its are amenableto in-situ, or bore-hole,
mining (Shock and Conley, 1974) by
either acid or carbonateleaches.Limited
researchhas been conductedon the bacterial leachingof theseroll-front ores,but
preliminary investigations(C. Brierley,
1978b)on ore from the AnacondaCompany Jackpile-Paguatemines of New
Mexico indicate that suitable energy
sourcesare unavailablefor the bacteria,
and that the organismsloseviability when
in protractedcontactwith the ore. Present
studiesof this ore amendedwith suitable
bacterialenergysourcesareevaluatingthe
affect of hydrostatic pressure on the
bacteriaduring the leachingprocess(A.
Torma, J. Brierley,and C. Brierley,unpublisheddata). Such laboratory studies
are an attemptto sirnulatethe waterpressure exertedundergroundduring leaching. Extensivelaboratoryand field testing
is neededbeforevalid conclusionscan be
made on the use of bacteria for in-situ
leaching of western U.S. uranium reserves.
ganismswhich require temperaturesbetween30-55oC.Although theseorganisms
oxidize iron like T. ferroxidans and are
morphologicallyand physiologicallysimilar, theyrequiresmallquantitiesof simple
organic compounds.First isolated from
Icelandic, acidic thermal springs, thermophilic thiobacilli have been found to
leachtest
occur naturally in a large-scale
facility (J. Brierleyand Lockwood,1977)
and copperleachdumpsat Chino mines,
Santa Rita, New Mexico (J. Brierley,
1978),and Bingham Canyon, Utah (C.
Brierley,et al., 1979).
It is prematureto ascertainthe significanceof thermophilicbacteriain mineral
leaching.Temperatureprofiles of copper
leachdumpsshowareasin excessof 80"C
due to the exothermicoxidationof pyrite
(Beck, 1967).Such regionscould be the
site of active thermophilic bacterial
populations. However, studies to date
have neither quantitated these populations nor evaluatedtheir contribution to
metalsolubilization.
Restorationof mine sites
and wastewaters
Bacterial leaching is not confined to the
Microorganisms
are now used in the
microorganisms Z. thiooxidans and T.
restoration
mine
and mill effluents,
of
ferrooxidans. Severalother microbes affect the dissolutionof metallicsulfidesby and current researchindicatesthat some
oxidation of iron and sulfur and direct at- bacteria may play an active role in the
tack of sulfideminerals.Among the most restoration of in-situ uranium leaching
unique are the extremely thermophilic sites.
(heat-loving)and acidophilic(acid-loving)
Restorationof in-situ uranium mines
bacteria.The first of thesemicrobesto be
In-situ leaching of uranium has
characterizedwasSulfolobusacidocaldarflourished
in the uraniumregionsof south
izs (Brock, et al., 1972). Other related
Texas
and
Wyoming. The most frequent
forms have been subsequentlycharacterleaching
agents
usedin theseregionsare
ized (C. Brierley and J. Brierley, 1973;
carbonate
and
bicarbonate ions with
DeRosa,et al., 1975).These spherical
peroxide
hydrogen
as the oxidizing agent
bacteriaare about I pm in diameter,require an acid environment,and oxidize to form the highly soluble uranyl dicar(Garrelsand
reducedsulfur and iron compounds.They bonateand tricarbonateions
1965).
Christ,
obtain carbonfrom eithersimpleorganics
or carbon dioxide, and function aerobic2UO,+ 2H,O, + 4(NH.),CO,*
ally or anaerobically.Thesemicrobesare
(10)
2(NH.),UO,(CO,),+4NH.OH
unique in that they are obligatelythermophilic, requiringtemperatures
between
uo, + H,o, + 3(NH.),CO.*
45o and 80oC;somespeciesfunction at a
(ll)
(NH.).UO'(CO,),+2NH.OH
temperatureas high as 90oC.The natural
habitatsof theseorganismsare acidichot Sincethe hydroxyl formed by thesereacsprings,and although they have not been tions will attack the uranyl carbonate
specificallyidentified with any commer- complex,it is neutralizedby the addition
labora- of bicarbonate.
