United States
                    Environmental Protection
                    Agency

                    Research and Development
 Environmental Research
 Laboratory
 Gulf Breeze FL 32561
EPA-600/S3-84-067  July 1984
SEPA         Project  Summary
                    Acute  Toxicity  of  Eight
                    Laboratory-Prepared  Generic
                    Drilling  Fluids to  Mysids
                    (Mysidopsis bahia)
                    T.W. Duke, P.R. Parrish, R.M. Montgomery, S.D. Macauley, J.M.
                    Macauley, and G.M. Cripe
                      Acute toxicity tests were conducted
                    at U.S.  Environmental Protection
                    Agency (EPA) Environmental Research
                    Laboratories, Gulf Breeze, Florida, and
                    Narragansett, Rhode Island, with eight
                    laboratory-prepared generic drilling
                    fluids  (also called muds) and mysids
                    (Mysidopsis bahia). The test material was
                    the suspended particulate phase (SPP) of
                    each drilling fluid. Toxicity of the SPP
                    ranged from a 96-hour LC50 (the concen-
                    tration lethal to 50% of the test animals
                    after 96 hours of exposure) of 2.7% for a
                    KCI polymer mud to 65.4% for a lightly
                    treated lignosulfonate mud. No median
                    effect (50% mortality) was observed in
                    three drilling fluids — a non-dispersed
                    mud, a spud mud, and a saltwater-fresh-
                    water gel mud.
                      Two of the generic drilling fluids to
                    which  mineral oil had been purposely
                    added were also tested at Gulf Breeze.
                    The addition of the mineral oil, even at a
                    concentration as low as 1 %, dramatically
                    increased the acute toxicity of both fluids
                    to mysids.
                      This Project Summary was developed
                    by EPA's Environmental Research
                    Laboratory. Gulf Breeze,  FL, to an-
                    nounce key findings of the research pro-
                    ject that is fully documented in a
                    separate  report of the same title (see
                    Project Report ordering information at
                    back).

                    introduction
                      EPA  has permitted the discharge  of
                    eight drilling mud types into U.S. Outer
Continental Shelf waters (EPA, 1983)
under the National Pollutant Discharge
Elimination System (NPDES). This research
project was initiated at the Gulf Breeze
Laboratory to determine the acute toxicity
of these eight generic drilling fluids (Table
1) to representative saltwater crustaceans
(Mysidopsis bahia). The tests were
requested by EPA's Effluent Guidelines
Division, Office of Water Regulations and
Standards, and were conducted according
to  methodology  prescribed Two of the
drilling fluids  were  tested at the Nar-
ragansett Laboratory to confirm the valid-
ity of the tests conducted at Gulf Breeze.
Two of the fluids that had been purposely
contaminated with mineral  oil were
tested at Gulf Breeze to  determine the
toxicity of this additive in  representative
drilling fluids
Methods
  Test methods followed those proposed
by Petrazzuolo (1983) with the following
exceptions.
  (1) Natural seawater was used instead
of artificial seawater, at Gulf Breeze, the
natural seawater  was pumped  from
Santa  Rosa Sound and filtered through
sand  and a 5-micrometer  fiber filter;
salinity was controlled at 20±2 parts per
thousand by the addition of deioni2ed
water, and temperature was controlled by
a commercial chiller;
  (2)  5±1-day-old mysids  were  used
instead of 4+1-day-old mysids;

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 Table 1.    Source and Reported Composition of Eight Generic Drilling Fluids Received at U S EPA, Gulf Breeze, Florida
 Drilling Fluid
 Source
                                                                                           Composition
 Component
                                                                             Concentration
EPA-83-001.
KCI Polymer Mud
EPA-83-002,

Sea water
Lignosulfonate Mud
Chromalloy
IMCO Services
EPA-83-003.
Lime Mud
Hughes
EPA -83-004.
Non-dispersed mud
Newpark Drilling Fluids
KCI
Dnspac (Super-Lot
X-C Polymer
Barite
Starch
Seawater

