從1954年開始，澳州就已經開始進行鈾礦開採，目前有四個鈾礦礦場（Olympic Dam, Ranger, Beverly, Honeymoon）正在進行開採，另外還有許多地點正在申請開採許可執照。澳洲蘊藏的礦產資源之豐富是世界聞名，其中鈾礦就佔世界鈾礦總量的31％。光是2012年，澳洲就生產了8244噸的氧化鈾，也就是所謂的黃色蛋糕（yellow cake）。僅次於哈薩克和加拿大，澳洲作為目前世界上排名第三的鈾礦生產國，他們出口大量的鈾礦，但國內並不使用核能發電，相對地，澳洲的能源非常依賴使用煤炭、天然氣和石油。
以下為整理出來的訪談內容，附上中英文對照：
問：暮德教授能簡單跟我們介紹一下鈾礦開採的過程嗎？鈾礦開採要經過哪些程序？
答：首先，他們從礦場把礦石挖出來，接著把礦石碾碎成小砂石，再送到礦場附近的工廠進行的化學處理，經過浸出和淘選之後，就變成了可以出口販賣的濃縮鈾氧化物，也就是所謂的黃色蛋糕。為了讓黃色蛋糕成為核電廠能夠使用的鈾燃料棒，氧化鈾必須要再經過濃縮（enrichment）。澳洲並沒有鈾濃縮廠。因此，澳洲的黃色蛋糕都會出口到像美國這樣的國家進行濃縮處理。
問： 從影片 《能源救星（Climate of Hope）》 ，我們知道鈾礦開採需要大量的淡水，並且會產生大量的輻射污染廢棄物。那目前澳洲採礦場的廢棄物和污染管控做的如何？
答：這要看是哪個場，每個採礦場的條件都不一樣，但一般來說，目前的礦場回復和清理是不夠完善的。我們通常認為，一個合理的礦場回復，應該至少要讓當地的自然系統在5年或10年後能夠獨立正常運作。然而，我們從Google地圖的衛星空照圖就可以看到在澳洲的採礦場都非常糟糕，很明顯的沒有做好礦場回復措施。
澳洲政府對於採礦業的管理和限制非常少，有時政府規定採礦公司必須把露天開採所造成的坑洞填補起來，結果他們就直接用低放射性的廢物（按：這裡指的是採礦所剩下來的低輻射尾礦）投入坑洞裡面（澳洲的Ranger礦場），甚至完全不處理，只把低輻射尾礦覆蓋住，就拍拍屁股走人。那些只有稍微覆蓋的尾礦非常有可能會污染周圍地區，像是雨水會把尾礦中蘊含的低輻射物質沖刷出來，進一步污染周邊地區的土壤和水，而這些低輻射的灰塵，可能會被風吹到周邊地區。
開採鈾礦的過程中，水污染問題特別嚴重。鈾礦開採時，會使用清水來進行一般的清洗，進行浸出淘選時循環使用的清水是污染最嚴重的水，很多時候這些工業用的循環水並沒有妥善處理，在採完礦之後就直接留在礦場。
問：那些現場在進行鈾礦開採的工人，他們的工作條件如何？
答：工人都有發給防護衣和口罩，然而即使有防護衣讓工人抵擋α和β輻射，但仍無法抵禦γ射線。此外，工人並不清楚吸入放射性塵埃可能造成的健康風險，想要防止工人吸入放射性粉塵是非常困難的。目前我們無法得知鈾礦開採對這些工人的影響如何，因為根本沒有建立任何調查追蹤系統，無從得知10年、20年之後這些工人過的如何，礦業公司也懶得做任何研究，因為他們很認真的相信鈾礦開採是安全的。
問：我聽說有研究顯示，因為鈾礦的密度和純度下降，未來鈾礦開採的能源強度會逐漸增加，（按：即鈾礦開採必須投入更多資源和能源）而且鈾礦的存量可能不夠提供目前的核電廠長期使用，這是真的嗎？
答：這是一個問題，但不是個大問題。我們現在有一大堆的鈾礦，而且也一直在發現新的鈾礦礦場。目前可用的八氧化三鈾（U3O8）濃度是0.01％〜20％之間，從礦場開採出來的八氧化三鈾的濃度大概介於0.1％〜0.5％之間，仍然在可用範圍之內。現在全世界預計有總量約1000萬噸的八氧化三鈾，我們目前只用了7萬5千噸的八氧化三鈾，也就是我們目前只用了0.75％的總存量。
