over to power sources that do not add even more CO2 to the atmosphere.

Where Does the US Electricity Currently Come From?
From 2009 data: 44.5% of US electricity is generated by burning coal. 23.3% comes from burning natural gas, and 20.2% comes from nuclear power plants that use uranium - like the fellow in Fort Collins thinks we should stop mining. Our local supplier of electricity has a mix of energy sources not unlike the national average.

When you add up the numbers: 69.1% of our current electricity production involves producing CO2 emissions.

How did we get such a mix of energy sources for electricity? This question involves balancing resource availability, costs, and what current environmental policies allow.

It is not likely that there will be construction of new major hydroelectric dams as was done in the 1930’s. Hydroelectric dams which generate no CO2 emissions currently supply 10.4% of the country’s electricity. But, no more large hydroelectric sites are available and it is highly unlikely new major dam sites could be approved – primarily due to environmental impacts. Costs and permitting tend to dictate the rest for the electricity production choices. The figure on the next page shows how total electricity production costs (sum of construction, maintenance, and fuel costs) have averaged over the last ten years and why new large scale electricity production, by choice, would be either: coal or nuclear. Electricity production from natural gas and oil has been subject to very significant price fluctuations – because the fuel costs have been so volatile. Electric production costs for coal and nuclear plants are not as sensitive to fuel costs.

Why Not Renewable Energy – With No Fuel Costs?
Any discussion of electrical energy alternatives and environmental impact inevitably leads to the question: Why aren’t our electric utilities just jumping at the opportunity to install all kinds of renewable energy sources for electricity? After all, the fuel charges would theoretically be “Zero, right? The answer is: that while sources such as wind power and solar are obviously available – the only way to deploy them in significantly large quantities to displace burning of fossil fuels would be: if they could produce electricity that exactly matches the needs of the electrical grid at a given time of day. Unfortunately they don’t.

Wind power and solar can produce electricity – but their output goes up and down daily according to the patterns of Mother Nature and they require either some means of energy storage or a mechanism to back up their output when they are unavailable. As an example of this: the power output of a wind turbine varies as: (wind-speed)3. Thus: a unit that generates 4,000 kW at 20 M.P.H. would drop in output by 87% to 500 kW, if the wind-speed decreased down to 10 M.P.H. Now imagine trying to run several hundred such units and properly balance demand with wind turbine output so that a utility company customer’s computers and homeowner’s TV sets don’t fail due to power fluctuations. One option to get around this is to use wind turbines to pump large quantities of water uphill to large mountain reservoirs[1] and then let it out using a hydroelectric dam to make electricity as needed. But the reality is: people in Colorado do not seem any more interested in creating new large artificial water reservoirs up in the mountains for power production[2] pretty much for the same reasons they don’t want more hydroelectric dams.

In places like northern Germany and Denmark[3] which have large off-shore wind farms but no nearby mountain pumped storage reservoirs: oil and gas fired power plants actually end up being used to make up the difference. They basically stand-by, continue to burn fuel at minimal power output to be able to rapidly pick up the required power production if the wind speed is either too low – or too high (which requires the wind turbine to shut down to avoid failure). Thus, what you find is that “free wind power” in Denmark actually comes with the hidden support requirement of burning fossil fuels in order to be deployed in large quantities.

The other reason wind power is not being deployed that rapidly as originally hoped, is that people have started to realize that large wind power facilities necessitate deployment of many machines over vast areas of mountain ridges and seacoasts. Objection to wind power due to “visual impacts” is now actually a common problem that electric utilities have to deal with. There is not any public health risk from this, but people who spend several million dollars for beach front cottages tend to dislike anything spoiling their view. The photograph below is an artist’s conception of how a large offshore wind turbine farm would look from the seacoast off Cape Cod Massachusetts.

Photo Courtesy of Cape Wind Energy

Backing Ourselves into a Corner?

