Docstoc

Lab3 MW

Document Sample
Lab3 MW Powered By Docstoc
					Name ____________________       Practical Problems in Groundwater Hydrology            Chapter 7 - Problem 3



   GEOCHEMICAL EVALUATION OF INDUCED INFILTRATION FROM
         MIXING SURFACE WATER AND GROUNDWATER
            SOUTH WELL FIELD, COLUMBUS, OHIO




Well locations at the Columbus South Well Field (FR-202 limestone well located further to the
Introduction
          0

   The city of Columbus, Ohio and its surrounding metropolitan areas depend, in part, on
groundwater resources from a shallow glacial outwash aquifer to meet water demands. The city
accesses this resource through four collector wells constructed in the early 1980s that induce
infiltration from the nearby Scioto River and Big Walnut Creek. Early estimates indicated that as
much as 70 to 80% of the production from the four wells would be through induced infiltration of
surface water (see problem setup).

   This exercise uses geochemical data to examine the hydraulic connection between surface water
and the underlying sand and gravel aquifer. Quantifying this interaction is important for several
reasons. First, the production from the well field depends on how the aquifer system receives
recharge. If recharge through induced infiltration is less than predicted, a greater hydraulic stress is
placed on the aquifer creating a larger cone of depression and a larger capture zone than anticipated.
Second, the well field is located downstream of a major metropolitan area, which impacts the surface
water quality of local rivers.




                                               Page 1 of 30                                     Introduction
Name ____________________       Practical Problems in Groundwater Hydrology           Chapter 7 - Problem 3



    For example, several unlined and unregulated landfills and wastewater treatment plants exist
upstream of the Columbus South Well Field along with significant stormwater runoff. Recent
studies show that at low streamflow and drought conditions, up to 80% of the Scioto River
streamflow that flows past the well field during drought periods is from treated waste effluent from
the Jackson Pike wastewater treatment plant further upstream (see Figure 7.3.3B in the problem
setup).

   Determining the relative contribution of each water source (Scioto River, limestone aquifer, and
glacial aquifer) entering the collector wells is important to understanding the interaction and mixing
of groundwater and surface water. We assume a two-stage mixing model in our analysis. The first
stage is river water mixing with water in the glacial aquifer via induced infiltration created by the
four collector wells. Thus, we would expect that water in the glacial aquifer obtained from
observation wells that are closer to the pumping wells would be more influenced by the river water
chemistry (i.e., more influenced by induced infiltration). Conversely, water in the glacial aquifer
obtained from observation wells further from the four pumping wells should be less chemically
influenced by river water. This first stage mixing is examined by graphing the sodium versus
chloride concentrations on a scatter plot. The second stage of mixing is between the water in the
limestone aquifer and the mixed glacial-surface water from stage 1 (see Problem Setup for more
explanation).

   The "Limestone" worksheet contains concentration measurements and other chemical parameters
from 12 water analyses from four wells completed into the limestone aquifer. The "Glacial"
worksheet contains concentration measurements and other chemical parameters from 11 water
analyses from five wells completed into the shallow glacial aquifer. The "Collector_Wells"
worksheet contains measured concentrations and other chemical parameters from 12 water samples
in wells CW-101, CW-103, and CW-104. Finally, the "Scioto" worksheet contains concentrations
and other chemical parameters 12 water analyses from three Scioto River locations near CW-101,
CW-103, and CW-104. All of these samples appear in chronological order. Once the calculations
outlined in the instructions are complete, the concentrations will be plotted on a Piper diagram
("Piper" worksheet) and sodium versus chloride mixing diagrams ("Stage 1," "Stage 2 (101)," "Stage
2 (104)" worksheets). Complete the following instructions and answer the conceptual questions
concerning this surface water – groundwater mixing problem.




                                               Page 2 of 30                                    Introduction
Name ____________________       Practical Problems in Groundwater Hydrology             Chapter 7 - Problem 3



Instructions

   Use the provided concentration data from different sample localities to determine the mixing
patterns in the groundwater flow system.

1. Convert the concentration values of major cations and anions listed in the worksheets labeled
"Limestone," "Glacial," "Collector_Wells," and "Scioto" from mg/L to meq/L. This conversion
factor is explained in equation 7-10 of the Reference Book and should be entered in the cell beneath
the milligram per liter concentration values.