Attapulgite

Chrome Lignosulfonate
Lignite
Polyanionic Cellulose
Caustic
Barite

Seawater

Bentonite
Lime
Barite
Chrome Lignosulfonate
Caustic
Lignite
Distilled water

Bentonite
Acrylic Polymer (for
suspension)
Acrylic Polymer (for
fluid loss control)
Barite
Deionized Water
          50 0  grams (g)
               0.5  g
               1.0  g
             283.2  g
               2.0  g
       257 6 milliliters (ml)

       30.0   pounds per barrel
     (ppbbl)
             15.0  ppbbl
             10.0  ppbbl
             0.25 ppbbl
          TopH 10.5-11.0
To bring mud weight to 17-18 pounds
          per gallon (ppg)
            As needed

             20.06 g
              5.01  g
            281.81  g
             15.04 g
               1.00 g
              8.02 g
            257.04  ml

             13.0  ppbbl
             0.5  ppbbl

             0.25 ppbbl

           190.7  ppbbl
           299.6  ppbbl
EPA-83-005.
Spud mud
 EPA-83-O06,
 Sea wa ter/Fresh water
 Gel Mud
EPA-83-007,
Lightly Treated
Lignosulfonate Mud
 EPA-83-008,
 Freshwater
 Lignosulfonate Mud
                              NL Baroid
                              Milchem
Magobar Dresser
                              Dowel/
 Bentonite
 Lime
 Barite
 Seawater/Freshwater
 Caustic

 Bentonite
 Polyanionic Cellulose
 Sodium Carboxymethyl
 Cellulose
 Barite
 Sodium Hydroxide
 Seawater/Freshwater.  1:1

 Bentonite
 Chrome Lignosulfonate
 Lignite
 Soda Ash
 Carboxymethyl Cellulose
 Barite

 Bentonite
 Chrome Lignosulfonate
 Lignite
 Carboxymethyl Cellulose
 Sodium Bicarbonate
 Barite
 Deionized Water
             12.5  ppbbl
              0.5  ppbbl
             50.0  ppbbl
               1.0 bbl
             To pH 10.0

             20.0  ppbbl
              0.50 ppbbl

              0.25 ppbbl
             20.0  ppbbl
             To pH 9.5
             As needed

             20.0  ppbbl
              5.0  ppbbl
              3.0  ppbbl
              1.0  ppbbl
              0.5  ppbbl
            178.5  ppbbl

               15.0  g
               15.0  g
               10.0  g
                0.25 g
                1.0  g
             487.0  g
             187.0  ml

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  (3) Test mixtures were aerated, and
  (4) For the mineral oil tests, glassware
was washed  with  petroleum  ether  to
assure removal of the oil.
  To prepare the suspended paniculate
phase of each drilling fluid, 800 milliliters
of chilled seawater were added to a  2-
hter Erlenmeyer flask. Then, 200 milliliters
of the well-stirred drilling fluid were
added to the flask. More seawater (1,000
milliliters) was added to bring the contents
of the flask to the 2-liter mark. This 1 -part
fluid:9-part seawater  slurry was placed
on  a magnetic stirrer  and mixed for  at
least 5  minutes.  The pH and  dissolved
oxygen were measured and, if necessary,
adjusted.
  The number of animals exposed to a
drilling fluid and the number of replicates
varied. For range-finding tests,  10 mysids
were added to each of 4 concentrations
and a  control,  none of which  was
replicated. For definitive tests, 20 mysids
were added to each of 5 concentrations
and 3  replications  were  maintained; a
seawater control and a reference toxicant
(positive control)  were also maintained.
The reference  toxicant was sodium lauryl
sulfate.
Results and Discussion