從鈾礦開採的角度來看，鈾礦的濃度並不是唯一值得擔心的事情。鈾礦開採並不像理論上那樣簡單，礦場的地理條件會造成很大的影響，開採的難易度跟採礦範圍多大、開採地質如何、是否容易開採、是否容易加工處理有關。鈾礦開採的能源強度與這些地理條件有關，有些採礦場的礦石很難加工處理，有些則很容易，像在俄羅斯，就有個50年前就發現且世界聞名的鈾礦礦場，但沒有人進行開採，它從未被開發，因為就算開採出來也太難加工處理了，不符合成本。
但即使這個俄羅斯的採礦場真的開採並且進行加工處理，這些開採出來的鈾礦濃度仍然是在合理的範圍之內。
舉個例子，納米比亞的Rossing礦場開採出來的鈾礦濃度為0.04％，澳洲的Ranger礦場是0.3％，加拿大的McArthur礦場是20％。然而，加拿大McArther礦場可能不比澳洲Ranger礦場來的有效率，因為McArthur礦場的放射值太高，沒辦法靠人工進行採礦，他們必須使用機器遠程控制開採。不同的礦場有不同的條件和狀況，有時很難加工處理可能是問題，可能會讓Ranger礦場比McArthur礦場更有效率。有些鈾礦很淺，非常容易開挖，但很難進行化學加工處理，有些鈾礦藏在很深層的地方，不管怎麼樣都很難處理。各個礦場的條件都各不相同，所以這要看你看的是哪個礦場。但真正的問題都不在這裡，而是在鈾礦的使用。
問：總是有人說，如果我們不選擇核電，我們就只能選煤炭和天然氣來發電，我們真的只能在核電和火力發電兩者之間做選擇嗎？
答：如果我是你，我不會拿這兩個來比。一個1GW（100萬千瓦）的核能反應爐，一年會用掉大約250噸的鈾礦，這些鈾礦開採過程產生平均30噸的二氧化碳排放量，這還只是鈾礦開採階段而已。每一噸的鈾礦就會排出30噸的二氧化碳。所以，我們把30乘以250，也就是一年光鈾礦開採就會排出7500噸的二氧化碳。這不包括鈾濃縮處理、運輸和其他部分的排放。
但相較之下，火力發電大概則是一年300萬噸的碳排放量。所以，即使鈾礦開採因為鈾濃度下降變得必須投入更多能源（造成更多的碳排放）才能進行開採，再怎麼樣，比起煤炭發電核能發電的二氧化碳排放量總量仍然是非常低的。但我並不會擔心這個問題。沒錯阿，我們知道未來鈾礦開採的能源強度會增加，鈾礦濃度變低等等。但我們有一大堆的鈾礦，這種現象會發生，但也是非常緩慢地發生。相較於煤炭發電，目前的鈾礦存量非常足夠，而且能夠維持在低碳排的狀態。
沒錯，我們知道未來要花更多的能源去開採鈾礦，但就像我前面所說的，這取決於你看的是哪個採礦場。鈾礦真正的問題在於安全性，在於廢棄物處理，在於核武。從過去到現在的70年一直都沒有改變。
問：在您看來，我們如何能夠解決能源問題，同時又能夠面對氣候變遷問題？
答：我們必須要廢除煤炭和天然氣的使用，這是肯定的。然後，我們再來要比較的是再生能源與核能發電。
我們必須回顧我們的能源使用效率，重新定義我們的基載電力，混合使用各種綠色能源，就能夠解決這個問題。
在澳洲我們有很多選項，我認為台灣也可以採用其中一些，像是風力、潮汐發電、太陽能等等，還有很多是還沒開發出來的。涉及到再生能源的時候，台灣、印度、芬蘭會有非常不同的配置方式。從我目前的研究以及我同事的研究報告中，我知道再生能源是可能的，已經有人做過一些評估，知道要如何重新設計世界的電力系統和輸油系統。我們知道該怎麼做，這不是技術問題，很多時候是經濟和政治的問題，台灣的解決方案可能和澳洲的大不相同，但它是有可能的。
這可能意味著未來澳洲可能成為能源生產國，甚至出口能源賣到印尼或台灣或其他地方。這沒什麼問題。像是在北非，他們在港口蓋了大量的太陽能發電站，把所有電力都出口到歐洲。