cial leachingoperations,extensive
tory tests confirm their capability to
enhancethe extractionof metalsfrom the
NH.HCO, + NH.OH*(NH.),CO, + H,O (12)
recalcitrant minerals chalcopyrite and
molybdenite(C. Brierley, 1977;J. Brier- Although solutions other than ammoley and C. Brierley, 1978; C. Brierley, nium carbonate and ammonium bicar1978a:'
C. Brierley,1974).
bonatecanbe used,the ammoniumcation
A few years after the discoveryof the is preferredsinceit is lessexpensiveand
extremelythermophilic,acidophilicbac- doesn't produce the swelling of clays
teria, LeRoux et al. (J9T1) reported the sometimesnoted with the sodium ion.
discovery of Thiobacillus-like microor- However.the ammoniumion doeshavea
Otherleachingmicroorganisms
August 1979
NewMexico Geology
tendencyto adsorbto baseexchangesites
associatedwith clays in the mineral formation. Ground water passingthrough
the formation tends to mobilize the ammonium ion, and there is the potential
problemof the conversionof ammonium
to nitrite and nitrate. The latter compounds have little affinity for minerals
and are freely soluble.Nitrite and nitrate
arealsohazardousto humanhealth.
Laws for the restorationof mine sites
are now being formulated in affected
states. Present government regulations
for Texas require that the water at the
mine location be restored to base line
ground-waterquality and the mine sitebe
returnedto its original stateafter solution
mining has ceased(Walsh et al., 1979;
F
Whittingtonand Taylor, 1979).
A L S OI N T H I S] S S U E :
Commercialanalyticallaboratories p.36
p.37
Principal
miningdistricts
p.39
in NewMexico
Turquoise
p.41
Ft.SeldenandLeasburg
p.43
Announcements,publications,abstracts
SOON:
COMING
.
.
.
.
o
plants
oreindicator
Uranium
1859-1936
Jones,miningengineer,
Fayette
Gravitationalore separation
Potashin NewMexico
in NewMexico
Earthquakeactivity
New AAexnc@
GEOLOGY
.
andSorvice
Scionco
Volume 1, Number 3, AuguBt 1979
Edilot' Neila Pedson
publishedqueterlY bY
New M€xicoBurau of Mines& Mineml Resources
a divisionofNev MexicoInstituteofMining & Technology
BOARDOFNEGENTS
Ex Officio
BrtceKitg, Oovernor o! New Mqico
Leonard Delayo, Superinlendenl of Public lutruction
Appointcd
William C. Abbott, 196l-1985,Hobbs
L6 Cilces
Judy Floyd, 1917-1981,
OwenLop€z,Sety/Tt.6,1977-1983, SontoFe
Pres.
1972-l9El,
Cqilsbad
DaveRice,
S@orro
SteveTorres, 196?-1985,
New Mexico Instituteof Mining & Technology
. ord
. . . . . K e n n e t h wF
Pr6idqt.
New MexicoBur€auof Mines& Mineral Resourcc
...FrankE.Kottlowski
Director.
. . . . . . . . . C e o r g e sA, u s t i n
Depu,tDirector.
Burfiu EditoFceologitl . . . . . . . . . . . . Robert lV. Kellcy
Subscriptiore:Issued quilterly, F€bruary, May, August,
November;subrcriptionprie $3.00/yr.
Ediloriol mtter: Contributions of possiblematerial for conissu6 of NMG ile sdcome.
sidqation in furw
Marcrials ronot b€ returned unless accompaniedby
retun postage,Addressinquirid to Neila Pesson, Editor
Ncw Mexico Ceology, New Mexico Bureau of Mines &
Mineral Resources.
Saorro. NM 87801
Cirelalion: l,2N
Priu ler.' University of New Mexico Pdnting Plmt
Bacteriahave recentlyreceivedconsiderableattentionas agentsfor restoration
of in-situ mine operationsleachedwith
ammoniurncarbonatesolutions.The organismsspecificallyconsideredfor this
function areNitrosomonas,which oxidize
ammoniumto nitrite,
ion, and possibleproblemsthat bacteria reducingbacteria in the sedimentsmay
in the formation might createsuchas re- participate in trace element removal.
