ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF ENFORCEMENT
EPA-330/2-77-021
Evaluation of
Settleable Solids Removal
Alaska Gold Placer Mines
(JULY 11-21, 1977]
NATIONAL ENFORCEMENT INVESTIGATIONS CENTER
DENVER, COLORADO
AND
ALASKA OPERATIONS OFFICE
rtto STjr
REGION X - ANCHORAGE, ALASKA >> ^. *.
SEPTEMBER 1977
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CONTENTS
I INTRODUCTION 1
II SUMMARY AND CONCLUSIONS 3
III STUDY PROCEDURES 5
IV STUDY FINDINGS 7
APPENDIX
Typical Permit for Alaska Placer Mine
TABLES
1 Major Equipment Used
During Alaska Survey 6
2 Alaska Gold Placer Mine
Sites Visited 6
3 Results of Analyses, Alaska Gold
Placer Mines 8
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I. INTRODUCTION
Pursuant to the 1972 Amendments to the Federal Water Pollution
Control Act, the Environmental Protection Agency (EPA), Region X has
issued National Pollutant Discharge Elimination System (NPDES) permits
to the gold placer miners operating in the State of Alaska. At the
present time, there are about 200 such active mines.
The permits, which are identical for all the mines, require that,
beginning May 1, 1977 and lasting through the expiration date of the
permit, the miner must either:
"a. Provide settling pond(s) which are designed to contain the
maximum volume of process water used during any one day's
operation. Permittee shall design single and/or multiple
ponds with channeling, diversions, etc., to enable routing of
all uncontaminated waters around such treatment systems and
also to prevent the washout of settling ponds resulting from
normal high water runoff. Choice of this alternative requires
no monitoring."
or
"b. Provide treatment of process wastes such that the following
effluent limitations be achieved. The maximum daily concen-
tration of settleable solids from the mining operation shall
be 0.2 milliliter of solids per liter of effluent. This shall
be measured by subtracting the value of settleable solids
obtained above the intake structure from the value of settle-
able solids obtained from the effluent stream. The permittee
shall monitor his influent and effluent on a monthly basis
with grab samples."
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Also, beginning May 1, 1977, "the permittee must not cause a
turbidity level greater than 25 JTU (Jackson Turbidity Units) above
natural turbidity in the receiving stream at a point measured 500 ft
downstream of the final discharge."
The permit also requires a) that all mined areas shall be left "in
a condition which shall not cause additional degradation to the receiving
waters over those resulting from normal natural causes of erosion and/or
runoff," and b) that the "Permittee shall provide safe passage of fish
around or through the active mining area in streams which support or
have supported an indigenous fish population. This includes the operation
of safe intake structures and protection from high solids in the discharge.1
These permits have been challenged by both environmentalists who
contend that they are not stringent enough and by miners who contend
that they are too stringent. Some environmentalists believe that the
permits should specify no discharge from a mine site (complete recycle).
Some miners believe that they should be allowed to operate with no
restrictions. An adjudicatory hearing to resolve these problems has
been set to convene in Anchorage on October 18, 1977.
On July 13, 1977, EPA's Region X requested that the National
Enforcement Investigations Center (NEIC) develop additional information
to support the settleable solids limitation. The NEIC was specifically
requested to visit several mine sites in Alaska and demonstrate the
achievability of the 0.2 ml/1 settleable solids limitation.
Appreciation is extended to personnel of the Alaska Fish and Game
Commission and the Alaska Department of the Environment, who provided
valuable assistance to the EPA inspection team.
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II. SUMMARY AND CONCLUSIONS
Over twenty individual mine sites were visited during the survey
period. Only ten of these were using water to remove overburden or
recover gold in a sluice box during the visit. Others were either
removing overburden mechanically (tractor), had equipment breakdown, or
did not have enough water to operate. At the ten sites in operation,
samples of influent water, in-process streams and final effluent were
taken and analyzed for temperature, pH, conductivity, settleable solids,
turbidity, total suspended solids, iron, arsenic and mercury.
Most, although not all, of the miners visited had received EPA
permits. Of the ten mines sampled, five (Mines 1, 2, 4, 11, 15) were
meeting the settleable solids limitation and two (Mines 11, 15) were
meeting the turbidity limitation. Only two of the five (Mines 11, 15)
were meeting the settleable solids limitation as a result of settling
ponds. The effluent from Mine No. 1 received no settling but the solids
being discharged were so fine that they did not settle under conditions
of the settleable solids test. The effluent from Mine No. 2 went
through two settling ponds in series but short circuiting was so severe
that little settling was achieved. Settleable solids were removed as
the water flowed in a shallow stream about 0.9 mile before joining the
receiving water. At Mine No. 4, short circuiting through two ponds in
series again prevented attainment of the settleable solids limitation.