我們是可以有其他選擇的。風力發電機並不會馬上開、馬上關，它會開一陣子，然後慢慢停下來。在這之間就創造了時間，這個時間就是讓我們開啟備用發電機或其他發電的機制。海上風力發電也是這樣，岸上的風速會有快有慢。但在海面上，風力一般來說比較穩定，這樣就不會有太多的上下差，可以產生更多穩定的電力。而且設置在海上的話不會有社區和其他的顧慮，可以建立更大規模的發電設施，我記得好像已經有人在歐洲的哪裡蓋了一些5MW的發電機。
有人在蓋海上發電設施的時候一起把小渦輪放上去，這樣就可以從同一支發電機同時獲得風能和潮汐能。還有很多有創意的想法可以去做，就像我說的，這並不是技術問題，我們都知道目前的技術是可以重新形塑世界的用電體系，但是這些要靠政治和經濟來實現。
每個地方的解決方案可能會有所不同，它意味的是，不能只用過去基載電力的概念來看，而要用新的角度來看事情。台灣的基載電力跟澳洲的可能不一樣，然而，澳洲的基載電力是假的，火力發電廠不可能馬上打開或馬上關掉，它要花一天的時間讓熱度達到高峰，再花一天的時間冷卻回到低點。凌晨3點或5點的時候，大家都在睡覺，這些電力沒什麼人在用，雖然有一些工廠在使用但不多，我們產出的電力其實遠比我們需要的多。有些作法像水力發電系統，他們會利用多餘的電力把水抽到高處，這樣之後就可以再利用水力發電。
我們一開始就不需要這麼多電，也就是說，我們其實並沒有像我們想像中的那樣，需要這麼多的基載電力。這有點像個迷思，人們會說提供基載電力就是我們需要核電廠、火力發電的原因，但並不是這樣的。如果我們重新檢視真正合理的能源需求，包括個人需求、產業需求以及其他的部份，會發現其實我們並不需要這麼「大規模」的基載電力。需求其實是有上下波動的，而這樣的特性跟再生能源也相同。
檢查使用效率一直都是一個重新評估能源供應的好方法。最好的是，一開始就不需要使用能源，現在開始節能，長久下來會減少很多能源的浪費，從系統的角度來看，我們知道投資在改善能源使用效率上不但便宜得多、具有經濟效益、減少財政支出，而且是對環境友善的，且讓我們可以逐步轉向使用再生能源。很多人試圖營造出一個氛圍，好像「我們做不到這件事」，但事實並不是如此，我們做的到，這不是技術問題。
如果放大到地球的宏觀角度來看，我們不可能不惜任何代價地一直增加能源供應。隨著人口越來越多，我們勢必要減少能源消耗，特別是氣候變遷等問題越來越嚴重。
這才是主要的戰場。
---以下為英文原文訪問稿---
Gavin Mudd is a senior lecturer in Environmental Engineering of Civil Engineering Department in Monash University, specialize in sustainable development of groundwater, sustainable mining, environmental impact, management and rehabilitation of mine wastes, groundwater resources and management. On June 9th we had a short interview regarding his point of view toward the uranium mining in Australia and a general view of the current energy system development in the world.