Generic Drilling Fluids
  The range of toxicity of eight laboratory-
prepared generic drilling fluids to mysids
was considerable. The 96-hour LC50's
were from 2.7% suspended paniculate
phase  (fluid #1) to 65.4% (fluid #7). An
LC50 could not be calculated for three
fluids — #4, #5, and #6 — because no
median effect (50% mortality)  occurred
(Table  2). It should be noted that these
tests were not designed to identify the
constituents in drilling fluid  #1  that
caused it to be more toxic than the other
fluids.
  The  response  of  the  mysids  to the
reference toxicant, sodium lauryl sulfate,
showed that the test animal populations
were in suitable condition for the toxicity
tests. In  five tests, the 96-hour LC50's
were from 3.4 ppm to 7.5 ppm. These are
in accord with the  literature and with
unpublished data from Gulf Breeze and a
commercial testing  laboratory. The
reference toxicant LC50's  obtained  at
Gulf Breeze and Narragansett  were
similar, even though the brood stocks and
natural seawater were different.
  The  interlaboratory agreement of
drilling fluid test  data from  Gulf Breeze
and  Narragansett was equally good. To
assure the validity of the Gulf Breeze
tests, two of the drilling 'fluids (#1 and #5)
were tested  at  Narragansett The 96-
hour LC50 for fluid #1 was almost exactly
the same at both laboratories (Table 3)
The results of the tests with fluid #5 were
similar: Narragansett observed no mor-
tality in 100% suspended particulate
phase,  whereas  Gulf  Breeze recorded
12%  mortality in  that concentration.
Considering  the nature of the  test
material, this represents  a  more than
satisfactory duplication of  test results.

Mineral Oil-Contaminated
Drilling Fluids
  The  addition of mineral oil to generic
drilling fluids #2 and  #8  dramatically
increased their acute toxicity to mysids.
When  1% mineral oil was  added, the 96-
hour LC50 changed from 51.6% to 13.4%
for fluid #2 and from 29.3% to 7.1% for
fluid #8. Addition of 5% and 10% mineral
oil further increased toxicity (Table 4).
  There was a  significant negative
correlation between mineral oil content
 Table 2.    Results of Acute Toxicity Tests with Eight Generic Drilling Fluids and Mysids fMysidopsis bahia/ The Tests Were Conducted at U.S. EPA,
           Gulf Breeze, Florida, During August-September 1983
Drilling Range-finding Test
Fluid (median effect)
#7 >1%<10%SPPC
#2 >50%1O% <50% SPP
#4 No median effect
in 100% SPP
#5 1OO% SPP
#6 No median effect
in 10O% SPP
#7 >50% <100% SPP
#8 >10% <50% SPP
Definitive Test"
(96 -h LC50 & 95% CL>
2 7% SPP
(2.5-2.9)
51. 6% SPP
(47.2-56.5)
16. 3% SPP
(12.4-20 2)
12% mortality in
100% SPP
12% mortality in
100% SPP
20% mortality in
100% SPP
65.4% SPP
(54.4-80.4)
29. 3% SPP
(27.2-31 5)
Positive Contror
(96-h LC50 & 95% CL)
5 8 ppm"
(4.3-7.6)
7.5 ppm
(6.9-8. 1)
7.3 ppm
(6.6-8.1)
3.4 ppm
(2.8-4.1)
Same as for # 7
6.0 ppm
(5.4-6.6)
Same as for #6
Same as for #3
Definitive Test"
(96-h LC50 & 95% CL)
3.3% SPP
(3 0-3.5)
62. 1% SPP
(58.3-65.4)
20.3% SPP
(15.8-24.3)
—
—
—
68.2% SPP
(55.0-87.4)
30.0% SPP
(27.7-32.3)
 "Calculations by moving average, no correction for control mortality unless stated.

 "Calculations by SAS®probit; correction for all control mortality. Analyses performed by R. Clifton Bailey, U.S. EPA Program Integration and Evaluation
 Staff, WH-586, Office of Water Regulations and Standards, Washington DC 20460

 cThe suspended particulate phase (SPP) was prepared by mixing 1 part drilling fluid with 9 parts seawater. Therefore, these values should be multiplied
 by 0.1 in order to relate the 1:9 dilution tested to the SPP the whole drilling fluid.
 "Corrected for 13% control mortality

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   and the  96-hour  LC50 for  each fluid;
   Spearmans' r = -0.976 with a probability
   <0.0001  (Steel and Torrie, 1980).