After the effluent left the second settling pond, it percolated through
a berm of old tailings before joining the receiving water. The settle-
able solids were removed during this percolation.
Achievement of the turbidity limitation is primarily a function of
the relative volumes of the effluent discharge and receiving streams.
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Sedimentation as practiced at the sites visited did not effectively
remove the fine particles causing high turbidities.
In all cases, it appears that the settleable solids limitation of
0.2 ml/1 can be met by the provision of 4 hours or less of quiescent
settling in a pond having a minimum depth of 5 feet. The settleable
solids limitation can also be met by percolation of the wastewater
through tailings existing at the site.
Data indicate that, although sedimentation adequate to achieve the
0.2 ml/1 limitation will reduce the other parameters measured, the
effluents will still contain high concentrations of turbidity, total
suspended solids, iron and arsenic relative to the intake supply.
Discussions with miners and observations during the survey indicate
that complete recycle of process water should be feasible if the settleable
solids limitation is achieved. This may result in some decrease in the
efficiency of gold recovery but would considerably reduce or eliminate
the burden of total suspended solids, turbidity, arsenic and iron presently
being added to the receiving waters.
Several miners visited had experience with, or were experimenting
with, grizzlies, wobblers or other devices to remove large rocks prior
to the sluice box. It was reported that this would result in a decrease
in water consumption of up to 75%, thus decreasing the size of pond
necessary to remove settleable solids and the cost of recycling pond
effluent if this procedure was adopted.
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III. STUDY PROCEDURES
The limitation of 0.2 ml/1 settleable solids in the placer mining
permits had been set by EPA's Anchorage Operations Office on the basis
of observations made at placer mine site inspections, literature reviews
and discussions with placer mining experts.
To develop additional information to support the settleable solids
limitation contained in the permit, a survey was conducted that incor-
porated sampling at all sites visited that were operating. Grab samples
were taken of a) the water supply, b) the wastewater leaving the sluice
box, c) the wastewater after sedimentation (if any), and d) the receiving
stream 500 ft below the discharge. Measurements at the site included
temperature, pH, conductivity, settleable solids and turbidity.
Selected samples were also collected and returned to the NEIC
laboratory for determination of the amount of total suspended solids,
iron, mercury and arsenic added to the receiving waters.
Table 1 shows the major pieces of equipment used by the survey
crew. Table 2 lists the sites visited at which information was developed
Measurements of temperature, pH and conductivity were made at the mine
site. Analyses for settleable solids and turbidity were conducted using
Imhoff cones and a turbidimeter, respectively.
Settleable solids analyses were conducted in accordance with Part
I.C.4 of the permit [Appendix]. Total suspended solids, iron and arsenic
concentrations were determined according to approved procedures as set
forth in 40 CFR Part 136, Guidelines Establishing Test Procedures for
the Analysis of Pollutants. Mercury was determined by the method of El-
Awady, Miller and Carter, Analytical Chemistry, 48, 110 (1976).
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Table 1
MJOR EQUIPMENT USED DURING ALASKA SURVEY
pH Meters - Leeds and Northrup Model 7417
Conductivity Meters - Beckman with low range probe
Turbidimeter - Hach Model 2100 adapted to run off 12-volt wet battery
by use of Sola Constant Voltage Transformer Model
No. 20-22-125
Imhoff Cones
Table 2
ALASKA GOLD PLACER MINE SITES VISITED
July 12 - 21, 1977
Date Mine No. Receiving Stream
12
12
13
14
15
15
15
16
16
17
17
17
17
18
20
20
21
21
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
Bird Creek
Cache Creek
Big Willow Creek
Livengood Creek
Ruth Creek
Lillian Creek
Olive Creek
Pearl Creek
Faith Creek
Charity Creek
Faith Creek
Gold Dust Creek
Miller Creek
Deadwood Creek
Caribou Creek
Valdez Creek
Cache Creek
Big Willow Creek
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IV. STUDY FINDINGS
The results of the testing [Table 3] and observations made at the
mining sites demonstrated that the settleable solids content of placer
mining wastes can be reduced to below 0.2 ml/1 by providing a quiescent
settling period for the wastewater or by percolating the wastewater
through tailings that were present in abundance at most of the mines
visited.
In the settleable solids determination procedure, a sample of the
wastewater is poured into a 1-liter conical container and allowed to
settle quiescently for 1 hour. The volume of solids that settles in
this time period is then determined. Reason dictates that, if the water
analyzed by this procedure had previously been subjected to a quiescent
settling period, the settleable solids will have been removed and none
will settle during the determination.