Australia's uranium mining has been established since 1954, and four mines (Olympic Dam, Ranger, Beverly, Honeymoon) are currently operating. More sites are proposed to development. Australia's known uranium resources are the world's largest - 31% of the world total. In 2012, Australia produced 8244 tonnes of uranium oxide concentrate (the so-called yellow cake). Australia is the world's third-ranking producer, behind Kazakhstan and Canada.
Australia exports uranium mine but uses no nuclear power. Instead, Australian energy relies heavily on coal, gas and petrol.
Q: Can you generally tell us how uranium mining works? What is the process of uranium mining?
A: First of all, they will dig out ore from sites. The ore will be crushed and grind into pebbles, and then send to the chemical process factory on the site. After the leaching and stripping process, the exportable product is uranium oxide concentrate, the so-called yellow cake. To make the uranium oxide concentrate usable in nuclear power plants, the yellow cake need to go through enrichment process. However, Australia have no enrichment factory. Therefore Australian mining sites export the yellow cake to countries like the United States.
Q: From the film Climate of Hope, we know that uranium mining requires a lot of fresh water and will generate a lot of polluted wastes. How about the current waste and pollution control in Australia mining site?
A: It depends. Each mining site varies. However, general speaking, the current recover and clean up of mining sites are unreasonable. We will say a reasonable care should at least let the local nature system function normally after 5 or 10 years. Even from the satellite view from google map, we can see the mining site in Australia are treated very poorly, and obviously the rehabilitation doesn’t work out well.
The Australian government has very limited regulation on mining. Sometimes company are required to refill the open cut (Ranger) with low-radioactive waste, some simply cover the tailing and then leave it there for decades.This can pollute the surrounding area because rain can wash the pollution down to soil and further pollute the water and soil of the surrounding area, or the contaminated dust can be blown to surrounding area.
The water pollution is especially an issue. When doing the uranium mining, the water are used for generally washing and cycle water for processing wash. The latter one is the most polluted but a lot of times it will be left on the mining site, untreated.
Q: What about the workers’ working condition on site?
A: The workers are giving clothes and masks. However, even workers are in clothes that they can resist alpha and beta radiation, but still cannot resist gamma radiation. In addition, workers are not informed about the possible health risk of inhaling radioactive dusts. And it is very hard to prevent workers inhale radioactive dusts in. Also, we have no idea how these uranium mining workers are being influenced because there is no tracking system to see what happen to them after 10 years, 20 years and so on. Mining companies don’t bother to do the research, they genuine believe uranium mining is safe.
Q: I’ve heard there are researches show that the energy intensity of uranium mining will increase in the future because of the uranium density is dropping. Also the stock of uranium is not going to be enough to support nuclear power plant for long. Is that true?
A: Its an issue. but not the big issue. There are heaps of uranium and people are still finding more. The usable U3O8 density for mining is between 0.01%~20%. The current density of U3O8 from most of the mine is 0.1%~0.5%, still within the range. And right now in the world we have in total about 10 million tonnes of U3O8 and we’ve been using only 75,000 tonnes of U3O8. Thats only 0.75% of the total stock.
When you look at the mining stage, the grade of uranium ore is not the only thing you need to worry about. Uranium mining is not as theoretically as it should be. Geographical elements can influence a lot. Its about how big the deposit is, the nature of the deposit, is it difficult to deposit, is it easy to process. The energy intensity of uranium mining varies. Some project are extremely hard to do that, others are rather easy. Some are really hard like in Russia there’s a site known for 50 years in the world, but no one deposit. Never being developed because its too difficult to process.
Even the one in Russia got processed, they are still within reasonable grade.