   Literature Cited
   Petrazzuolo, G. 1983. Proposed Method-
     ology: Drilling Fluids Toxicity Test for the
     Offshore Subcategory; Oil and Gas Ex-
     traction Industry. Technical Resources,
     Inc., Bethesda, MD 20817.  Draft dated
     May 19,  1983.
   Steel,  R.G. and J.H.  Torrie.  1980.
     Principles and Procedures of Statistics,
     2nd ed.  McGraw-Hill, New York, NY.
     633 pp.
   U.S.  Environmental  Protection Agency.
     1983.  Issuance  of Final General
     NPDES Permits for Oil and  Gas Opera-
     tions on the Outer Continental Shelf
     (OCS) of  Alaska;  Norton  Sound  and
     Beaufort Sea. Federal Register Vol. 48,
     No. 236,  December  7,  1983, pp.
     54881-54897.
        Table3.    Results of Acute Toxicity Tests with Mysids fMysidopsis babiajand Two Generic Drilling
                  Fluids Conducted at U.S. EPA, Gulf Breeze, Florida, and Narragansett, Rhode Island,
                  During August-September 1983
       Test Location
            Drilling Fluid
96-hour SPPa LC50   95% Confidence Limits
Gulf Breeze

Narragansett

#1
#5
XI
#5
2.7%
No Median Effect*
2.8%
No Median Effect
2.5-2.9%
___
2.5-3 0%
--
       'The suspended paniculate phase (SPP) was prepared by mixing 1 part drilling fluid with 9 parts
        seawater. Therefore, these values should be multiplied by 0.1 in order to related the 1:9 dilution
        tested to the SPP of the whole drilling fluid.
       "No median effect (50% mortality) occurred in  100% SPP.
        Table 4.
Comparative Acute Toxicity of Two Generic Drilling Fluids without and with Mineral Oil
Tested with Mysids (Mysidopsis bahia^ at U.S.  EPA,  Gulf Breeze, Florida. During
August-October. 1983
               Drilling Fluid*
                         96-hour SPP" LC50
                    95% Confidence Limits
#2
#2-07
#2-05
#2-70
tt8
#5-07
na-os
#8-10
51.6%
13.4%
1.08%
0.49%
29.3%
7.1%
0.90
0.76%
47.2-56.5%
11.1-16.9%
1.4-2.2%
0.39-0.62%
27.2-31.5%
5. 7-9.0%
0.74-1.1%
0.63-0.87%
                                             * The two digits following the generic drilling fluid number indicate the percentage of mineral oil in
                                              the fluid.
                                             "The suspended paniculate phase (SPP) was prepared by mixing 1 part drilling fluid with 9 parts
                                              seawater.  Therefore, these values should be multiplied by 0.1 in order to re/ate the 1.9 dilution
                                              tested to the SPP of the whole drilling fluid.
                                                The EPA authors, T. W. Duke (also the EPA Project Officer, see below), P. R.
                                                  Parrish. R. M. Montgomery, S. D. Macauley. J. M. Macauley, and G. M.
                                                  Cripe are with Environmental Research Laboratory, Gulf Breeze, FL 32561.
                                                The complete report,  entitled "Acute Toxicity of Eight  Laboratory-Prepared
                                                  Generic Drilling Fluids to Mysids fMysidopsis bahia,/," (Order No. PB 84-199
                                                  850; Cost: $8.50,  subject to change) will be available only from:
                                                       National Technical Information Service
                                                       5285 Port Royal Road
                                                       Springfield. VA22161
                                                       Telephone: 703-487-4650
                                                The EPA Project Officer can be contacted at:
                                                       Environmental Research Laboratory
                                                       U.S. Environmental Protection Agency
                                                       Gulf Breeze. FL 32561
                                                                                   •ft- U S GOVERNMENT PRINTING OFFICE. 1984 — 759-01 5/7744
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
Official Business
Penalty for Private Use $?'.
                                                         AlitiViCt

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                   United States
                   Environmental Protection
                   Agency
Environmental Research
Laboratory
Duluth MN 55804
                   Research and Development
EPA-600/S3-84-069 Aug. 1984
&EPA         Project Summary
                   Partitioning of Cadmium,  Copper,
                   Lead  and Zinc Among
                   Paniculate  Fractions  and  Water
                   in Saginaw Bay (Lake Huron)