Since no settling rate tests were conducted on the mine effluents,
it is not possible to predict the exact amount of time needed to meet
the settleable solids limitation. Engineering judgement indicates that
a settling time of 4 hours in a well-designed settling pond (no short
circuiting) will produce an effluent that will meet the desired settle-
able solids limitation. A minimum depth of 5 feet should be provided to
reduce scouring of the solids that have settled.
A discussion of the operations at each of the mines listed in
Table 2 follows.
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Table J
RKS'JLTS OF ANALYZES, AUr-M COLD PLACER HIKES
Mine Ho.
and
Sample Location
Receiving
Stream
1.
2.
4.
•
8.
9.
11,
Bird
Creek
Cache
Creek
Liven-
good
Creek
Pearl
Creek
Faith
Creek
7/16/77
.Faith
Creek
7/17/77
Bird Creek upstream
Mine Influent
Mine Effluent
Bird Creek 500 ft.
downstream
Peters Creek upstream
of Bird Creek
Falls Creek
(source of water)
Sluice box effluent
Effluent from second
settling pond
in series
Cache Creek upstream
Cuddy Effluent before
mixing wi th
Cache Creek
Cache Creek 600 ft.
downstream
Livengood Creek upstream
Intake to No. 1 Sluice
Influent to first
treatment pond
Effluent from second
pond
Livengood Creek 500 ft.
below discharge
Discharge to stream
after percolation
thru berm
Intake to Giant
Influent to Fond
After settling and
dilution
Intake water
Faith Creek 500 ft.
below discharge
Influent to first
settling pond
Effluent from last
settling pond
Intake to sluice
Influent to first
settling pond
Effluent from last
settling pond
Faith Creek 500 ft.
below discharge
Temp.
"C
11
11
12
15
12
20
18
24
18
10
19
8.5
8.5
10.5
12
10.5
18
8
8
10
10
pH Conductivity
7.
7.
7.
7.
7.
7.
7.
7.
7.
8.
4
3
5
4
8
4
4
5
1
3
7.4
7.
8.
7.
8.
8.
7.
7.
8.
8.
3
2
9
6
2
4
3
5
7
umho/cm
60
<50
<50
59
62
62
60
60
68
67
480
65
110
105
80
115
105
100
105
101
89
Settleable Turbidity
Solids
ml/1 NTU
1.2
1.5
0.15 190
0.05 89
0.47
15
13 840
15 1,200
* 6.3
0.15 110
Tr 18
* 30
39
1.8 7,200
140
140
Tr
5.600
* 28
0.15 170
10 830
1.3 740
* 23
1.7 370
Tr 130
0 12
Total
Suspended Iron Arsenic
Solids
mg/1 mg/1 ug/1
1 0.1 <10
2 0.4 11
520 50 91
300 14 50
1 <0.1 <10
58 2.0 <10
9.000 280 1,200
4,000 130 560
10 0.7 <10
230 13 12
21 1.4 <10
14 3.4 <10
120 3.4 <10
24,000
170 10 50
4 0.5 14
61,000
580 28 14
23 1.7 29
410 25 60
6,200
1,900
17 2.2 26
1,130
220 19 57
10
Mercury
,9/1
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
<1 .0
<1 .0
<0.2
<0.2
<0.2
<0.2
<0.2
0.5
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
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Table 3 (C.-ntinu-:d)
RES'JLTS OF AHALYSES, AUSKA COLD PLACES HIUES
Mine No.
and
Receiving
Stream
13. Miller
Creek
15. Caribou
Creek
17. Cache
Creek
18. Big
Wi 1 1 ow
Creek
Sample Location Temp, pll Conductivity
°C umho/cm
Intake to sluice 12 7.2 205
Pond Influent 12 7.1 200
Pond Effluent 12 7.5 220
Marmot h Creek 500 ft.
downstream 13 7.4 210
Intake to sluice
Discharge to Caribou
Creek
Caribou Creek 500 ft.
downstream
Influent to Settling
Pond
Pond Influent after
1 hour settl ing
Intake water
Influent to settling pond
Effluent from settling
pond
Cache Creek 500 ft.
downstream
Pond Inlet after
1 hour settl ing
Intake to sluice
Influent to settl ing
pond
Effluent from
settling pond
B1g Wil low Creek
500 ft. downstream
Cottonwood Creek 6CO ft.
below Junction with
Big Wil low Creek
Pond Inlet after 1 hour
settling
Scttleable
Solids
ml/1
*
Tr
Tr
17
Tr
•*
1.6
0.4
Tr
0
*
1.5
0.3
0.15
0
Total
Turbidity Suspended
Solids
NTU mg/1
12 3
7,000 33,000
5,200 22,000
6,700 26,000
0.8 4
79 120
8.3 6
6.2 17
1,300 1,420
320 230
3.7 7
1,800 2,080
2,000 2,350
600
Iron Arsenic Mercury
mg/1 pg/1 ug/l
0.2 <10 <0.2
440 2,500 <1.0
<0.1 16 <0.2
12 31 <0.2
0.9 14 <0.2
1.3 12 <0.2
62 280 <0.2
<0.2
0.4 <10 <0.2
101 270 <0.2
<0.2
* Settleable solids content of intake aster va3 assigned to be zero. This uas obvious from appearance of uater.