For example the grade of uranium in Rossing (Namibia) is 0.04%, in Ranger (Australia) is 0.3%, in McArthur River (Canada) is 20%. However, the deposit in McArthur might not be as easy as in Ranger. Since it is too radioactive in McArthur, the deposit cannot be done manually, they have to use machine to remotely control the deposit. Therefore different sites have various situation. Sometimes hard to process can be a problem, might makes Ranger more efficient than McArthur River. Some uranium ore are really close to the surface, extremely easy to dig up but hard to chemical process. Other are deeper and very hard to process anyway. The condition varies, depends on which site you’re looking at. The real question is the use of the product.
Q: There is always a debate saying if people don’t choose nuclear power then we can only use coal and gas as our electricity source. Is it really that we can only choose between the two?
A: If I were you I won’t compare the two like this. If you look at a 1 giga watt nuclear reactor, it needs a 250 tons of uranium mine a year, roughly, which will generate average of 30 tons CO2 emission just at mining stage along. 30 for every ton of uranium mine. So if you times 250 with 30, that’s 7500 ton a year, just from uranium mining. That hasn’t include enrichment, transporting and else.
However, compare to coal fire power station, you’re probably looking at 3 million ton for one coal fire reactor per year. So even if uranium mining does go carbon intensive, the uranium intensity goes down, the total amount of CO2 emission of nuclear power is still very low. I don’t worry about that argument. Yes, we know there is going to be a growing energy intensity as the uranium goes lower grade and so on. But there’s heaps of them. Its going to be very slow. There are enough amount of uranium to produce and still maintain in low carbon intensity, compare to coal. Yes we know there is going to be higher power intensity, but it really depends on how you deposit as I said.
The real big issue is safety, is waste, is weapon. That hasn’t change in the past 70 years.
Q: In your opinion, how can we solve the energy problem and deal with climate change at the same time?
A: We will definitely need to get rid of coal and gas. That’s for sure. Then it will become nuclear energy versus sustainable energy.
We have to look at our energy efficiency and re-define the base load of the electricity. The combination use of various green energy can solve the problem.
In Australia, we have plenty option, and I think Taiwan can adopt some of them like wind, tidal, solar panel and so on. There’s a lot can be done.Taiwan, India, and Finland will have very different configuration when it comes to renewable energy. But from all the work I know, I read from my colleague and I know that renewable energy system can be done. People have done some assessment, you know how to re-engineer the worlds electricity system and oil transfer system. We know how to do all lot of that. It’s not a technological problem, a lot of them is economic and political problem. The solution in Taiwan might be very different from the one in Australia. But its possible.
It may mean Australia will become energy producer and then export to Indonesia or Taiwan, or whatever. That’s fine. Like in North Africa, where they build a massive thermo solar power station right across its harbor. And export all its electricity to Europe.
There’s option. Wind turbine doesn’t just suddenly turn on and off. It start to go on for a while and then goes down. You’ve got time. That’s the time you need to turn on backup generators or you got other things online and so on. Offshore wind as well. Generally wind speed can be vary. But offshore out in the sea, the wind is generally more constant. So you don’t get as much up and down, and can generate a lot more constant. Also you don’t have community and other things, so you can build the biggest scale offshore. I think some people have built some 5 mega watts each in Europe.
But also, when you’re putting foundation into the sea, put little turbine in. So then you can have both wind and tidal power from the same foundation, the same structure. There are a lot of creative ideas. Like I said, its not a technology problem. We know that the current technology is enough to re-power the world system. Its politic and economy to make it happen.
Solution for places might be different. But it means you don’t just use the concept of base load. We have to think differently. The base load we have in Taiwan might be different from Australia. However, a lot of times the base load with have in Australia is artificial. You can’t turn the coal power station on and off very quickly. It takes you a day to make it up to the peak and a day back to low point. So when they operate it at 3 am or 5 am, when everyone’s asleep, it’s not doing much, although there are some industry using. We are generating more power than we need. So what they do, for example hydro system, they use the excess power to pump the water up. So that way the water will coming down again.