Theseorganismsreducesulfateto hydroductionin permeability.
gensulfide
Restorationof mining and milling waters
(15)
S O . ' - +l 0 H + * H , S * 4 H ' O
Many organismshave the capacityof
at
binding
by
metals
either
accumulating
the organisms'surfacesor by intracellular using hydrogenor simple organic mole( 1 3 ) uptake of the ions. Likewise, biological culesas energysources.Analysesof sediNH.++3/2 O'*2H+ +H,O+NO,agentscan readily transform metals by ments indicate significantaccumulations
and Nitrobacter, which oxidize nitrite to solubilization, precipitation, valency of uranium and molybdenum.The mechchanges, and conversion to organo- anisms for ion removal have not been
nitrate.
metalliccompounds(Kelly, et al., 1979)' defined, but it is evident from early
and biolog(14) Because
suchtransformationsoccur on a studiesthat both geochemical
NO,-+ l/2 Ou*NOroperative.
likely
are
of
ical
reactions
use
the
geochemically
significantscale,
bacteria has long been considered a
Microbial problernsin
incorporole0
schemefor metal recovery from dilute
uraniumleaching
in-situ
/'
solutionssuch as seawater.Rather than
Thus far only the beneficialuses of
mineral depletionbeing a motivating facin the mineral industry
tor, environmental constraints and microorganisms
but it is apparent
discussed,
have
been
economic conditions were primarily
in
mining practicesis
technology
new
that
I
responsiblefor active developmentof
incidences of
increased
in
resulting
NO:
biological processesfor recovery of
problems
are blaThe
fouling.
metalsfrom dilute solutions.One of the microbial
less
evident,
are
the
causes
obvious,
tantly
most successfulapplicationsof the proanswersare not immediately apcessis the use of algaeto removeboth and the
parent,
solubleand particulatelead from the mill
Mine sites that are leachedwith cartailings of severalmining venturesin the
solutionsand hydrogenperoxide
bonate
"new lead belt" of Missouri (Gale and
experienceplugging. Backsometimes
Wixson, 1977;1979).In one operationa
FIGURE I -Tnr stoLoctcAl NtrRocENcYcLE.
wells revealsthe presence
the
of
flushing
tailingspond allowsheavyparticulatesto
of massive,macroscopicgrowths of miOther bacteriaare capableof denitrifica- settle, and the effluent from the pond
croorganisms.Preliminaryidentifications
tion reactions, i.e., the reduction of passes through a series of shallow
indicate theseorganismsto be common
nitrate to reducednitrogenspecies.Some meanders.Algae are encouragedto grow
of soil bacteria.Somepluggingof mine sites
microbesreducenitrate to gaseousnitro- in themeanderingstream,and analyses
occursthat cannotreadilybe attributedto
gen while othersreducenitrate to nitrous the algaeand aquaticvegetationindicate
either physical or biological factors. In
oxideor ammoniumion. The endproduct that theseagentseffectivelyaccumulateor
suchinstancesit may be necessaryto test
is species
dependent.The energyneedsfor entrapthe heavymetalsreleasedin the effor microbial activity, since these agents
denitrificationcan be an organic energy fluent from the tailings pond. A settling
may be producinggaseswhichcould form
sourcefor most microbesand thiosulfate pond and baffled outlet preventthe algae
an airlock in the formation' Examplesof
or elemental sulfur, a source for the from discharging into the receiving
suchactivity arethe productionof hydroorganism Thiobocillus denitrificans. As stream.Vegetation,identifiedto function gen
sulfide by the sulfate-reducingbacshownin the biologicalnitrogencycleasit effectivelyin this wastewatertreatment,
(reaction 15) or the production of
teria
occursin soil (fig. l), it is feasibleto oxi- include Cladophora, Rhizoclonium, gaseous nitrogen by Thiobscillus dedize ammonium to nitrate and then re- Hydrodictyon, Spirogyro, Potomogeton
nitrificans:
and occasionalbloomsof Oscillatoria.
ducenitrateto a gas.
biological/chemical
A combination
Sorne preliminary researchhas been
5SrO"--| 8NO'- * HuO*
completedon the use of Nitrosomonas treatmentsystemis presentlyoperational
(16)
4N, + 9SO.',-+ H,SO.