Tr = trace anoioit less trim 0.1 ml/1.
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10
MINE NO. 1
Water for this operation was furnished by a series of ditches in
the mountains feeding a head box. The water fed two giants (water
cannons) which were removing 50 to 60 ft of overburden. The sluice box
had not yet been set up and was not planned to be in use until mid-
August. The water from this operation flowed over 100 ft vertically to
Bird Creek through a narrow canyon. There were no settling ponds but
the mine effluent contained only 0.15 ml/1 settleable solids because the
material being washed out was very fine and did not show up in the
settleable solids test. The overburden material being washed down
appeared to be non-organic in nature but it resulted in a significant
increase in the total suspended solids, turbidity, iron and arsenic
content of Bird Creek and in Peters Creek into which Bird Creek flowed.
MINE NO. 2
The source of water for this operation was Falls Creek and about
one-third of the total volume of the creek was being used. The water
was transported from the creek by ditch into a small holding pond and
then pumped by a 3,300 gpm centrifugal pump to a giant which was forcing
overburden and pay dirt through a sluice box. A small Caterpillar
tractor was being used to remove large rocks that were building up at
the end of the sluice box. The tractor had also been used to construct
two settling ponds through which the sluice discharge flowed. However,
these ponds were experiencing short circuiting and the total residence
time in both ponds, as determined by dye tests, was about 10 minutes.
The effluent from the second pond, which had a settleable solids content
of 15 ml/1 flowed about 0.9 mi. before entering Cache Creek. During
this flow, it went through about fifteen sets of ripples and pools and
had a total travel time of about 72 minutes. This allowed settling and
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11
reduction of the settleable solids to 0.15 ml/1 before it entered Cache
Creek. The flow rate of Cache Creek was large relative to the mine
output so the effect on the receiving water was smaller than experienced
at Mine No. 1.
The analytical results of samples taken at Mine No. 2 [Table 3]
indicate that, when settleable solids are reduced, the other parameters
are likewise reduced. It is likely that most of the iron and arsenic in
the mine discharges are associated with the suspended solids and that
effective removal of suspended solids would reduce the turbidity, iron
and arsenic content of the discharges.
MINE NO. 3
The source of water for this mine was Big Willow Creek which was
impounded and then flowed by gravity to a pump feeding a sluice box.
The sluice box was fed pay dirt by a front-end loader and there were one
or two Caterpillar tractors available for pushing the pay dirt to the
sluice box area. On the day prior to our visit, a front-end loader
overturned, crushing the suction pipe to the pumps. The mine was there-
fore not operating during our visit.
MINE NO. 4
This operation had an upper and a lower mining site. The upper
mining site was fed by water from a trench in the mountains above the
operation. The effluent from the first sluice box then went into a
settling pond which was the source of water for the lower mining opera-
tion. The final effluent returned to this first pond, went through a
second pond and then percolated through a bank of discarded tailings,
eventually reaching Livengood Creek. The first pond was providing essen-
tially no settling as there was severe short circuiting of the wastewater
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12
to the second pond. The lower placer mine was not in operation at the
time of our visit. The effluent from the ponds themselves did not meet
the settleable solids limitation but percolation through tailings did
accomplish this.
This mine used essentially all of Livengood Creek in its operations
and therefore its discharge had an appreciable effect on the total
suspended solids, iron and arsenic content of the receiving water. This
mining operation was the only one sampled that resulted in a measurable
increase in mercury in the receiving water.
MINE NO. 5
This mine on Ruth Creek was not in operation during the time of our
visit but indications were that it would have been one of the most
effective in settleable solids removal visited during the survey. The
canyon configuration was such that the miner had been able to build a
substantial water reservoir upstream of his operation and two large
sedimentation ponds downstream of the operation. This mine was not yet
in operation because not enough water had collected in the reservoir to
allow sluicing. The mine operator stated that when one of the settling
ponds is abandoned, gravel and rock would be moved back on top of the
silt to stabilize the area. The ponds were up to 27 ft deep, very well
constructed and had overflow pipes to prevent washout.
MINE NO. 6
Operation at this mine was just shutting down as we arrived. The
water supply is Lillian Creek and water is in scarce supply. The mine
had been operating for only 75 minutes that day. The water supply is
principally recycled water from a pond downstream of the operation.
