U S Environmental Protection Agencjf
Region 5, Library (PL-12J)
77 West Jackson Boulevard, laA f •*»
Chicago, IL 60604-3590
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The Trouble with
Historic Mine Sites
This metals
deposit on the
wall of a mine
shaft is nearly
pure zinc.
"If we don't understand what is
going on and how the water moves
through the earth, we'll end up
spending a lot more money and
getting a lot less done."
Bruce Stover
Senior Geologist and Project Director
Division of Minerals and Geology
Colorado Department of Natural Resources
Investigate,
Investigate:
The Importance of
Detective Work
Historic hardrock mining activities in the West
have created hundreds of thousands of geological
disturbances. Drainage and runoff from mine
sites impact water quality in streams throughout
the Rocky Mountain states. While cleanup of
mine sites is a high priority, the sheer number
and geographic distribution of these disturbed
areas make addressing them a formidable task.
Traditional metals mining usually involves
digging tunnels and adits to reach lodes of
mineral-rich ore. Rock is removed from
deep within the earth, and milled to
extract desired minerals. When the ore is
exhausted, miners move on leaving behind
finely-ground tailings and waste rock above
ground, and tunnels underground.
Such mining activities expose part of the
earth's crust to water, oxygen, and bacteria.
Layers of metals-rich rock that have been
underground become oxidized and chemically
altered. When water flows through and over
the newly-disturbed material, metals that were
once locked within rock can dissolve in the
water. Zinc, iron, cadmium, copper, lead—
metals that are toxic to aquatic life and can
damage human health—end up contaminating
surface waters and ground water.
The activities that created the mine workings,
residual wastes, and other impacts to the envi-
ronment at inactive and abandoned mine sites
are generally poorly documented. Consequently,
little or no useful information is available as
the reclamation specialist steps onto the site to
determine specific water quality impacts, their
origins, and remediation strategies.
PUP
•I
V
.—artWSUgBBZ-""
'• ^IPPwiPPll^
Top:The eerie effects of windblown tailings near the former Mary Murphy
Mine and Mill in Colorado. Bottom Left: Tailings and the remains of
historic mine workings exhibit the characteristic reddish-brown color of
iron oxide leaching. Bottom Right: Blocked by mine waste dumped in the
stream channel, the flow in French Creek was reduced to ponding near
the former Weilington-Oro Mine near Breckenridge, Colorado.
Since every mine site is unique, using "off-the-
shelf" characterization strategies can lead to an
improper or incomplete understanding. Remedial
actions based on a partial picture of a site may
overlook important contaminant sources or
pathways, resulting in no improvement to
water quality. With limited financial resources
available to address mine sites, failure of remedi-
ation will only be tolerated to a limited extent.
Adequate resources and time must be dedicated
to extensive site characterization before remedial
activities are proposed and undertaken. Charac-
terization includes five steps: 1) reconstructing
pre-mining conditions, 2) inventorying what
has been deposited above ground, 3) mapping
what has occurred underground, 4) monitoring
the movement of water, and 5) estimating the
impacts of mining disturbances.
Far Left: Gathering data on water from a mine pond.
Top Right: Collecting ground water from a well for
sampling purposes. Bottom Right: Water quality analysis
can sometimes be performed on site, from the back of a
truck equipped with laboratory equipment.
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Taking a Closer Look:
Two Colorado Mine Sites Shed Light on Future Cleanup Projects
Staft and managers involved in cleaning up
mining-related sites haw begun to realize that
traditional site remediation can be tremen-
dously expensive, running into the millions of
dollars. There are simply not sufficient funds to
approach every site that needs cleanup in the
tiaditional manner. I his realization led the
teams working on Chalk (leek and French
Gulch to look for more cost-effective ways to
meet environmental goals
To tackle the immense task oi characterization
at these two historic mine sites in Colorado, it
was critical to have a team representing a
diverse but complementary mix of expertise
and experience. The teams working on these
sites include geologists, mining engineers,
hydrogeologists, biologists, water quality
engineers, mined land specialists, and public
relations specialists. The ability and willingness
of these experts to work together was a definite
factor in the eunent successes of the projects
Tlie map on fxige 8 stoivs the location^ of the
Chalk deck iimi Fremh Gii/i/i s/'fcs.