What I am trying to demonstrate is that some form of environmental opposition has been developed for just about every conceivable type of electricity production imaginable, and the source of such opposition is not always about protecting the public health and safety, or the environment. It frequently is related to one small group trying to protect their “immediate environment”. Some call this the: “Not in My Backyard” or “NIMBY” movement. The NIMBY movement may have legitimate real estate investment and personal property value concerns, but these should not be misconstrued as related to public health and safety, or protection of the environment concerns. That would be a real “smoke screen”.

Getting back to uranium mining: If we really had a campaign that stopped uranium mining, and:
·         There are no more viable hydroelectric sites.
·         Deploying large quantities of wind or solar energy for bulk electricity generation require back-up facilities that are either expensive or have major land-use implications.
·         Oil and gas burning are currently too expensive to consider.
What we are really doing is backing ourselves into a corner leaving us few options but: to dig up, transport, and burn a lot more coal.  After all, this is an accepted, although obviously dirty, way of making electricity. I am now going to talk about the radiation exposure hazards of burning coal.

Photo of a Coal Car staging area in the CSX Railway Yard in Virginia. Think about the last time you hiked or ski toured near Moffat Tunnel which runs from the foothills through the Front Range to Winter Park and  – you probably saw a lot more coal cars passing through than Ski Trains going to Winter Park.

45,500-ton Krupp Earth-mover, mines 76,455 cubic meters coal per day in Germany. German environmental groups are quick to criticize the US for not signing on to the Kyoto Protocol, yet Germany remains one of the world’s largest users of Coal.

If we seriously considered stopping uranium mining, how much coal would we need to replace it? Doing the math based upon 1,000,000 kW of electrical capacity it comes out roughly as follows based upon numbers from the US Government’s Council on Environmental Quality (CEQ) and the World Nuclear Association (WNA):

So, there’s also ‘Radioactive Stuff’ in Coal?
Yes. Uranium, thorium, radon, and radium are all naturally occurring radioactive elements that have been present in the earth’s environment since the dawn of time. These elements are readily found in the rock (granite, gneiss, meta-sedimentary rocks, and limestone) that is all around us, and in coal deposits like we burn for making electricity. The US Geological Survey[4] notes that, on average, coal from the Illinois Basin and Colorado Plateau contains ~4 parts per million (ppm) natural uranium and thorium[5]. Concentrations of 20 ppm are rare in the US, but actually common in China[6]. Fly ash, the residue from burning coal, however, tends to concentrate the natural radioactive elements resulting in concentrations of: 8-20 ppm. Is such background radiation dangerous to us? One of my old college textbooks on radiation protection[7] answered it this way:

All life, including man, has been exposed throughout its period of existence to natural sources of ionizing radiation. At the present time it has not been established whether exposure at the relatively low dose rate of average background radiation is harmful or whether, in fact, it is beneficial to man.”

Obviously all life on earth seems to co-exist with the existing natural levels of background radiation in our environment – but obviously I don’t advocate adding a lot more.

In Colorado we are naturally exposed to the highest background levels of radiation of almost anywhere in the US – but it isn’t caused by uranium mining activities. It’s primarily the rock and soil giving off various forms of radon gas. Approximately 55% of our radiation exposure is due to radon. The figure on the next page shows the EPA’s radon hazard map of the entire state.

On top of this are cosmic radiations (which depend on geographical latitude).

Above Figure taken from: United Nations Scientific Committee on Effects of Atomic Radiations, 2000 Edition, Annex B, p.87.

Figure: Courtesy of the Environmental Protection Agency Office of Radiation Programs

Our other major sources include: the rock we frequently hike or climb on (which contains 5-10 ppm naturally occurring uranium, thorium, and radium), there is also granite in the soil, building materials such as “cinder blocks” (made from the previously mentioned coal fly ash and its 8-20 ppm uranium), naturally occurring radium found in drinking water in areas using deep wells[8], the natural radon gas emitted from rock, and even emissions from our color TV sets.