After 75 minutes of operation, this pond had become so high in suspended
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13
solids that, according to the operator, the efficiency of gold removal
had decreased. There were two other ponds further downstream containing
high quality water but the operator stated that the economics of pumping
this water back up for use were prohibitive.
MINE NO. 7
This was a small operation that had recently been purchased by
three brothers and a partner. They had a small front-end loader/back
hoe combination that they were using. They reported that thus far this
year they had sluiced about 40 yds of dirt. Water was in short supply
and the pay dirt was low in gold content so they were trying to sell the
mine.
MINE NO. 8
This was a hydraulic or water cannon operation in which the op-
erator was removing 50 to 60 ft of overburden which was very rich in ice
lenses. The equipment consisted of two giants, one medium-sized tractor,
and a drag line for feeding an elevated sluice. At the time of our
visit, the operator was removing overburden with the giants and the
actual sluicing operation had not yet begun. It was difficult at this
operation to tell where the effluent from the mining operation met the
receiving stream. There were several "ponds" downstream but none of
them appeared to be effectively removing settleable solids. They were
silted in and the water velocity was not decreased. The total suspended
solids and iron contents of the receiving stream were raised appreciably.
MINE NO. 9
Homestake and Charity Creeks were used to fill the reservoir
feeding this mine site. The water flowed by gravity to the sluice box
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and the sluice box discharge joined Faith Creek. Just prior to our
visit, the line between the reservoir and the sluice box had ruptured,
allowing excessive water flow that destroyed the downstream settling
ponds that had been constructed.
There were over ten of these ponds, each one relatively small. The
operation was fed by a front-end loader which was using material pushed
into a pile by a tractor. Sampling this day showed very poor removal of
settleable solids and all other parameters measured.
MINE NO. 10
This mine was upstream of Mine No. 9 and used Homestake Creek as a
source of water filling a reservoir. The effluent from the operation
flowed into Charity Creek. This mine was not in operation during the
time of our visit and was producing no wastewater. The operator was
removing overburden by use of a tractor.
MINE NO. 11
This is the same mine as Mine No. 9 but was sampled after the
settling ponds had been repaired overnight. These ponds, even though
small, were effective and removed settleable solids to a trace amount.
It would be more effective to have a fewer number of larger settling
ponds. However, this operation did indicate that it is not difficult to
achieve the settleable solids limitation. Even with effective sedimen-
tation, however, the mine resulted in the addition of considerable
amounts of turbidity, total suspended solids, iron and arsenic to the
receiving stream.
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15
MINE NO. 12
This mine was on Gold Dust Creek and used a front-end loader to
feed the sluicing operation. However, on the day of our visit, the
Bureau of Land Management had appropriated their tractor to fight a fire
and they were therefore not in operation.
MINE NO. 13
This miner was providing a good portion of the water for the
sluice box by recirculating from a small pool just off the end of the
sluice box. The water being recirculated was quite high in suspended
solids. The water supply was from Miller Creek and discharged into
Mammoth Creek. Although there appeared to be a possibility of building
a settling pond (15 ft difference in elevation between sluice box and
receiving water), there were no effective ponds on the day of the visit.
Analyses showed that appreciable amounts of turbidity, total suspended
solids, arsenic and iron were being added to the receiving water.
MINE NO. 14
This mine is located on Deadwood Creek; it was not in operation
during the time of our visit because of a breakdown of equipment. This
operation was evaluating a "wobbler." This device removes the larger
size rock (greater than 1-1/2 in) before the material enters the sluice
box. It is reported that this cuts the water use requirement by 75% and
shortens the box length needed. Other operations, we were told, had
used "grizzlies" and other devices for removing the larger rocks before
they went to the sluice box. This appears to be an effective way of
reducing water consumption and pond requirements as well as man-power
requirements. A "stacker" is used to transport large rocks removed by
the wobbler to waste piles.
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16
MINE NO. 15
This mine utilizes water from Caribou Creek and discharges effluent
to the same creek. The miner used a rock separation device so that
rocks bigger than 1 in. were screened out. The operation was highly
automated and could be operated by one man. The washing, screening, and
sluicing operations were on wheels and could be moved as the source of
the pay dirt changed. This operation had three settling ponds in
series with an estimated residence time of about 4 hours. Even though
these ponds were very effective in removing settleable solids, the
turbidity, total suspended solids, iron and arsenic content of the
discharge were considerably higher than those of the water supply.
MINE NO. 16
This operation on Valdez Creek had not yet started but two sedi-
mentation ponds in series had been constructed and they looked quite
adequate to remove settleable solids to the desired level.
