ISR Uranium Mining - A New Method Explained

ISR uranium mining is responsible for nearly all U.S.areas of Wyoming where we would be mining,
uranium mining (except for recovery throughalkaline is a far more suitable means of in situ mining.
phosphates). More than 20 percent of global uraniumBy using alkaline it is a lot easier to clean up and to
mining now comes from the in situ recovery method,restore the aquifer afterwards. Acids can react on
predominantly through In Situ Leach (ISL) mining inmany things besides uranium. They can dissolve
Kazakhstan and in Australia.pyrite, sulphides and other minerals in the sandstone.
Because of the large number of ISR uranium projectsAcid can release a lot more undesirable things into
on the horizon within the next ten years, both in thethe formation that can make it more difficult, in some
United States, Kazakhstan and Australia, the in situcases, to recover the uranium, and make it more
(ISR) uranium mining method will provide U.S anddifficult to do a proper restoration job. The alkaline
global utilities with tens of millions of pounds of newlyprocess is a lot cleaner process, and it's a lot easier
mined uranium by 2020.to restore the aquifer.
We discussed the basics of ISR uranium mining withStockInterview: Tell us about constructing an ISR
Bill Boberg, chief executive of UR-Energy, whosewell field for mining the uranium.
company plans to mine Wyoming's Lost Creek andBill Boberg: The wells are installed similar to most
Lost Soldier uranium deposits using the in situcommon water wells - with PVC piping. PVC casing
recovery uranium mining method in 2008. Wewould be cemented in place, and then piping similar to
discussed many of the environmental type questionsthat used for irrigation would be used to transport
our readers wanted more information about.the water to the injection wells. Similar piping would
StockInterview: How did the uranium actually get intotake the same water, coming out the production
the sandstones and become a roll front deposit?well, when moving it to the ion exchange column.
Bill Boberg: Natural processes caused the uraniumWhen you come right down to it, this is basically a
deposit to be in the aquifer in the first place. Thewater plant. You are dealing with piping and water
uranium was deposited by the naturally flowingand oxygen and bicarbonate of soda. There's not
ground water when the natural oxygen in the groundmuch of anything that is going to cause anybody a
water was exhausted due to natural chemicalproblem.
reactions with minerals and organic material containedStockInterview: There have been concerns about
in the sands of the aquifer itself. Uranium is still beingwater use in certain parts of the United States. Will
carried by ground water flowing to the deposits. Theyour company be consuming large amounts of water
flowing ground water is also naturally leaching partswhen mining at Lost Creek or Lost Soldier?
of the deposit and re-depositing it a short distanceBill Boberg: Consumption will be really low because in
away. This is really a very common natural processsitu mining is basically a closed process. We use the
that's happening in many aquifers.ground water that is in the uranium deposit itself. We
StockInterview: When you mine using the ISRpump it out. We bring it to the surface. We charge it
method, do you destroy or contaminate an aquiferwith the oxygen and bicarbonate of soda. Then we
where you are mining?recirculate it back through the formation. Ninety-nine
Bill Boberg: There are probably thousands of uraniumpercent or more of the water stays in the formation.
deposits throughout the world of varying quality inWe only have to take out and dispose of one-half to
sandstones, which are also aquifers. Only a fewone percent of the water that we are producing.
hundred of these will contain sufficient uranium toStockInterview: While ISR mining how does your
eventually be mined. It's there, and if it is mined,company ensure that radiation does not escape
most of the uranium that was in the aquifer willbeyond the aquifer and contaminate the ground
actually be removed from the aquifer instead ofwater people or livestock drink?
staying there. The in situ (ISR) mining process simplyBill Boberg: The key is a very extensive monitoring
reverses the natural process that placed the uraniumprogram through a system of monitoring wells. These
there in the first place. It's really a pretty simplesurround the well fields. Shallow monitor wells watch
process. The restoration process, after the mining isover any overlying drinking water aquifers. The
completed, actually returns the aquifer back to itsmonitor wells are very close to the well field. The
pre-mining conditions. There is no way the aquifer ismining process is done by pumping at such a rate so
contaminated or destroyed (by ISR mining).it brings the flow toward the production wells
StockInterview: Many environmentalists claim that bythemselves. This assures the ground water flow is
removing the uranium, you are changing the aquifer.not moving the mining solution away from the
Is the aquifer much different than before mining tookproduction wells. From a mining company's viewpoint,
place?it would be a huge waste if we could not control the
Bill Boberg: It's probably not a lot different. Thefluids. We would have a huge expense in not being
formation of uranium deposits in the sandstones is aable to have the fluids go where we want them to.
result of oxygenated ground waters that came fromAs a result, we carefully set up the process to make
the surface, carrying uranium which is depositedsure the fluids are moving the way we need them to
when the oxygen is depleted or finally exhausted.go. The monitor wells assist us in knowing that we
The deposit is in place in the sandstone. As freshhave control of the water flow. The monitor wells
oxygen is brought down to that point, it willalso assist the state government and the Nuclear
re-dissolve and move the uranium further along.Regulatory Commission in assuring that we have our
StockInterview: How do you know where in thefluid flow under control.
deposit to inject the fresh oxygen?StockInterview: What happens when the bells go off
Bill Boberg: On one side of the deposit is what we callor the alarm sounds at the monitor wells?