So, if you truly believe that any exposure to radiation is dangerous, I am certainly not going to argue with you. But if you believe this, what you need to do is clear:
· immediately give up rock climbing and mountaineering (proximity to natural radioactive materials in the rock),
·  forget about that Denali or Himalaya expedition (higher altitude = higher exposure to cosmic radiations),
·   forget about those granite counter tops in the kitchen,
·  get out of the mountains immediately,
· move to sea level at the equator - but don’t fly there (an airplane flight will increase your exposure to extraterrestrial radiation sources),
·   live in a grass shack,
·  get rid of all your polypropylene and fleece clothing (the natural static electricity attracts radon),
·         and: do not watch a color TV.

Some of us, however, are probably not ready to do all of this.

With all the Natural Radiation Sources, why is Uranium mining - now becoming an Issue?
There is increased uranium mining throughout the world because in addition to the 440 operating nuclear power plants, there are additional nuclear power plants being constructed in China, Finland, France, the Middle East, and now in the US. Our electricity in Colorado comes from Xcel Energy – which owns 3 nuclear power plants in Minnesota. This is occurring because there is widespread recognition that if society needs the electricity, nuclear power plants are a significantly more benign way to generate that electricity than burning fossil fuels – which also emit radiations. That would seem to be a “no-brainer”. But to use the uranium, it needs to be mined and then milled to concentrate the uranium.

The natural occurring uranium in the earth in many locations built up in geological concentrations that are higher than average in the earth’s crust. Some of those locations of natural geologic concentration just happen to be in: Colorado, Wyoming, Utah, and New Mexico. The background radiation doses in these areas, not surprisingly, is already higher than average. The natural concentrations of radioactive elements in drinking water from deep water wells in these areas would also be, higher than average, before there was any mining. The key environmental safety issue in uranium mining is whether: activities associated with mining result in dramatically increased transport of uranium (and its associated radiation exposure of the public) to levels which are above and beyond natural exposure levels - and that would not have occurred had the uranium simply been left buried in the ground.

Isolating radioactive materials deep in the ground is recognized as a good way to shield people on the surface from excess radiation hazards. Uranium mining in the 1950’s and 1960’s was not done with the current attention to environmental protection and there were major issues throughout the western states involving improper surface disposal of radioactive mine tailings piles. These mine tailings brought materials to the surface that had higher than background level radiation sources. The tailings were disposed of the same way the mining industry had historically disposed of all other mine and mill tailings from mines that we see around Colorado: they were just piled up on the surface not too far from where they were taken out of the ground, or milled. Our old abandoned gold and silver mines and mills are a good example of this.

To address these types of mining concerns, the Environmental Protection Agency (EPA) set standards in the 1970’s on doses which future mine operators must control their operations in order to be able to operate. The EPA standards do not require “Zero-radiation-doses”, not because the EPA likes the mining companies – but as noted earlier: Mother Nature did not present us with a Zero radiation dose environment to begin with. It is these standards that any proposed uranium mining activity in Colorado would be regulated against. The State of Colorado’s Division of Reclamation, Mining, and Safety indicates that as of 2009, there are ~1,700 active mines of all types in our state, including: 35 uranium mines which hold permits, and 28 uranium prospecting permits. To obtain a permit requires demonstration that appropriate state and federal guidelines are complied with - and the posting of a surety bond. The purpose of the surety bond is to assure the availability of funds to clean up a site should the mining operation go bankrupt. The state of Colorado currently holds over $400 Million in such bonds and sureties for mines within Colorado to assure mine operators meet their obligations to reclaim their sites when mining activities are ended.

What has become a recent development is the concept of “in-situ leach mining” of uranium which does not necessitate large surface mines and dealing with accumulated mine debris materials on the surface – which was clearly an issue with many of the older uranium mines throughout the west. About 20% of all world uranium mining is now done in this manner. The process works by injecting a solution containing a combination of sodium bicarbonate and lots of dissolved oxygen into wells drilled on the periphery of a known uranium deposit and taking suction from a well drilled in the center. The combination increases the ability to dissolve and leach portions of the underground uranium allowing it to flow towards the well taking suction from the deposit. The process has been evaluated by the Nuclear Regulatory Commission (NRC) and Environmental Protection Agency (EPA) and found to be acceptably safe under appropriate geology and hydrology conditions.  This means that the doses to the public would not be dramatically increased above what we are already exposed to here in Colorado.