We don’t need that much electricity in the first place. That means we don’t need as much base load as we think we do. Its sort of a myth that we need base load that’s why we need nuclear we need coals. No. If we actually look at our reasonable energy demand, by personally, for industry, and things like that, we don’t need this massive base load. They actually goes fluctuate, which fits renewables.
Energy efficiency is always one of the best way to look at energy supply. The best energy you have is the one you don’t need at the first place. You know you can start to achieve the biggest saving in the long run. From the system point of view, we know we invest energy efficiency is much cheaper, economically, financially, as well as environmentally, and gradually switch to renewables. Plenty of people have developed the scenario that we are unable to do that. No. It can be done. Not a technological problem.
If you zoom back to a hole planet point of view, you cant just keep increasing our energy supply at any cost. As population goes up, we have to reduce our energy consumption anyway. Especially with issues like climate change and things like that.
This is the primary game.
A: We will definitely need to get rid of coal and gas. That’s for sure. Then it will become nuclear energy versus sustainable energy.
We have to look at our energy efficiency and re-define the base load of the electricity. The combination use of various green energy can solve the problem.
In Australia, we have plenty option, and I think Taiwan can adopt some of them like wind, tidal, solar panel and so on. There’s a lot can be done.Taiwan, India, and Finland will have very different configuration when it comes to renewable energy. But from all the work I know, I read from my colleague and I know that renewable energy system can be done. People have done some assessment, you know how to re-engineer the worlds electricity system and oil transfer system. We know how to do all lot of that. It’s not a technological problem, a lot of them is economic and political problem. The solution in Taiwan might be very different from the one in Australia. But its possible.
It may mean Australia will become energy producer and then export to Indonesia or Taiwan, or whatever. That’s fine. Like in North Africa, where they build a massive thermo solar power station right across its harbor. And export all its electricity to Europe.
There’s option. Wind turbine doesn’t just suddenly turn on and off. It start to go on for a while and then goes down. You’ve got time. That’s the time you need to turn on backup generators or you got other things online and so on. Offshore wind as well. Generally wind speed can be vary. But offshore out in the sea, the wind is generally more constant. So you don’t get as much up and down, and can generate a lot more constant. Also you don’t have community and other things, so you can build the biggest scale offshore. I think some people have built some 5 mega watts each in Europe.
But also, when you’re putting foundation into the sea, put little turbine in. So then you can have both wind and tidal power from the same foundation, the same structure. There are a lot of creative ideas. Like I said, its not a technology problem. We know that the current technology is enough to re-power the world system. Its politic and economy to make it happen.
Solution for places might be different. But it means you don’t just use the concept of base load. We have to think differently. The base load we have in Taiwan might be different from Australia. However, a lot of times the base load with have in Australia is artificial. You can’t turn the coal power station on and off very quickly. It takes you a day to make it up to the peak and a day back to low point. So when they operate it at 3 am or 5 am, when everyone’s asleep, it’s not doing much, although there are some industry using. We are generating more power than we need. So what they do, for example hydro system, they use the excess power to pump the water up. So that way the water will coming down again.
We don’t need that much electricity in the first place. That means we don’t need as much base load as we think we do. Its sort of a myth that we need base load that’s why we need nuclear we need coals. No. If we actually look at our reasonable energy demand, by personally, for industry, and things like that, we don’t need this massive base load. They actually goes fluctuate, which fits renewables.
Energy efficiency is always one of the best way to look at energy supply. The best energy you have is the one you don’t need at the first place. You know you can start to achieve the biggest saving in the long run. From the system point of view, we know we invest energy efficiency is much cheaper, economically, financially, as well as environmentally, and gradually switch to renewables. Plenty of people have developed the scenario that we are unable to do that. No. It can be done. Not a technological problem.
If you zoom back to a hole planet point of view, you cant just keep increasing our energy supply at any cost. As population goes up, we have to reduce our energy consumption anyway. Especially with issues like climate change and things like that.
This is the primary game.