altered or oxidized sands. On the down dip side ofBill Boberg: If any of the wells give a suggestion of
the deposit are the reduced sands. There is nothe potential of mining solutions getting into the
oxygen in those sands. Any fluid that carries uraniumvicinity of the monitor wells, we would immediately
into the reduced sands is going to use up the oxygenstop the injection of solutions, and use 'overpumping'
and immediately deposit the uranium by naturalto draw the solutions back into the mine area.
processes. The mining process adds additional oxygenMonitor wells are there to ensure we can see what's
to the water in the deposit itself to cause thehappening in the area. They are there to enable us to
uranium to go into solution. Then, it can be pumpedensure our operations are being done properly. If a
up to the surface. The area of reduced sand that issolution does happen to get into the monitor well,
downstream from the deposit is still there. It is thethat's not really such a bad thing. It's telling us we
contact between the altered or oxidized sand andneed to make some corrections and move forward.
the reduced sand that causes the uranium to beMonitor wells help us develop better controls in the
precipitated into the sand itself. As the natural groundnatural system we are dealing with.
water flow carries the uranium into the reducedStockInterview: How do you restore the water back
sands, natural processes will cause the uranium toto it pre-mining quality?
precipitate out of the ground water, if there is someBill Boberg: The aquifer is usually restored using the
that did not get pumped to the surface andreverse osmosis process. It is a super-filtering
recovered during the mining operation.process. We can also use other techniques, like
StockInterview: How do you control the water flowreduction or bio-remediation. But, reverse osmosis is
during the ISR mining process?probably the one that would be more commonly
Bill Boberg: The fluid flow is controlled by pumping theused. More than 99 percent of the water used in the
production well at a greater rate than the injectionmining process is recirculated. It's put back in the
wells which are injecting the fluid. In other words, weaquifer after it is restored at the surface. It's just the
create a flow to the production well because it isnew volumes of newly restored water that are
being pumped at a greater rate than the fluid beingpumped back through the mined area to assure that
pumped into the surrounding injection wells. By doingit's returned to pre-mine conditions. Only the small
this, we end up with a certain amount of 'bleed.' Thevolumes of water, which are left with more
majority of the ground water is returned to theconcentration, may be either evaporated or distilled
aquifer on a regular basis. About one-half to oneto create a solid waste for disposal. Or, they would
percent of the water used in the system is actuallybe disposed of in a licensed disposal well.
'bled' out because we are pumping the productionStockInterview: Could you explain the deep disposal
wells at a greater rate - between one-half to oneprocess?
percent greater rate than what we are injecting.Bill Boberg: Deep disposal is an activity which is strictly
That's how we control the flow from the injectionlicensed and monitored by the states. It's not for just
wells into the production wells.when the mining activity is completed, but probably
StockInterview: What is the solution you'll be usingsomething to be used throughout the mining activity.
during the ISR process in Wyoming?What this amounts to is this: the waste water is
Bill Boberg: This will be an alkaline solution - basicallyinjected into a very deep rock unit. The disposal well
just the addition of carbonate and oxygen to normalis too deep and with such poor water quality that it
ground water. The carbonate could be in the form ofcould never be used for drinking water. These wells
simple bicarbonate of soda or the gaseous carbonare commonly 6,000 or more feet in depth. The
dioxide itself. The solution being used has beencontainment qualities of the deep disposal rock unit
described as not much different than Perrier®have to be able to contain the disposed water
water. The solution is not something out of the realmwithout a potential for leakage into other rock units.
of normal ground water, and would cause no oneThis is a common and well-accepted method for fluid
any problem. The combination of the carbon dioxidedisposal. It is strictly licensed and monitored. We are
or bicarbonate of soda and oxygen in the groundcurrently evaluating both our project areas, through
water is really quite a benign solution. But, it changesthe use of old oil and gas drill logs, in the area for
the chemical character sufficiently that it causes therock units which could be favorable for the installation
uranium to go into solution. It's really just reversingof deep disposal wells. As I said before, the deep
the process that caused uranium to be deposited indisposal well is for a small percentage of the whole
the first place. Uranium is precipitated in a 'reducedvolume of water that will be handled.
form.' The alkaline solution just reverses theStockInterview: How can the environmentalists be
deposit-forming process by using the water already inassured that the water will be restored to its
the deposit. Adding oxygen to it enables the uraniumpre-mining conditions?
to go into solution, and then be brought up to theBill Boberg: Wyoming and Nebraska have a similar law,
surface. There the uranium is stripped out on thewhich requires 100-percent bonding for reclamation.
polycarbonate resin in the ion exchange column.The bonds are a result of a calculation, depending on
StockInterview: But, other areas in the world, suchvarious qualities of the deposit and how the mining
as Kazakhstan, rely upon sulphuric acid in the in situwill be conducted, which determines what it would
recovery uranium mining method.cost the state to compete restoration if the
Bill Boberg: Sulphuric acid will not be used as part ofcompany went bankrupt, or was not able to do any
our in situ mining process. The sandstone deposits inmore work in restoring the mine. It is a complete
Wyoming region are very suitable for alkaline-type in100-percent bonding that is determined in advance.
situ mining. The use of acid for in situ mining isIt's probably in the range of tens of millions of dollars,
considered suitable only under certain geologicwhich would be required for the bonding.
conditions, particularly in areas of very poor waterCOPYRIGHT © 2007 by StockInterview, Inc.
quality. Where we've got good water quality in theALL RIGHTS RESERVED.