Chalk Creek:
Getting Our Feet Wet
In 1980, the Colorado Division of Wildlife's
Chalk Gifts lish Rearing Unit experienced
widespread death among its fmgerling tiout.
Located on the lower reaches ot Chalk Creek,
the unit uses water fiom the creek. This fish
kill prompted the Coloiado Department of
Public Health and the Dniionment (C Dl'HL)
to conduct watei quality sampling along Chalk
Creek Results revealed elevated levels of zinc
and cadmium. 'Ihe highest concentrations of
Looking south from the top of Chrysolite Mountain toward
the Chalk Creek site—a vast expanse of barren hillside
covered by tailings.
the metals occurred neai the former Maiy
Murphy Mill site, upstream from the fish
rearing unit
In 1990, the Chalk (.reek site was selected tot
Colorado's Nonpoint Source Program. 'Ihe
Division ot Minerals and Geology (DV1G)
within Colorado's Department of Natuial
Resources took the initial lead in the cleanup.
Other piimary partners include CDPHF, 1 PA's
Region 8, the U.S. Bureau ot Mines, the
Colorado Division of \\ildhte, and pmate
businesses and \olunteer oigamzations.
Chalk Geek received high prionU toi remedia-
tion foi two major reasons.
1) Its extreme level ot impact to fish
habitat in Chalk Creek.
2) Its contribution to watei quality
degradation in the Arkansas River
Ground and Surface Water
Investigations Used to
Characterize the Site
In order to determine contaminant sources,
the project team established a network of
ground water monitoring wells at the site and
surface water monitoring stations along Chalk
Cieek. Under an annual monitoring program,
members of the team collected surface and
ground water samples in spring, summer, and
fall. These samples established baseline infor-
mation for the area.
Initial water quality sampling and geophysical
investigations identified three primary sources
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for metals and sediment loadings: 1) mill tail-
ings piles, 2) discharge from a prominent adit
(the Golf Tunnel), and 3) some unknown
source.
With this knowledge, the team established
ambitious objectives for improving local water
quality:
1) 50-100% reduction in metals and
suspended sediment loadings.
2) Sufficient reductions in instrcarn metal
coaccntrations to allow art increase
in salmonid abundance in South
Chalk Creek.
3) Reduction of chronic metal stress to
aquatic organisms in South Chalk Creek.
4) Elimination or significant reduction of
acute lethality to fingerling trout at
Chalk Cliffs Fish Rearing Unit.
In order to address the determined sources of
contamination, two major remedial activities
were conducted during the summer and tall of
1991. First, five tailings piles were consolidated
into one, and then covered with waste rock
from the site to reduce the potential for further
erosion. Second, the Golf Tunnel was unplugged,
with drainage from the adit redirected through
a settling pond.
Disappointing Results Underscore
Importance of Full Characterization
Water quality in Chalk Creek did not improve
after these remediation activities were completed.
Why9 Several possibilities exist. Fiist, metals-
laden ground water is suspected as a previously
unidentified source of contamination.
Remediation focused solely on surface watei
GEOLOGY AND WELL COMPLETION DIAGRAMS
1992 Chalk Creek Drilling Project
After a constructed wooden barrier deteriorated, tailings once
retained by It drifted directly into Chalk Creek
WELL COMPLETION
Filter Sand
Bentomte Seal
Clean Fill
Cement Grout
GEOLOGV
Glacial/Alluvial
Gravels
Disseminated
Metal Suphide
Zone in Monzomte
Quartz-Monzonite
Bedrock
Note bedrock Total Depth: 17ft
intenal in
uas core-dulled
Total Depth- 23ft
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sources. Second, metals from mine operations
have been washing into Chalk Creek for more
than 100 years. Regardless of remediation
activities taken today, metals accumulated
along the creek bottom could contribute to
contamination for years to come.