2. Calculate the TDS value for each water sample by summing the mg/L concentrations. (Note that
bicarbonate ions are converted to carbonate in the solid phase using the laboratory TDS method, thus
you must multiply the bicarbonate concentrations by 0.4917 before summation in the calculated TDS
method, as explained in Hem (1985).)

3. Calculate the cation and anion summations, cation/anion ratio, and the percentage difference in
cations and anions in each water sample, as described in the Reference Book and equation 7-4.



4. For each water sample, calculate the relative percentage of each cation and anion in the cells
assigned on the worksheets and determine the prevalent chemical character (PCC) for each sample
(see Reference Book). Label the PCC in the assigned cell.

5. Using the space provided on the "Summary" worksheet under "Average Composition by
Location," calculate the average percentages of major cation and anion concentrations of the water
samples from each source. The summation of relative cation and anion percentages for each sample
appears in the table as a check to account for 100% of the ions. Calculate the average TDS for each
water source in the space provided. The average percentage value for each ion are automatically
plotted on a Piper diagram (see "Piper" worksheet). Each locality has a different color and symbol.

6. Stage 1 mixing is between the glacial aquifer water and the Scioto River water, as described
above. To determine the amount of mixing between these two waters within the collector wells, you
need to graph the sodium concentrations versus chloride concentrations in meq/L on a XY scatter
plot. This plot allows you to calculate the amount of induced infiltration from the Scioto River to the
collector wells (see Reference Book for more explanation).

    Plot the sodium concentrations versus the chloride concentrations for the water samples from the
collector wells, Scioto River, and glacial wells (FR-73, FR-120, FR-147, and TH-73) for the 1987
sampling round only. This plot provides a "snapshot" in time of the water chemistry and allows you
to estimate the amount of induced infiltration. Be sure to include a legend of the source locations on
your plot. Print out this graph, which will be used for analysis of induced infiltration, as discussed in
the "Questions" worksheet.




                                                Page 3 of 30                                     Introduction
Name ____________________      Practical Problems in Groundwater Hydrology          Chapter 7 - Problem 3



7. Stage 2 mixing is between the water in the limestone aquifer and the mixed glacial-river water
from Stage 1. Wells FR-147 and TH-73 are assumed to be mixed glacial-river wells because of their
close proximity to collector wells CW-101 and CW-104, respectively. The geochemical data
support this assumption because of elevated TDS and ion concentrations in water from these well
based on the Stage 1 analysis. To determine the amount of mixing between these two waters within
the collector wells, plot the sodium concentration versus chloride concentration in meq/L on a XY
scatter plot.

   On the first graph, use concentrations from observation wells FR-147 (mixed glacial-river well)
and FR-148 (limestone well) and collector well CW-101 for the 1987 sampling round. For the
second plot, use well TH-73 (mixed glacial-river well), FR-149 (limestone well), and collector well
CW-104 from the 1987 sampling round.




                                              Page 4 of 30                                   Introduction
              Name ____________________   Practical Problems in Groundwater Hydrology   Chapter 7 - Problem 3




nticipated.
the surface




                                                         Page 5 of 30                            Introduction
             Name ____________________   Practical Problems in Groundwater Hydrology   Chapter 7 - Problem 3




nd mixing




arameters




     Stage




                                                        Page 6 of 30                            Introduction
               Name ____________________   Practical Problems in Groundwater Hydrology   Chapter 7 - Problem 3




ll beneath



ethod, thus
ulated TDS




ch sample




wells, you

River to the


s from the

allows you
 cations on
 iscussed in




                                                          Page 7 of 30                            Introduction
               Name ____________________   Practical Problems in Groundwater Hydrology   Chapter 7 - Problem 3




use of their


ers within




                                                          Page 8 of 30                            Introduction
Name ____________________       Practical Problems in Groundwater Hydrology            Chapter 7 - Problem 3



   GEOCHEMICAL EVALUATION OF INDUCED INFILTRATION FROM
         MIXING SURFACE WATER AND GROUNDWATER
            SOUTH WELL FIELD, COLUMBUS, OHIO

Questions0(7 Total; 2 Optional)

Question #1. What is the predominant chemical character (PCC) of the end-member waters based
on the available water samples?