and Nitrobscter for uranium mine site in the Grants, New Mexico uranium disrestoration (David Johnson, personal trict for the removalof selenium,molybTo date little is known whY microcommunication).These studies indicate denum,radium, and uranium from mine
organisms sometimes suddenly grow
that biologicalnitrification can occur in wastewater.The system consists of a
abundantly and uncontrollably in the incolumn experimentsusing uranium core seriesof settlingponds to removeheavy
situ uranium leach sites.It may be that
and syntheticground water. It is entirely particulatematter; somewatersare subchemical and physical conditions are
feasiblethat bacteriacould be usedto ox- jectedto an ion exchangeplant to remove
alteredto the point where opportunistic
idize both mobilizedammoniumand ad- uranium.Barium chlorideis subsequently
microbesfind a suitablenichefor prolific
sorbedammoniumto solublenitrate. The addedto precipitatesulfateand radium. growth. Hydrogen peroxide,as the oxiareretainedin threeconnitratecould then be easilyflushedout of The wastewaters
dant for uranium oxidation,is an oxygen
the mine site. There are many factors to secutivealgae ponds before discharge.
carrier and may supPlY the aerobic
be critically examined.Among theseare This wastewatertreatmentsystemis now
environmentneededfor microbial develthe introductionof the nitrifying bacteria under study (C. Brierleyand J. Brierley,
opment. The causativefactors of this
into the formation,the retentionof viabil- unpublished data). It is evident from
situationare as ill-definedas preventative
ity of the bacteriain the in-situ site, the preliminarydata that, althoughalgaeand
Currentlythe only actionbeing
measures.
continued activity of the bacteria, their aquatic vegetation are present, large
IF
ability to oxidize adsorbedammonium populations of anaerobic, sulfateReduced
orgonic
N
inlo glonis/onimols / microbes
NewMexico Geology
August 1979
taken against microbial growth is the
periodic injection of strong oxidizing
agentssuch as chlorine gas. It may be
necessary
to find an antimicrobialagent
that successfullypreventsgrowth, is inexpensive, environmentally acceptable,
and doesn't interfere with the leaching
and uraniumrecoveryprocesses.
uncontrollably proliferating in artificial
environmentscreatedat the leachingsites
and in the uranium recoveryand restoration circuits associatedwith the operations.
Substantialeffort is neededto evaluate
microbial practicesand problemsof the
mining industry. Evaluations must be
comprehensive,
includingnot only the imConclusions
mediateproblemor practice,but the basic
Microorganismscanbe eithera boon or aspectof the situation.A cooperativeefbane to the mining industry. Bacterial fort among many disciplinesis needed,
leaching has a vital niche in the pro- for the solutionsto the problemsare not
duction of copper and uranium from likely to be uniquelybiological.
low-grade ores. Likewise, low-cost
References
cited
energy-conservativetechniques for
recovery of vagrant inorganic con- Beck, J. V., 1967,The role of bacteriain copper
mining operations: Biotechnology and Bioengitaminantsfrom industrialwastewaterare
neering,v. 9, p. 487-497
makingincreasinguseof microbes.
Brierley,C. L., tg'l 4, MolybdeniteJeaching:useof a
Further investigationwill reveal new
high-temperature
microbe: Journal of the LessCommonMetals,v. 36,p.237-247
applicationsof microorganisms
to benefit
in ex1977,Thermophilicmicroorganisms
the uranium industry. The processlikely
in Intraction
from
Developments
of
metals
ores:
to havethe most potentialis the bacterial
dustrialMicrobiology,v. 18,p. 273-284
oxidationof ammoniumion remainingin
1978a,Bacterial leaching: CRC Critical
the formation after in-situ leachingwith
Reviewsin Microbiology,v.6, no. 3,p.207-262
1978b,Biogenicextractionof uranium from
ammoniumcarbonatesolutions.
ores of the Grants region: Metallurgical ApplicaHowever,new technologies
in uranium
tions of BacterialLeachingand RelatedMicrobiomining are evoking problemsnot previlogicalPhenomena,Murr, L. E., Torma, A. E.,
ously associated with this industry.
and Brierley,J. A. (eds.),AcademicPress,New
Opportunisticmicrobesare rapidly and
York, p. 345-362
Directory of
commercial analytical
laboratories in
New Mexico
Types of analyses
Routine chemical assaysinclude both
wet and instrumentalmethods(depending
on preferencesof the individual laboratory) and are analysesof major (l-10090)
andminor (.01-l9o)elements.
Geochemicalassaysinclude analysesof
trace elements in geological materials
(.0001-.0190);
theseare usuallydone by
instrumentalmethods.