                   Kenneth R. Rygwelski, Jill M. Townsend, and V. Elliott Smith
                     An intensive study of toxic metals in
                   Saginaw Bay (Lake  Huron) during
                   1976-1979 has resulted in a large data
                   base on the  temporal and spatial
                   variability of Cd, Cu, Pb and Zn
                   concentrations in both the water and
                   suspended solids. Generally, a trend of
                   decreasing concentrations of both the
                   total and  dissolved metals from the
                   inner to the outer bay was observed.
                   Partition coefficients of all the metals
                   studied were not constant with respect
                   to time or space. Particles in the 10-74
                   /um  range  were found to contain the
                   majority of the particulate metal mass
                   in the water, and they sorbed metals to a
                   higher degree than  the other size
                   fractions considered.
                     This Project Summary was developed
                   by EPA's Environmental Research
                   Laboratory, Duluth, MN, to announce
                   key findings of the research project that
                   is fully documented in a separate report
                   of the same title (see Project Report
                   ordering information at back).

                   Table 1.   Sampling Program
Objectives
  The distribution of four trace metals,
cadmium, copper, lead, and zinc, was
studied in Saginaw Bay (Lake Huron) in
order to establish a large data base
suitable for future assessment of water
quality trends and the development of
mass balance models for metallic toxins.
A major objective was to determine the
importance of various  size fractions of
suspended solids in concentrating trace
metals in the water column.

Methodology
  During  1976-78, Cranbrook Institute
of Science carried out an intensive survey
of cadmium, copper, lead, and  zinc in
Sagmaw Bay. A total of 33 cruises were
conducted by sampling  up to 27 stations
on the bay  at approximately two-week
intervals during the months of April-
November. Table 1 lists the numbers and
types  of samples collected for the
laboratory analysts of these metals In
addition to these samples, other  param-
                                                       Year Sampled With Number Collected
Sample Types
Saginaw Bay Cruises
Whole Water
<.45 fjm (dissolved!
.45-10 ym (particulate)
10-74 /jm (particulate)
74-210 /jm (particulate)
210-1000 tint (particulate)
1976
374
336
1977
562
522
1978
313
313
92
92
138
138
                   Saginaw River Loadings
                    Whole Water

                   Precipitation
                    Whole Water
                      <.45 fjm (dissolved)
  160
   11
   11
              208
93
56
                          228
122
 56

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eters  measured  included chloride, con-
ductivity, non-filterable chlorophyll a, pH,
Secchi disc depth, temperature,  total
alkalinity, total  non-filterable residue,
and transmittance
  A serial filtration system designed for
this study was used to fractionate whole
water into various particle size fractions
(listed  in  Table  1) to  be  analyzed for
metals A separate filtration system was
used to filter whole water through a 45 pm
filter to obtain the dissolved fraction
  No  special  pre-treatment was neces-
sary for water  samples  analyzed for
metals, but paniculate samples  were
prepared by using a nitric  acid digestion
method  Samples were then analyzed
using flame and flameless atomic absorp-
tion spectrophotometry
  Care was taken in choosing equipment
made of materials that  would minimize
contamination in all phases of the sample
collection,  filtration,  digestion, and
analysis  Routine blank  checks  were
made  on sample bottles, the filtering
process,  and on paniculate  filters and
screens
  Accuracy of the metal  analysis was
determined  through participation  in
interlaboratory comparison studies and
by analysis of standard reference samples
and use of the standard  addition method
Results  of between-run analyses  of
standards  and  samples were  used  to
determine precision
Results
  The full report contains an overview of
the data and describes the spatial and
temporal distribution of zinc, copper, lead
and cadmium in Saginaw Bay  Partition
coefficients of all the metals studied were
not constant with respect to time  or
space Two types of partition coefficients
were determined, a Kpg (general Kp) and a
KpS (specific Kp). For all  four metals, the
Kps calculated for each of the specific size
fractions  (10-74 /urn, 74-210  pm, and
210-1000 /um) were within the range of
the Kpg values calculated using total non-
filterable  residue  data  Particles  in the
10-74 fjm range were found to contain
the majority of the paniculate metal mass
in the water and exhibited the highest Kps
of these metals.
  Partition coefficients  (Kps and Kpg)  in
Saginaw Bay increased as the suspended
solids  concentration  decreased   This
trend held for cadmium,  copper, zinc, and
lead (Figures  1-4)  Segment 4  was
chosen  to represent the largely oligotro-
phic outer bay, and segment 1  was typical
of the eutrophic inner bay.
     08 .
     0.6
     0.4 .
     0.2 .
        10
Figure 1.
          7CT1           10°           701

                  Suspended So/ids Concentration (ppmj

General partition coefficients for cadmium, 1976.
                                                                             1C
      08 -
      0.6 -
      04 .
      0.2 -
                                                                 Segment 1 -
                                                                 Segment 4 -
                                10*
                                \i(f
                                  \
                                   \
         704
         70"
                       70"
                          T
                         70°
 1
70'
702
                                                                             n
 Figure 2.
                 Suspended So/ids Concentration (ppm)

 General partition coefficients for copper, 1978.