Continued problems of metals
leaching may also be due in
part to residual tailings
left behind during the
consolidation effort—
these are now expos.ed to
mobilization through leaching
and erosion. Seeps were not
taken into consideration when
planning lor the consolidation
efforts. Nor were wetlands at the site
properly studied prior to remediation
decisions. Once hailed as natural passive
water treatment systems, wetlands may
act as metal sinks during the growing
season only to release stored metals during
fall and winter.
The major problem in the case of Chalk Creek
is that characterization efforts came too late.
The reclamation concept was already in place
when the project team began investigations.
In addition, the site proved to be much more
complex than any of the participants had
anticipated.
Future actions at Chalk Creek will focus on
continued site characterization in an effort to
better understand the pathways for ground
water movement. This will include drilling
additional ground water monitoring wells and
conducting tracer studies. The key to solving
the water quality problems at Chalk Creek lies
in a more thorough understanding of the site's
geochemistry and hydrology.
-ft*
MAP OF THE OUTER PART
OF THE GOLF TUNNEL
Mary Murphy Mine, Chalk Creek, Colorado
EXPLANATION
Sets & Lagging
Strike & Dip of Joint
Strike of Vertical Joint
Mount Princeton
Quartz-Monzomte
Injection Hole
Sulphide Vein
Portal Elevation 10,345ft
Tunnel Bearing S 37 E A
Scale Approx 7/8" = 100 ft N
Unplugging the Golf Tunnel adit did
contribute to dec reused zinc loadings
to Chalk (jeek fiom that aica of the
site. Yet it's not really understood
what mechanism contiols this change.
h it bemuse /me oxides are allowed to
precipitate by aeration? This is an
important experiment that could help
to solve similai problems at other
mine sites.
Samples of core drilling taken from a fault zone at the French Gulch site.
From top to bottom, notice how the rock becomes increasingly fractured.
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French Gulch:
Implementing the Lessons
Learned from Chalk Creek
Beginning high in the mountains, French
Creek flows near the City of Breckenndge and
into the Blue River through a prime tourist and
recreation area. In 1989, concern over water
quality in the area was raised when fingerling
trout released into the Blue Rivei downstream
of French Creek died The Coloiado Department
ot Public Health and the Fnvironment CDPHF)
conducted extensive water qualit) sampling in
response to this fish kill.
Results showed acutely toxic conditions in a
stretch of Trench Creek from the site of the
Wellington-Oro Mine to the Blue River Metals
loadings ha\e completely eliminated the trout
population in this stretch of water, and have
seveieh reduced tiout populations in the Blue
River for an undetermined distance
These sampling studies determined the
\Vellington-Oio Mine to he the primary cause
ot wUer quality impacts to the French Creek
and Blue River drainages, [he Irench Gulch
site was selected for the Colorado Nonpoint
Source (NFS) program tor three primary leasons:
1; Its significant impact on the Blue River
trout population.
2) Its high public \isihility,
.5) Its negatne economic impact on
Summit County and Breckenndge.
Fhe .State ol Colorado's Division ot Minerals
and Geology (DMG) assumed responsibility for
implementation and management of the
I rend: Gukh NTS project. Other primary
participants in the pioject include. CDPHF,
FTA's Region 8, the U S. Bureau ot Mines, and
Summit County. Initial objectives set in this
case were less ambitious than ior Chalk Creek.
Rather than setting specific targets roi remedia-
tion, these objectives remain broad and focus
on chaiactcrzation.
Objectives:
1) Establish baseline physical, chemical,
and biological conditions (pre-
jemefliation)
2) Identify primary toxic metals sources,
transport, and fate through physical,
chemical, and biological sampling.
3) Evaluate remedial alternatives tor
possible isolation, removal, containment,
and treatment of priority sources.