Limestone: Ca-HCO3

Glacial: Ca-HCO3

Collector Wells: Ca-HCO3

Scioto River: Ca-SO4



  Question #2. Which samples do NOT have a proper cation-anion balance based on the
  description in Problem 1 of this chapter in the Reference Book (list the aquifer, sample
  location, and sample date)? What are some of the possible reasons for the charge
  imbalances in these water samples?



  If the percent difference is negative, then the sample has either insufficient cations or
  excess of anions and vice versa. So far example, in the Limestone wells, the well FR-202
  on September 8th has a negative percent difference, so the sample must have either
  insufficent cations of more anions. In the Glacial sample, the well FR-147 from December
  8th, there is a postive percent difference so there must be an excess of cations or insuffient
  amount of anions in the water analysis

  These imbalances can be caused from missing analysis, lab errors, particle pollution,
  minerals are precipitated or the ionic species themselves are not balanced.




                                               Page 9 of 30                                        Questions
Name ____________________       Practical Problems in Groundwater Hydrology           Chapter 7 - Problem 3




Question #3. FR-73 is a glacial well completed far away from the collector wells and for the
purposes of the problem is considered to represent the background water chemistry of the glacial
aquifer (not chemically impacted by pumping). The water from this well is considered to be one of
the end members in Stage 1 mixing, with water from the Scioto River being the other end member.
Thus, the water chemistry in the collector wells and the impacted glacial wells are a mixture of these
two end members. Using the methodology described in the Reference Book under induced
infiltration in Problem 3, estimate the relative impact of pumping on each of the following glacial
wells TH-73, FR-120, and FR-147 as well as the collector wells. Use the sodium concentration
versus chloride concentration plots you created to estimate the relative percentage of glacial water
(represented by FR-73) and Scioto River water in each of the impacted glacial wells (TH-73, FR-
120, FR-147) and for the collector wells. Record the percentages in the following table.




                              Percentage Water From Source
TH-73                       Scioto River  Glacial Aquifer (FR-73)
FR-120
FR-147
Collector Wells



Question #4. Use the sodium concentration versus chloride concentration plots you created for
Stage 2 mixing to determine the relative percentage of glacial-river water and limestone water in
each of the two collector wells. Record the percentages in the following table.

                              Percentage Water From Source
CW-101                       Limestone         Glacial-River
CW-104




                                               Page 10 of 30                                     Questions
Name ____________________       Practical Problems in Groundwater Hydrology            Chapter 7 - Problem 3



Question #5. If a chemically conservative pesticide (i.e., one that does not sorb onto the sediments)
was present in the Scioto River, what would its concentration have to be in order to cause the
collector well water to contain 5 mg/L, thus not meeting the drinking water standard? Consider
advection only. (Show your work.)




Optional Questions

Question #6. The Piper diagram on the "Piper" worksheet allows for graphical comparison of the
major cation and anion concentrations for all of the water samples at the same time. Based on this
diagram, do data from the different water sources cluster together in the cation and anion portions of
this diagram?



The cluster towrds the cation partion on the diagrams

Is the collector well data directly in between the Scioto River data and glacial aquifer data in the
mixing diamond portion of the graph thus indicating a mixing of only these two waters (see
Reference Book)? Is the impact of the limestone aquifer water on the collector well data evident in
the mixing diamond?

I would say that yes, the collector well data directly in between the Scioto and Glacials aquifers
represent mixing of the samples.

Yes, you can clearly see that the limestone aquifer is present and is mixing with the glacial, Scioto,
and collector well data.




                                               Page 11 of 30                                      Questions
Name ____________________       Practical Problems in Groundwater Hydrology           Chapter 7 - Problem 3



Question #7. Our assumption in Stage 1 mixing addressed in Problem 3 was that well FR-73 was
not chemically influenced by the pumping of the collector wells and thus could be considered
representative of the glacial end member water. Based on the water chemistry data, does this
assumption appear to be reasonable? How is the water chemistry different in glacial wells, such as
FR-73, which are far from the pumping collector wells versus the water within the collector wells?


the glacial wells are different from any other wells because it comes from a different water source
and is further away from the collector wells, therefore having been less affecting by the chemistry of
those wells further away.