MINE NO. 17
This operation got its water supply from Cache Creek and returned
the effluent to Cache Creek. One tractor was used to feed pay dirt to
the sluice box and one for removing the tailings from downstream of the
box. The operation had a sedimentation pond that looked large enough in
size but appeared to be experiencing short circuiting. It was estimated
that the residence time was about ten minutes but no dye studies were
conducted. The settleable solids were reduced to 0.4 ml/1 by the
settling pond but, as seen at other mines, settling was not effective in
reducing the other parameters to low levels.
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17
MINE NO. 18
This was a revisit to Mine No. 3, which had been shut down during
our earlier visit because of a crushed pump suction line. The mine was
in operation during this visit and had two relatively large settling
ponds but short circuiting prevented them from meeting the discharge
settleable solids limitations. The influent wastewater stream could be
seen going directly from the pond inlet to the pond outlet.
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APPENDIX
TYPICAL PERMIT FOR ALASKA PLACER MINE
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Permit No.
Application No.
AUTHORIZATION TO DISCHARGE UNDER THE
NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM
In compliance with the provisions of the Federal Water Pollution
Control Act, as amended, (33 U.S.C. S 1251 et seq; the "Act"),
is authorized to discharge from a facility located near
to receiving waters named
in accordance with effluent limitations, monitoring requirements and
other conditions set forth in Parts I and II, hereof.
This permit shall become effective on
This permit and the authorization to discharge shall expire at
midnight,
Signed this day of
Acting Director, Enforcement Division
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PART I
Page 2 of 9
Permit Mo.:
A. EFFLUENT LIMITATIONS
_1. Commencing the beginning of the 1977 mining season, the
permittee will take whatever reasonable steps are appropriate to
reduce the amount of organic and non-organic solids reaching navi-
gable waters (navigable waters are defined as the water of the United
States). This includes leaving all mined areas in a condition which
shall not cause additional degradation to the receiving waters over
those resulting from normal natural causes of erosion and/or runoff.
2. Permittee shall provide safe passage of fish around or
through the active mining area in streams which support or have
supported an indigenous fish population. This includes the operation
of safe intake structures and protection from high solids in the
discharge.
3. Beginning on May 1, 1977 and lasting through the expiration
date, the permittee must not cause a turbidity level greater than
25 JTU (Jackson Turbidity Units) above natural turbidity in the re-
ceiving stream at a point measured 500 feet downstream of the final
discharge.
4. Beginning on flay 1, 1977 and lasting through the expiration
date, the permittee must as a minimum meet one of the following con-
ditions:
a. Provide settling pond(s) which are designed to contain
the maximum volume of process water used during any one day's
operation. Permittee shall design single and/or multiple ponds
with channeling, diversions, etc., to enable routing of all un-
contaminated waters around such treatment systems and also to
prevent the washout of settling ponds resulting from normal high
water runoff. Choice of this alternative requires no monitoring.
b. Provide treatment of process wastes such that the
following effluent limitations be achieved. The maximum daily
concentration of settleable solids from the mining operation
shall be 0.2 mill "Miter of solids per liter of effluent. This
shall be measured by subtracting the value of settleable solids
obtained above the intake structure from the value of settleable
solids obtained from the effluent stream. The permittee shall
monitor his influent and effluent on a monthly basis with grab
samples.
5. All activities in developing and operating treatment systems
and diversions shall be done in a manner so as to minimize any water
quality problems in the receiving water.
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PART I
Page 3 of 9
Permit No.:
B. SCHEDULE OF COMPLIANCE
1. The permittee shall achieve compliance with the effluent limita-
tions specified for discharges in accordance with the following schedule:
a. By March 31, 1977 the permittee shall submit to the
Environmental Protection Agency and the Alaska Department of Environmental
Conservation the following:
1. The method chosen to meet condition Part I.A.4.
2. A diagram of the mining area identifying the source of
water, sluicing area, nearest stream or river, and general drainage. Also
identify water usage and locations, if any, or existing settling ponds.
3. General description of mining techniques and/or method
of stripping overburden which affects the discharge.
4. Estimated quantity of water to be discharged; average
and maximum amounts. Is water recycled?
5. Describe the condition of the receiving water both
above and below the mining operation; include pertinent information such
as the existence of mining activities upstream which may be affecting the
quality of the receiving water, glacial conditions, condition of stream bed,
presence of fish, etc. Picture aids are encouraged for the above purposes.