Fire ossayis a method of analysis for
gold, silver, and platinum group metals
usingfurnaceheatand dry reagents.
Woter quality analyses include the
chemicaland biologicalanalysesof water
constituentsbut do not include trace contaminants.
Rapid whole-rock analysis is the
analysisof the major and minor oxidesby
atomicabsorption.
Radiometric ossays. pertain to the
measurement
of geologictime by the disintegrationrateof radioactiveelements.
Radiochemicalassaysare chemicalanalysesof radioactivematerials.
August 1979
New Mexico Geology
Commerclal llstlngs
Albuchemist.Inc.
715SanMateoBlvd. NE
Albuquerque,NM 87108
(s0s)268-'t36'7
Routine chemicalassayson soil, water, gasoline,
ore andpaint
AlbuquerqueAssayLaboratory
4l l5 SilverAve. SE
Albuquerque,NM 87108
(5O5)268-5',776
Routine chemicalassayson ores
Rapid whole-rockanalyses
Mineral examinations
Traceanalyses
Geochemicalassay_s
Water -quality onaIy ses
Radiometric assays
Controlsfor EnvironmentalPollution,Inc.
P.O. Box 5351-1925Rosina
SantaFe. NM 87501
(s05)982-9841
Radiochemical analyses
Biological assays
Traceinorganicand organiccontaminants
Water-quality analyses
Pesticideanalyses
CoreLaboratories.Inc.
3428Stanford Dr. NE
Albuquerque,
NM 87104
(sos) 344-0274
Ilater analyses
Uranium analyses
Baseandpreciousmineral assays
Geochemicalassays
Brierley, C. L., and Brierley, J. A., 1973, A
and
thermophilic
microchemoautotrophic
organism isolated from an acid hot spring: Canadian Journal of Microbiology, v. 19, no. 2, p.
l 83-r88
Brierley,C. L., Brierley,J. A., Norris, P. R., and
Kelly, D. P., 1979, Metal-tolerant microorganismsof hot, acid environments:Societyfor
Applied Bacteriology, Technical SeriesPublication No. 14,in press
Brierley,J. A., 1978,Thermophiliciron-oxidizing
bacteriafound in copperleachingdumps:Applied
and EnvironmentalMicrobiology,v. 36, no. 3, p.
523-525
Brierley,J. A., andBrierley,C.L.,1978, Microbial
leaching of copper at ambient and elevated
temperatures: Metallurgical Applications of
Bacterial Leaching and Related Microbiological
Phenomena,Murr, L. E., Torma, A, E., and
Brierley,J. A. (eds.),AcademicPress,New York,
p.477-489
Brierley,J. A., and Lockwood,S. J., 1977,The occurrenceof thermophilic iron-oxidizing bacteria
in a copper leachingfacility: Federationof European Microbiological SocietiesMioobiology Letters,v. 2, p. 163-165
Brock, T. D., Brock, K. M., Belly, R. T., and
Weiss, R. L., 1972,Sulfolobus: a new genusof
sulfur-oxidizingbacterialiving at low pH and high
Archivesof Mikrobiologia,v. 84, p.
temperature:
54-68
Bryner, L. C., and Anderson, R., 1957, Microorganismsin leachingsulfide minerals: lndustrial
Chemistry,v. 49,p. 1721-1724
andEngineering
(continuedon page 40)
EberlineInstrumentCorporation
P.O. Box2108
SantaFe, NM 87501
(50s) 4'71-3232
Radiotion measurements
Radon monitors
Radiochemistry
SilverCity TestingLaboratories,lnc.
505Texas
SilverCity, NM 88061
(505)538-3029
Routine chemicalassayson ores
Fire assays
Custom assays
Prlces and fees
Most commercial laboratories have
three qualities of work: the routine or
preliminary, which is the lowest priced
and is not run in duplicate; a control,
which is medium priced and generallyrun
in duplicate;and an umpire, which is very
exact,usuallya wet methodrun in triplicate.The last methodis the most costly.
In generalthe higher the price, the better
the results.
The New Mexico Bureau of Mines and Mineral
Resources neither vouches for nor recommends the
commercial laboratories listed herein over any other
laboratories. The information was supplied by the
individual laboratories. The list is intended to include all laboratories in this area; any omissions are
by oversight only.
tr
-Lynn A. Brandvold,
Chemist
NMBM&MR