                                               Page 12 of 30                                     Questions
Name ____________________   Practical Problems in Groundwater Hydrology   Chapter 7 - Problem 3




                                           Page 13 of 30                             Questions
               Name ____________________   Practical Problems in Groundwater Hydrology   Chapter 7 - Problem 3




 be one of
 member.
ure of these




                                                          Page 14 of 30                             Questions
              Name ____________________   Practical Problems in Groundwater Hydrology   Chapter 7 - Problem 3



sediments)




son of the

portions of




al, Scioto,




                                                         Page 15 of 30                             Questions
              Name ____________________   Practical Problems in Groundwater Hydrology   Chapter 7 - Problem 3




hemistry of




                                                         Page 16 of 30                             Questions
Name ____________________                             Practical Problems in Groundwater Hydrology                  Chapter 7 - Problem 3



                        Limestone Aquifer Wells
                                                                                                                   98 = mg/L concentration
     Sample Location                      FR-202       FR-202      FR-202     FR-202      FR-149      FR-149      FR-149      FR-149
       Sample Date                        8/22/1988     9/8/1987   4/9/1982   8/20/1979   9/10/1992   9/10/1991   8/22/1988   9/4/1987
      Water Temp (˚C)                        13          13.8       11.5         14         13.5       12.9         15.5        13
           SpC                             1020          986        901        1100        1330        545            --       952
            pH                              7.4           7.3        6.8        7.2           7         6.8          7.2        7.5
            Ca2+                            120          120        101         110         100         44          110         70
          0.0499                           5.99          5.99       5.04       5.49         4.99       2.20         5.49       3.49
Ions meq/L conversion




            Mg+                              47           44         43          44          67         26           72         51
          0.0822                            3.9           3.6        3.5        3.6          5.5        2.1          5.9        4.2
Ion         Na+                              27           27         28          28          53         22           55         46
   s      0.0435                            1.2           1.2        1.2        1.2          2.3        1.0          2.4        2.0
me           K+                             2.2           2.2        2.4        2.3          9.1        4.6          8.8        7.8
q/L       0.0256                            0.1           0.1        0.1        0.1          0.2        0.1          0.2        0.2
  co
          HCO3-                             427          416        400         430         769        309          720        476
  nv
ers       0.0164                           7.00          6.82       6.56       7.05        12.60       5.06        11.80       7.80
ion        SO42-                            190          190        220         200          65         84           32         38
fac       0.0208                           3.96          3.96       4.58       4.16         1.35       1.75         0.67       0.79
 tor        Cl-                              13           9.8        2.3        2.7         100         41          130         79
          0.0282                           0.37          0.28       0.06       0.08         2.82       1.16         3.67       2.23
       S TDS (mg/L)                         609          598        593         598         772        374          762        526
                         S Cation meq/L     11.1         10.8        9.9        10.4        13.0        5.4         14.0        9.9
                         S Anion meq/L      11.3         11.1       11.2        11.3        16.8        8.0         16.1       10.8
                          % Difference      -1.1         -1.0       -6.4        -4.2       -12.5       -19.1        -7.0       -4.5
                          Cation/Anion      1.0          1.0        0.9         0.9         0.8         0.7         0.9        0.9
                              % Ca           54           55         51          53          38         41           39         35
                              % Mg           35           33         36          35          42         40           42         42
                            % Na + K         11           11         13          12          19         20           19         22
                            % HCO3           62           62         59          62          75         64           73         72
                             % SO4           35           36         41          37           8         22            4          7
                              % Cl            3            3          1           1          17         15           23         21
                                 PCC      Ca-HCO3 Ca-HCO3 Ca-HCO3 Ca-HCO3 Mg-HCO3 Ca-HCO3 Mg-HCO3 Mg-HCO3

                        check:             100.00       100.00     100.00     100.00      100.00      100.00      100.00      100.00




                                                                     Page 17 of 30                                             Limestone
            Name ____________________           Practical Problems in Groundwater Hydrology   Chapter 7 - Problem 3