6. A list of any chemicals or additives which may be
added to the discharge in any manner.
b. By May 1, 1977 achieve conditions of Part I.A.4.
c. By March 31, 1978 and annually thereafter, the permittee
shall submit an operating plan providing layouts, methods, etc. that will
be used to comply with conditions of Part I.A. Such information as area
to be stripped, area to be mined, diversions of streams, locations of
existing and future settling ponds and point of final discharge should be
included. The permittee shall identify technique he will use to prevent
the discharge of solids (overburden, gravel, silts, etc.) from reaching
the navigable waters. The Director, Enforcement Division may, upon review
of said plan, require additional explanation of any or all of the items not
adequately covered by the plan. This may take the form of requiring limited
monitoring for turbidity, settleable solids, suspended solids, and/or any
other parameter of special concern to the Director, Enforcement Division
towards protection of the receiving water.
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PART I
Page 4 of 9
Permit No.:
C. MONITORING AND REPORTING
If the permittee elects to comply with the 0.2 ml/1 settleable solids
limit in condition Part I.A.4.D., the following shall apply:
1 . Representative Sampling
Samples and measurements taken as required herein shall be
representative of the volume and nature of the monitored discharge.
2. Moni toring
Monitoring settleable solids shall occur once per month and
shall consist of two samples; one in the effluent stream at the point
of discharge and the other in the receiving water above the intake structure.
3. Reporting
Monitoring results obtained during the previous season's operation
shall be submitted at the conclusion of each mining season or no later than
November 1 of each year.
All reports required in this permit shall be submitted to the
Environmental Protection Agency, Alaska Operations Office, and the
Alaska Department of Environmental Conservation at the following addresses:
Alaska Operations Office
Environmental Protection Agency
605 West 4th Avenue, Room G-66
Anchorage, Alaska 99501
Department of Environmental Conservation
State of Alaska
Pouch 0
Juneau, Alaska 99801
U. S. Environmental Protection Agency
Region X
1200 Sixth Avenue
Seattle, Washington 98101
Attn: Water Compliance Evaluation Section M/S 521
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PART I
Page 5 of 9
Permit No.:
4. Test Procedures
Test procedures for the analysis of pollutants shall conform
to regulations published pursuant to Section 304(g) of the Act, under
which such procedures may be required. The procedure for testing for
settleable solids using an Imhoff cone is as follows:
Fill an Imhoff cone to the liter mark with a thoroughly mixed
sample. Settle for 45 minutes, gently stir the sides of the cone with
a rod or by spinning, settle 15 minutes longer, and record the volume
of settleable matter in the cone as mini liter of solids per liter of
effluent.
5. Recording of_ Results
For each measurement or sample taken pursuant to the requirements
of this permit, the permittee shall record the following information:
a. The exact place, date, and time of sampling;
b. The dates the analyses were performed;
c. The person(s) who performed the analysis;
d. The analytical techniques or methods used; and
e. The results of all required analysis.
6. Additional Monitoring by Permittee
If the permittee monitors any pollutant at the location(s)
designated herein more frequently than required by this permit, using
approved analytical methods as specified above, the results of such
monitoring shall be included in the calculation and reporting of the
values required in the discharge monitoring report. Such increased
frequency shall also be indicated.
7. Records Retention
All records and information resulting from the monitoring
activities required by this permit including all records of analyses
performed and calibration and maintenance of instrumentation and
recordings from continuous monitoring instrumentation shall be retained
for a minimum of three (3) years, or longer if requested by the
Director, Enforcement Division or the Alaska Department of Environmental
Conservation.
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Page 6 of 9
PART II
Permit No.:
A. MANAGEMENT REQUIREMENTS
1. Change j_n_ Discharge
All discharges authorized herein shall be consistent with the
terms and conditions of this permit. The discharge of any pollutant
identified in this permit more frequently than or at a level in excess
of that authorized shall constitute a violation of the permit. Any
anticipated facility expansions, production increases, or process modifi-
cations which will result in new, different, or increased discharges of
pollutants must be reported by submission of a new NPDES application or,
if such changes will not violate the effluent limitations specified in
this permit, by notice to the permit issuing authority of such changes.
Following such notice, the permit may be modified to specify and limit
any pollutants not previously limited.
2. Noncompliance Notification
If, for any reason, the permittee does not comply with or will
be unable to comply with any daily limitations specified in this permit,
the permittee shall provide the Director, Enforcement Division and the
State with the following information, in writing, within fifteen (15) days
of becoming aware of such condition:
a. A description of the discharge and reason for noncompliance;
and
b. The period of noncompliance, including dates and times; or
if not corrected, the anticipated time the noncompliance is expected to
continue, and steps being taken to reduce, eliminate and prevent recurrence
of the noncomplying discharge or other alternate steps taken to limit the
discharge of pollutants.
3. Facilities Operation
The permittee shall at all times maintain in good working order
and operate as efficiently as possible all treatment or control facilities
or systems installed or used by the permittee to achieve compliance with
the terms and conditions of this permit.