My Personal Take on all of this?
Professional societies such as the International Council on Radiological Protection (ICRP) have established dose limit guidelines for protecting the public health and safety that are used throughout the world. These guidelines are incorporated in regulations used by health and safety regulators such as EPA, and the Colorado Division of Reclamation, Mining and Safety. If private companies desire to mine uranium they will need to comply with these guidelines. If people living in a county near a proposed uranium mine object to the activity, they should at least be honest and admit it is more due to their own desires to control “their personal environment”. What I object to is the false alarmist statements that any additional radiation doses are a health concern and by eliminating uranium mining it would reduce public exposure and thus public risk. It won’t. Amid the already very large natural background radiation present in Colorado, it will only shift the very small radiation doses from uranium mining to the very small radioactive doses from coal burning and coal ash disposal. I’m just not convinced burning that much more coal is such a good idea.

Author Profile:
John Bickel is a 1972 graduate of the University of Vermont and received an MS in Physics in 1974, an MS and subsequently PhD in Nuclear Engineering from Rensselaer Polytechnic Institute in 1980. He has 36 years of professional experience working in nuclear power plants in the US, Europe and Asia. He has been a consultant to the US State Department, the Lithuanian and Czech Nuclear Regulatory Authorities, the Korean Peninsula Energy Development Organization (KEDO), and the International Atomic Energy Agency (IAEA) in Vienna. He has been a member of the Colorado Mountain Club since moving to Evergreen Colorado in 2000, and served as Co-Director of the Ski Mountaineering School and Director of the Avalanche Safety Schools. He was elected to the Denver Group Council in 2004 and served as Chairman of the 4,500 member Denver Group in 2007-2008.

[1] There are large pumped storage hydroelectric facilities in both the French and Austrian Alps. Any Club members who have ski toured in the Alps have likely seen either the Lac de Dix in Switzerland or the Gross Glockner hydroelectric projects in Austria.
[2] A US utility tried to build a major pumped storage facility at Storm King Mountain outside of New York City more than 40 years ago but was stopped by an Environmental Group Called “Scenic Hudson”.
[3] Denmark has an installed wind generating capacity of approximately 6,000 separate wind turbines in the North Sea which generate over 2000 Megawatts or about 15% of their electrical grid requirements.
[4] “Radioactive Elements in Coal and Fly Ash”, USGS Fact Sheet 163-97.
[5]This is one of the reasons the radioactive emissions from a coal fired power plants typically exceed those of a nuclear power plant which retain the radioactive materials in the fuel. Currently, coal ash is gathered and used for making cinder blocks which can be found in virtually any residential or commercial construction effort in the US – along with its naturally occurring uranium and thorium.
[6]As one the unusual outcomes of this rise in uranium prices, it is approaching economic viability for actual recovery of uranium out of the ash generated from coal fired power plants. This has recently been demonstrated on a laboratory scale in China.
[7] K. Z. Morgan and J.E. Turner, “Principles of Radiation Protection”, Copyright 1967 John Wiley & Sons.
[8] It is worth noting that there are many areas in Illinois, Wisconsin, and the Carolinas where there is no mining yet unacceptably high radium concentrations in drinking water supplies. As an example: the radium content in Lockport, Illinois is 500 times that found in Lake Michigan water.

Tuesday, June 21, 2011

Why I Became a Nuclear Engineer

I didn't get into the nuclear engineering field by direct choice. I started out thinking maybe I would go into medicine when I first entered college. But then I realized I was really more interested in mathematics, chemistry, and physics. So: I became a Mathematics Major / Physics Minor. 