4) Reduce heavy metals loading from the
French Gulch project site to levels
which would not produce acute or
chronic toxicity to aquatic life in the
Blue River.
5) Minimize contaminant loadings to the
Blue River during project remediation
activities.
6) Document the development and
benefits of the French Gulch project
and estab'ish a long-term water quality
and aquatic life monitoring and contin-
gency plan that will assure design
integrity of the French Gulch site aiea
of the watershed
Laily sampling at the French Gulch site revealed
three primary souices of metals loadings'
1) Saturated tailings adjacent to the
stream. Some tailings below the water
table. Seepage from the tailings rust-
eoloied.
2) Discharge ot mine water thiough
fractuies in shale bedrock into the
alluvium.
3) Runoff from roaster tines and mine
waste rock piles exposed to normal
precipitation. F.xtremely acidic pH
levels measured in samples ot runoff
horn these piles
Further study of these sources led to several
intensified characterization studv actions
Mine Pool Discharge Source
I Isolate mine discharge, . ^ Sig
- 1 shut off flow | """" imp
f JGW table stays high ||
improvement Gw table lowe
!•'
1 Flows and chemistry 1 ' '
I Hows/chemistry "
^^^
WfflffiW, I
^&r I
•UjiJjiSj Saturated Mill Tailings Sources
Rcfrr>nstC|»~t ^ Wat
French Gutch • ~ sign
?
nficantWQ LJ Highfl
rovement j| metal
1 r
rs Low flows, minor
1
t
er table lowers
ficant WQ improvement
1 ^±\S^Lnrr — ^Relocate.ailinesoofo.AVFH
-L
i '
1 Some WQ impraverr
^ Complete or significar
" WQ improvement
AVF=Alluvial Valley Floor GW= Ground Water WQ=Water Quality
-------
Tuxicit)' oj dissolved metals in
l-rench Creek and the Blue River
was evaluated using (eriodiiplmui
in 48-hour mute toxicity tests.
Little 01 mi mo/fu/i'lr was found
upstream of the \\'ellmgton-0n>
Mine site. I mm the site to Freihh
('.reek's conflueihe with the Blue
River, liowevei, lOO'ih mortality
was obsem'd. One mile down-
stream from the confluence, again
no tnnte toxiiit) wn~> found. The
site team also eundiicted habitat
testing using L'l'A's Rapid Kioussess-
nient 1'iotocols, with similai results
Riologkal tools stiji us these ilk'
pioving tremendoiislv useful til
mine sites in testing hypotheses
mid establishing piionlies lor
fuithei stud\
Grouting Shaft No. 3 at French Gulch
ntL^
Treatment plant I
neutralization approach I
Evaluate need to
continue Phase 2
i
i
i
I—..
Surface Storm Runoff
Relocate, isolate wastes
U
Significant WQ
improvement
Install run-on/run off
cpnirois to remaining
site areas
Run feaeftate
collection to Phase 1
treatment •
Run storm/surface
flows to Phase 1
treatment
] Minor or no WQ improvement I
I Conduct drilling and tracer tests |
| New sources identified |
No new sources
identified-evaluate
isolation success
I Numerous/complex
sources
Simple 1 or 2 additional
sources
I Seal/isolate new sources
(Direct upstream mine
pool treatment approach
Expand site or
develop new technology
PHASED PROJECT
APPROACH PLAN,
FRENCH GULCH
Phased approach assumes each metals
source is a significant contributor.
(Best Management Practices
alternatives are in shaded boxes.)
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Characterization Efforts and
Their Effects
During operation of the Wellington-Oro Mill,
tailings were deposited directly into the French
Creek drainage. Thus, the tailing disposal area
became hydraulically connected to the alluvium
and the flow in French Creek. Over the years,
placer tailings and mine tailings effectively
dammed the creek. In fact, placer dredge tails
created artificially high water levels all around
the mine site.