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PART II
Page 7 of 9
Permit No.:
4. Adverse Impact
The permittee shall take all reasonable steps to minimize any
adverse impact to navigable waters resulting from noncompliance with
any effluent limitations specified in this permit, including such
accelerated or additional monitoring as necessary to determine the
nature and impact of the noncomplying discharge.
5. Bypassing
Any diversion from or bypass of facilities necessary to maintain
compliance with the terms and conditions of this permit is prohibited,
except (i) where unavoidable to prevent loss of life or severe property
damage, or (ii) where excessive storm drainage or runoff would damage any
facilities necessary for compliance with the effluent limitations and
prohibitions of this permit. The permittee shall notify the Director,
Enforcement Division and the State of each such diversion or bypass by
submitting in writing an explanation within fifteen (15) days of the
reported bypass.
6. Removed Substances
Solids, sludges, filter backwash, or other pollutants removed
from or resulting from treatment or control of wastewaters shall be
disposed of in a manner such as to prevent any pollutant from such
materials from entering navigable waters.
B. RESPONSIBILITIES
1.
iht of Entn
The permittee shall allow the Commissioner of the Alaska Department
of Environmental Conservation, the Director, Enforcement Division, and/or
their authorized representatives, upon the presentation of credentials:
a. To enter upon the permittee's premises where an effluent
source is located or in which any records are required to be kept under
the terms and conditions of this permit; and
b. At reasonable times to have access to and copy any records
required to be kept under the terms and conditions of this permit; to
inspect any monitoring equipment or monitoring method required in this
permit; and to sample any discharge of pollutants.
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PART II
Page 8 of 9
Permit No.:
2. Transfer of Ownership or Control
In the event of any change in control or ownership of facilities
from which the authorized discharges emanate, the permittee shall notify
the succeeding owner or controller of the existence of this permit by
letter, a copy of which shall be forwarded to the Director, Enforcement
Division and the Alaska Department of Environmental Conservation.
3. Availability of_ Reports
Except for data determined to be confidential under Section 308
of the Act, all reports prepared in accordance with the terms of this
permit shall be available for public inspection at the offices of the
Alaska Department of Environmental Conservation and the Director, Enforcement
Division. As required by the Act, effluent data shall not be considered
confidential. Knowingly making a false statement on any such report may result
in the imposition of criminal penalties as provided for in Section 309 of the
Act.
4. Permit Modification
After notice and opportunity for a hearing, this permit may be
modified, suspended, or revoked in whole or in part during its term for
cause including, but not limited to, the following:
a. Violation of any terms or conditions of this permit;
b. Obtaining this permit by misrepresentation or failure to
disclose fully all relevant facts; or
c. A change in any condition that requires either a temporary
or permanent reduction or elimination of the authorized discharge.
5. Toxic Pollutants
Notwithstanding Part II, B-4 above, if a toxic effluent standard
or prohibition (including any schedule of compliance specified in such
effluent standard or prohibition) is established under Section 307(a) of
the Act for a toxic pollutant which is present in the discharge and such
standard or prohibition is more stringent than any limitation for such
pollutant in this permit, this permit shall be revised or modified in
accordance with the toxic effluent standard or prohibition and the permittee
so notified.
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PART II
Page 9 of 9
Permit No.:
6. Civil and Criminal Liability
Except as provided in permit conditions on "Bypassing"
(Part II, A-5), nothing in this permit shall be construed to relieve
the permittee from civil or criminal penalties for noncompliance.
7. Oil and Hazardous Substance Liability
Nothing in this permit shall be construed to preclude the
institution of any legal action or relieve the permittee from any
responsibilities, liabilities, or penalties to which the permittee
is or may be subject under Section 311 of the Act.
8. State Laws
Nothing in this permit shall be construed to preclude the
institution of any legal action or relieve the permittee from any
responsibilities, liabilities, or penalties established pursuant to
any applicable State law or regulation under authority preserved by
Section 510 of the Act.
9. Property Rights
The issuance of this permit does not convey any property
rights in either real or personal property, or any exclusive privileges,
nor does it authorize any injury to private property or any invasion of
personal rights, nor any infringement of Federal, State or local laws
or regulations.
10. Severability
The provisions of this permit are severable, and if any pro-
vision of this permit, or the application of any provision of this permit
to any circumstance, is held invalid, the application of such provision
to other circumstances, and the remainder of this permit, shall not be
affected thereby.
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Environmental Protection Agency
Office of Enforcement
EPA-330/2-77-021
EVALUATION OF SETTLEABLE SOLIDS REMOVAL
ALASKA GOLD PLACER MINES
(July 11-21, 1977)
September 1977
National Enforcement Investigations Center
Denver, Colorado
and
Alaska Operations Office
Region X - Anchorage, Alaska
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