                Unit Legend
mg/L concentration 4.89 = meq/L concentration
             FR-148      FR-148      FR-148     FR-270
             3/25/1991   8/31/1990   4/2/1990   8/18/1988
               14.5         14         12         13
              1300        1620       1140        757
                7.5         7.2         7         7.4
               130         190        180         93
               6.49        9.48       8.98       4.64
                85          87         85         39
                7.0         7.2        7.0        3.2
                46          47         43         8.5
                2.0         2.0        1.9        0.4
                5.3         5.6        6.5        1.4
                0.1         0.1        0.2        0.0
               245         384        390        439
               4.02        6.29       6.39       7.20
               560         620        560         52
              11.66       12.91      11.66       1.08
                77          69         67         10
               2.17        1.95       1.89       0.28
              1024        1207       1133        420
               15.6        18.8       18.0         8.3
               17.8        21.1       19.9         8.6
               -6.7        -5.8       -5.1        -1.8
               0.9         0.9        0.9         1.0
                42          50         50          56
                45          38         39          39
                14          12         11           5
                23          30         32          84
                65          61         58          13
                12           9          9           3
             Mg-SO4      Ca-SO4      Ca-SO4     Ca-SO4

             100.00      100.00      100.00     100.00




                                                               Page 18 of 30                             Limestone
Name ____________________                             Practical Problems in Groundwater Hydrology                 Chapter 7 - Problem 3



                                                                                                                             Unit Legend
                        Glacial Aquifer Wells                                                           98 = mg/L concentration 4.89 = meq/L co
                                                                                                                             FR-104
     Sample Location                      FR-147       FR-147      FR-147     FR-147      FR-147      FR-147     FR-120      TH-73
       Sample Date                        8/21/1995    6/29/1995   5/1/1995   12/8/1994   8/30/1994   9/4/1987   9/11/1987   9/9/1987
      Water Temp (˚C)                      14.3          14.2         --       13.5         14         12.9       12.5        11.9
           SpC                             941           953        877        925         962         896        672         742
            pH                              7.2            7         6.9        7.1          7          7.5        7.4         7.7
            Ca2+                           120           120        120        130         120         120         99         100
          0.0499                           5.99          5.99       5.99       6.49        5.99        5.99       4.94        4.99
Ions meq/L conversion




Ion         Mg+                             34            34         33         36          37          40         32          37
   s      0.0822                            2.8           2.8        2.7        3.0         3.0         3.3        2.6         3.0
me          Na+                             26            26         26         27          24          14         4.9         6.2
q/L       0.0435                            1.1           1.1        1.1        1.2         1.0         0.6        0.2         0.3
  co         K+                             2.7           2.8        2.9         3          2.9         1.8        1.7         1.5
  nv      0.0256                            0.1           0.1        0.1        0.1         0.1         0.0        0.0         0.0
ers       HCO3-                            364           397        361        304         348         378        366         358
ion       0.0164                           5.97          6.51       5.92       4.98        5.70        6.20       6.00        5.87
fac        SO42-                           150           150        150        150         170         120         53          90
 tor
          0.0208                           3.12          3.12       3.12       3.12        3.54        2.50       1.10        1.87
            Cl-                             52            51         54         51          45          29         15          14
          0.0282                           1.47          1.44       1.52       1.44        1.27        0.82       0.42        0.39
       S TDS (mg/L)                        564           579        563        546         570         511        386         425
                         S Cation meq/L     10.0         10.0        9.9        10.7        10.1        9.9        7.8         8.3
                         S Anion meq/L      10.6         11.1       10.6         9.5        10.5        9.5        7.5         8.1
                          % Difference      -2.8         -5.1       -3.2         5.7        -1.8        2.2        2.0         1.2
                          Cation/Anion      0.9          0.9        0.9         1.1         1.0         1.0        1.0         1.0
                              % Ca           60           60         60          61          59         60         63          60
                              % Mg           28           28         27          28          30         33         34          36
                            % Na + K         12           12         12          12          11          7          3           4
                            % HCO3           57           59         56          52          54         65         80          72
                             % SO4           30           28         30          33          34         26         15          23
                              % Cl           14           13         14          15          12          9          6           5
                                 PCC      Ca-HCO3 Ca-HCO3 Ca-HCO3 Ca-HCO3 Ca-HCO3 Ca-HCO3 Ca-HCO3 Ca-HCO3