Efforts to restore the creek's flow by removing
tailings from the stream bed succeeded in
dropping water levels in the tailings, and seepage
volume decreased. However, the elevation of
the reconstructed French Creek drainage is still
above the lowest level of tailings, and some
tailings remain saturated. The ultimate effects
of this remediation activity on water quality
have not yet been determined.
The French Gulch site from a nearby ridgetop.
Notice the ski runs of Breckenridge Ski Resort
in the background.
A significant portion of the underground mine
workings remains flooded. Because of the high
water table, it was determined that this "mine
pool" flows directly into the alluvium. The key
to keeping contaminated mine pool water out
of the creek lies in discovering this exact
hydraulic connection, and then determining
the best remediation method.
When members of the French Gulch team
suspected Shaft No. 3 to be a problem, they
developed a plan to seal the shaft. The objectives
of this action were:
•»- To eliminate seepage of mine water into
the alluvium.
*- To better quantify and characterize the
discharge from the mine pool.
Shaft No. 3 was grouted, and then a pipe was
inserted to allow for drainage of-mine pool
water to the surface. The team also constructed
a drainage ditch on the surface for collected
mine water. However, the water level in Shaft
No. 3 did not rise, meaning that this shaft is
not the only pathway ot mine pool water to
the alluvium.
Further investigation revealed numerous
hydraulic connections via fractures in the rock
and highly-fractured, subsidence zones above
the mine workings. The 11-10 fault, the largest
in the area, extends from ground level through
all levels of the mine, including those below
the water table.
In order to address contamination from
precipitation through roaster fines and mine
waste rock, a plan was developed to encapsulate
these waste piles. The encapsulation unit would
be capped and lined, with a leachate collection
and treatment system. Though planned and
designed, this activity has been temporarily
suspended until further data are gathered.
Questions about whether to proceed include
projected costs and the amount of metals
loading that would ultimately be controlled
by this action.
Future Characterization Activities
Continued work at the French Gulch site will
focus on characterization. Planned activities
include:
i*- Drilling additional ground water
monitoring wells.
^- Continuing ground water sampling and
tracer studies.
^- Mapping previously-undefined features.
^- Conducting geophysical surveys.
i»- Sampling all waste piles.
^- Undertaking further investigation of
the 11-10 fault.
Several future remedial activities have been dis-
cussed and may be undertaken, depending on
the outcome of the characterization efforts
outlined above. These are:
t*- Recontouring the site with runoff
directed to collection and necessary
treatment.
*- Leaving waste piles in place and
managing runoff, and construction of
a subsurface barrier.
i*- Returning waste rock to the mine.
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Experience as Teacher
Probably the most important.lesson learned
from cleanup efforts at Chalk Creek and
French Gulch is that characterization and
remediation ot mine sites are much more com-
plex than imagined. The amount and level ot
scientific information needed to characterise a
pathway (e g., ground water flow to a stream) are
magnitudes greatei than had been expected—
planned foi, budgeted for, scheduled for As a
result, these projects have taken longer to
understand and ultimately remediate than
was origmalh thought.
Pressures for a Quick Fix Come from
Many Directions
While cleanup ot mine sites demands a
thoughtful, step-by step approach, a host of
constraints can hinder this. Inteicsted parties
and the geneial public typically call lor taking
swift action to improve water quality \et sites
like Chalk Creek and French Gulch aie
extiemeh complex Observing and quantity
ing the impacts ot contaminants ma\ be quite
straightforward, but determining exact pollutant
sources is much more unoKed
In addition to these obstacles, limited financial
resources make extensive site characterization
difficult. And decisions are often driven by
tunding sources available. "I he Nonpoint Source
Program, for example, requiies development
and implementation of Best Management
Practices to mitigate identified impacts. Unlike
other types of nonpoint source projects, though,
mine sites tend to lequire more complex
solutions.
Down the Road: Tips for Other
Mine Sites
*~ Metals accumulate in the topsoil or
peat layer due to absorption by organics
in these layers. Further characterization
ot the organic materials that are
naturally-occurring on site (such as in
wetlands or peat bogs) is necessary.