John Bickel, as a serious Physics graduate student, 1973

At the end of my senior year at the University of Vermont in 1972, I went on a field trip to the Vermont Yankee plant in Vernon, Vermont with my physics class. It was not yet operating and this was way before all the security fences and guards with automatic weapons all over the place. We met in a visitors center with an engineer from the plant who explained how the plant worked and took us on a tour. One thing impressed me at the time was the recognition just how much energy could be released from one single nuclear fission reaction. From physical chemistry courses I knew that oxidation of hydrocarbon based fuels could yield somewhere between 2-8eV (electron volts) of energy depending on the reaction. Fissioning one single uranium nucleus, on the other hand, could yield ~200million eV. That staggering difference in energy yields stuck with me more than the piping and valves I saw inside the plant.

Yes, I got one of those simulated fuel pellets at Vermont Yankee

I finished a Master of Science Degree in Physics in 1974-- but quickly realized there was very little work in physics available. It was after the first Oil Embargo of 1973, the US economy was in shambles, and gasoline for my Fiat Spider sports car had risen from 34 cents/gallon to $1.25/gallon. It was at this point I decided to transfer over to a Nuclear Engineering program where I could possibly use some of the physics I'd learned. I talked to faculty at MIT and later RPI -- and found there were good research fellowships available at RPI almost for the taking. Living costs in Boston vs. Troy, New York cemented my decision to study at RPI. So my wife and I loaded up a U-Haul van and we were off to Troy NY.

Graduate school at RPI was pretty intensive academically - even though I had a leg up on the Mechanical Engineer types. I cruised through nuclear physics and neutron physics - but reactor engineering and fluid flow was all new. I especially recall the critical reactor lab where I did my first reactor start-ups. I remember the radiation instrumentation laboratory where we learned how to calibrate various types of gamma and neutron detectors. We had to build counting circuits and discriminator circuits - real practical skills. I also remember the homework. My wife recalls I would come home and work until 1-2AM almost every weeknight. I had learned as an undergraduate that the best way to prep for an exam was to take the text book and work out every problem in the back of each chapter -- an in particular any problem not assigned by a professor as a regular homework problem. (It usually turned out these were good candidates for exam questions.)

As my Masters Degree project was coming to an end, I started looking for employment. After job interviews with Knolls Atomic Power Lab (KAPL), General Electric, and Combustion Engineering (CE) - I decided the job offer at Combustion Engineering looked like the most interesting opportunity. I started work in September 1975 in Windsor, Connecticut. It was an incredible era for new nuclear engineering graduates - possibly equivalent to being an aerospace engineer after President Kennedy challenged NASA to go to the moon. I felt I was part of a young generation that was going to work to reduce America's dependence on imported foreign oil. CE already had operating reactors in Michigan (Palisades), Nebraska (Ft. Calhoun), and Maine (Maine Yankee) - and a dozen orders for new reactors in Arkansas, California, Florida, Texas, North Carolina, Louisiana, Arizona, and Washington.

My first assignment was in the Instrumentation and Controls Engineering department. On my first day my new boss took me aside and told me I had to learn about the dynamics of the CE pressurized water reactor. He piled up a number of training manuals that I had to read and understand before I could really do any useful work. So for weeks I read manuals, the CE System 80 Standard Safety Analysis Report, and computer code manuals. I then learned how to use a system simulation code called CESEC to figure out timing requirements for generating reactor trip signals. Within a year, as a 25 year old, I was helping design reactor trip systems by doing calculations on timing of events and confirming functional requirements. Later I became involved with the design analysis of the Reactor Power Cutback System, the Digital Core Protection Calculator System, and the Control Element Assembly Calculator System. I found out that CE would pay for me to continue my graduate education even to the point of getting a PhD -- so I put through the paperwork, and one thing lead to another.

Many years later (2006) I was a contractor to USNRC doing an audit at the Palo Verde Nuclear Generating Station and I saw the operators console for the Reactor Power Cutback System in the control room and started staring at it. A young reactor operator came up to me and inquired what I was looking at so intently. I told him I was looking at the RPC operators console. He asked me if I knew about "what it was - and how it worked?" So I told him: "Yep. I designed it back in 1978."

John Bickel (right), Consultant to Swedish Nuclear Power Inspectorate
at an OECD meeting in Paris