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 c
 o
 03
 £
     0.8 -
     0.6 -
     04  .
     02 -
                                                             10*
                                                                Segment 1 - •

                                                                Segment 4 - °
         10
       10°           10"

Suspended So/ids Concentration fppm)
                                                               102
JO3
Figure 3.    General partition coefficients for zinc, 1976-1978
     02  -
  The figures also show that the fraction
 of  metal  dissolved  increases within a
 given segment as the suspended solids
 concentration decreases  This trend is
 predicted  by theory  if constant partition
 coefficients can  be  assumed within a
 given segment
  Data  for cadmium, copper,  lead, and
 zinc  as total metal,  dissolved metal,
 particulate metal mass in the water, and
 the concentration of metal in the particles
 are  presented  in  figures  and tables
 contained in the full report
  Gradients of decreasing concentration
 from  the  inner  to outer bay  segments
 were noted for total and dissolved metals
 studied and for other non-metal param-
 eters,  including  total  non-filterable
 residue, conductivity, chloride,  alkalinity,
 and non-filterable chlorophyll a. Quarter-
 ly and annual summaries of all non-metal
 parameters are  presented by bay seg-
 ments

 Recommendations
  These results indicate  an inverse
 relationship between the solids concen-
 tration and partition coefficients of these
 metals  in Saginaw Bay  Such a "mass
 effect" has  been  noted  elsewhere.
 However,  it is possible that the chemical
 nature of particulates and of  adsorbing
 metal species also plays an important role
 in partitioning  If all of these variables
 were well defined in Saginaw Bay, in both
 space and time, then it would be possible
 to predict partition coefficients in other
 fresh  water systems. Complete charac-
 terization of these  variables was not
 possible in this study, until such data are
 available, an empirical approach such as
 the one used here is probably  most
 appropriate to define partitioning.
  Quality  control  measures are  an
 important consideration in any study,
 particularly one  involving  analysis of
 trace metals Determining blank levelsfor
 equipment and  processes  used in the
 study was crucial to providing accurate
 results  Results  of such  quality control
 programs should be used in establishing
 analytical strategies and determining the
 reliability of the data generated.
  It was difficult to compare these data to
those of previous studies, as little parti-
tioning data on metals exists. It is hoped
that these results will provide  a  needed
base  of information  on trace metal
partitioning in waters of the Great Lakes.
                             Suspended Solids Concentration (ppm)
Figure 4.    General partition coefficients for lead, 1977-1978.

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     K. R. Rygwelski, J. M. Townsend, and V. E. Smith are with Cranbrook Institute of
     Science, Grosse lie. Ml 48138.
     V. J. Bierman is the EPA Project Officer (see below).
     The complete report,  entitled "Partitioning of Cadmium, Copper, Lead and Zinc
      Among Paniculate Fractions and Water in Saginaw Bay (Lake Huronj," (Order
      No. PB 84-209 899; Cost: $16.00. subject to change) will be available only from:
            National Technical Information Service
            5285 Port Royal Road
            Springfield, VA 22161
             Telephone: 703-487-4650
     The EPA Project Officer can be contacted at:
            Environmental Research Laboratory
            U.S. Environmental Protection Agency
            Narragansett. Rl 02882
     U.S GOVERNMENT PRINTING OFFICE, 1984 — 759-015/7761
United States
Environmental Protection
Agency
     Center for Environmental Research
     Information
     Cincinnati OH 45268
Official Business
Penalty for Private Use $300
             ~ '•- -> i :.
            ' '>'   "--   i
            - "/I.'..,,
"«;-r IJl>-  •"--!: !-Cr
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