»- lake caie when recommending
hydraulic controls (e.g., tunnel or adit
pluggmgsl as a final site icmedy. 1 In-
cidence suggests that this type of
solution is tempoiaiv at best. Instead,
tiy to understand the hvdrologic
s\ stem at a site and deal with the water
that is theie.
i/c\t i>ti^e)
PARTIAL RECONSTRUCTION OF UNDERGROUND WORKINGS
Wellington-Oro Mine, French Gulch NPS Site, Colorado
Seen on a single plane here,
these tunnels and adits actually
exist on eight different levels.
Three-dimensional modeling
can be a critical step in the
characterization process.
Knowledge Gained:
Chalk Creek and
French Gulch as
Practical Models
FRENCH GULCH
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Location of Study Sites
French Gulch and Chalk Creek, Colorado
i
(Tips continued from previous page)
^- Go\ ernmcntal agencies need to learn
to work together as a team. Pooling
resources and expertise yields
better results.
*~ At some sites, obvious point source
discharges can be remediated.
Hioreactors using sulfate-reducing
bacteria substrates (SRB's) are
showing some promise as one means
of treating mine water discharges
containing heavy metals at acid
conditions. These treatment systems
may need to be housed in struCtuies to
perform more optimally in harsh
weather conditions.
t^~ Site remediation should focus more on
impacts to the aquatic ecosystem and
less on other endpoints, such as human
health impacts. If one understands the
impacts that a site and remediation
actions have on ecosystems and their
sensitive aquatic life, then cleanup
levels necessary to protect human
health will usually be exceeded.
A Better Toolbox: What's Needed for
More Effective Site Characterization
and Remediation
^- A standardized screening process
(written methodology) that gives
direction on how to characterize or
assess sites. We need the right data to
calculate an accurate metals balance.
^- A committed leader. The person/agency
in charge must have a commitment to
seeing the project through, and be
willing to ask for help when necessary.
^- A team approach, with the right mix of
the right people No one person has the
background or experience to understand
all of the complex processes going on at
abandoned mine sites.
^- Personnel trained in the specifics of
metals mining reclamation, including:
water chemistry, ground water hydro-
geology, stability of metals species, and
metals mobilization.
^- Institutional flexibility to approach
mining sites somewhat experimentally.
i - o
© Printed on Recycled Paper
-------
Chalk Creek and French Gulch are typical of
the many inactive and abandoned mining and
ore processing sites in the Rocky Mountain West.
Neither site has produced the catastrophic
environmental damage that might place it on the
Superfund priority list. Yet from the perspective
of the Colorado Department of Public Health
and Environment, these two sites—like hundreds
of others across the state—pose definite threats.
As such, these sites were recognized as possible
test cases for using experimental characterization
techniques at mine sites.
To tackle the task of characterization at these
two sites, specialists from several complementary
disciplines came together to combine
their expertise. The teams approached
Chalk Creek and French Gulch with
few preconceptions about the
geologic, hydrologic, and physical
systems operating at each site.
Water quality improvement goals
at Chalk Creek and French Gulch
have not yet been achieved. Yet
Far Right: Water draining from a mine tunnel in the Chalk
Creek area runs bright red with dissolved metals.
Top Left: Just upstream from a fish hatchery intake gate,
the stream bottom reveals the tell-tale whitish-gray coloring
of tailings. Bottom Left: A moonscape caused by mine
tailings contrasts starkly with the natural alpine vegetation.
these two sites have been extremely valuable lab-
oratories for agencies and reclamation specialists
involved in characterization and remediation
efforts. Ongoing work will help to better under-
stand and solve the impacts to water quality at
the sites.
Precipitation
Dredge Tail Dredge Tail
Tailings Pond
No. 3 Level
Shale Bedrock
Precipitation *
Siam Tunnel
Cross Section
through French Gulch
at Wellington-Oro Mine,
High Flow Conditions
Potential Sources of
Heavy Metals Contamination
Q Mill tailings in alluvium,
saturated by French Creek
Q Precipitation leaches metals
from mine and mill waste to
water table
@ Mine pool from Wellington-
Oro complex drains to
French Creek alluvium
Porphyry Bedrock
KEY
No. 4 Level
No. 5 Level
No. 6-7 Levels
T =
I Alluvium
I Porphyry Bedrock
I Shale Bedrock
I Waste Rock
I Roaster Fines
I Dredge Tails
Flooded Workings
Precipitation
Direction of Seepage
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Lessons Learned
from Chalk Creek
and French Gulch
• Sites can be far more
complex than they appear—
hydrologically, geologically,
and physically. Obvious
metals sources may not be
the only ones contributing to
water quality problems.
• Without appropriate levels of
human resources and the ability to commit
them in a concentrated effort, mine sites can
take an extremely long time to characterize.
• It is nearly impossible to plan work in
advance because it's a "learn as you go" process.
• After remediation activities, water
quality may actually get worse before
it gets better. Follow-up work is
essential to achieve objectives.
• Even with a total cleanup, it could
take decades to see complete restora-
tion of water quality at a site. Additional
causes of contamination are likely to
become apparent only after cleanup of obvious
sources.
• Securing funding for characterization work
continues to be a challenge.
The Road Map:
Steps for Understanding
Effective Site
Characterization
and Cleanup
"Using the tools currently available
for use in mine site characterization
feels like conducting an autopsy
with a butter knife. We need more
sophisticated, more reliable tools.
Experience together with better tools
is the winning combination."
Carol Russell
Environmental Scientist
Environmental Protection Agency, Region 8
Into the Future
COLORADO
DEPARTMENT OF
NATURAL
RESOURCES
Produced by the U S. Environmental
Protection Agency, Region 8, with
the Colorado Department of Natural
Resources, Division of Minerals and
Geology. For additional copies or
information, call (303) 293-1603 or
(800)227-8917.
• Ask—and answer—the hard questions
before beginning cleanup at any site.
1) Why should this site be cleaned up?
2) Will it make measurable differences in
water quality to clean up the site and
leave other nearby sources as they are?
3) How much time and money will the
cleanup take?
• When attempting cleanup of a mine site,
pay attention to available technology, institu-
tional commitment, and financial resources.
Failure to manage any one of these could derail
good effort in the others.
• Set achievable goals and objectives.
Remember: one size does not fit all.
• Do a good job of analyzing the data collected.
Use information on flows, concentrations,
water levels, and contamination to forecast
trends or see anomalies.
• Follow up once surface reclamation is com-
pleted. Which techniques were successful?
Which were not? Why?
Initially, EPA and other agencies approached
mine site investigations in a relatively simplistic
manner. Experience has proven, however, that
a minimalist approach does not provide the
complete story. Reaching a thorough under-
standing of what causes water quality problems
at a mine site can take significant resources,
money, and time. Yet many people—from agency
managers to the general public—continue to
expect cheaper, quicker fixes than are possible
to deliver. Solving problems related to mine
sites must be considered a long-term effort.
In addition, the overall structure must allow for
experimentation and learning. Instead of
regarding an activity that doesn't work as a
"failure," it must be seen as a valuable lesson to
be transferred to other situations. An important
tenet of the scientific process remains true: You
Top: Revegetated wetland area, formerly covered by tailings
and barren of any life. Bottom Lett: Fly fishing and rafting
on the Arkansas River in Colorado—reminders of why
cleaning up abandoned mine sites Is so important. Good
water quality makes possible many uses of our Western
streams. Bottom Right: Drilling a ground water well near
the French Gulch site.
don't always prove a theory by conducting
experiments; rather, you disprove false hypotheses.
Many of the West's inactive and abandoned
mine sites have been around for a hundred
years or more. Five, ten, even twenty years of
remediation efforts probably won't undo all
the damage done. Nevertheless, it's important
to remember why we continue to try: for clean
water. If not today, then perhaps tomorrow.
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