                        check:              100          100        100         100         100        100         100        100




                                                                     Page 19 of 30                                               Glacial
           Name ____________________           Practical Problems in Groundwater Hydrology   Chapter 7 - Problem 3



       Unit Legend
entration 4.89 = meq/L concentration


             FR-73      FR-73       FR-18
             9/4/1987   5/29/1980   9/8/1987
              14.5       12.5        12.5
              699        658         1010
               7.3        7.4         7.1
              100         95          120
              4.99       4.74        5.99
               34         33           38
               2.8        2.7         3.1
               3.3        14           34
               0.1        0.6         1.5
               1.4        2.7         2.2
               0.0        0.1         0.1
              376        410          445
              6.16       6.72        7.29
               63         56           88
              1.31       1.17        1.83
               5.1        4.2          87
              0.14       0.12        2.45
              392        406          588
               8.0        8.1        10.6
               7.6        8.0        11.6
               2.2        0.8        -4.2
               1.0        1.0        0.9
               63         58          56
               35         33          29
                2          8          14
               81         84          63
               17         15          16
                2          1          21
            Ca-HCO3 Ca-HCO3 Ca-HCO3

              100         100        100




                                                              Page 20 of 30                                Glacial
Name ____________________                             Practical Problems in Groundwater Hydrology               Chapter 7 - Problem 3



                        Collector Wells
                                                                                                                98 = mg/L concentration
     Sample Location                      CW-101       CW-103      CW-104     CW-101     CW-103     CW-104     CW-101      CW-103
       Sample Date                         9/3/1987     9/3/1987   9/3/1987   9/5/1989   9/5/1989   9/5/1989   9/13/1991   9/13/1991
      Water Temp (˚C)                       15.5          14        13.5         --         --         --         --          --
           SpC                              774          793        788          --         --         --         --          --
            pH                               7.3          7.2        7.4        7.3        7.3        7.4       7.25        7.16
            Ca2+                            100          110        110        115        120        109        122         132
          0.0499                            4.99         5.49       5.49       5.74       5.99       5.44       6.09        6.59
Ions meq/L conversion




Ion         Mg+                              31           33         33         30         32         30         33          37
   s      0.0822                             2.5          2.7        2.7        2.5        2.6        2.5        2.7         3.0
me          Na+                              22           18         19         20         17         24         24          18
q/L       0.0435                             1.0          0.8        0.8        0.9        0.7        1.0        1.0         0.8
  co         K+                               3           2.7        2.1         3         2.7        2.8        3.6         3.2
  nv      0.0256                             0.1          0.1        0.1        0.1        0.1        0.1        0.1         0.1
ers       HCO3-                             305          323        323        315        307        322        310         314
ion       0.0164                            5.00         5.29       5.29       5.16       5.03       5.28       5.08        5.15
fac        SO42-                            110          120        100        155        160        140        145         167
 tor
          0.0208                            2.29         2.50       2.08       3.23       3.33       2.91       3.02        3.48
            Cl-                              36           32         35         39         37         50         43          38
          0.0282                            1.02         0.90       0.99       1.10       1.04       1.41       1.21        1.07
       S TDS (mg/L)                         452          475        458        517        520        514        523         550
                         S Cation meq/L      8.6          9.1        9.1        9.2        9.4        9.0        9.9         10.5
                         S Anion meq/L       8.3          8.7        8.4        9.5        9.4        9.6        9.3          9.7
                          % Difference       1.6          2.0        4.1       -1.8        0.1       -3.1        3.2          4.0
                          Cation/Anion       1.0          1.0        1.1       1.0         1.0       0.9         1.1         1.1
                              % Ca           58           61         60         63         64         60         61           63
                              % Mg           30           30         30         27         28         27         27           29
                            % Na + K         12            9         10         10          9         12         11            8
                            % HCO3           60           61         63         54         53         55         55           53
                             % SO4           28           29         25         34         35         30         32           36
                              % Cl           12           10         12         12         11         15         13           11
                              PCC         Ca-HCO3 Ca-HCO3 Ca-HCO3 Ca-HCO3 Ca-HCO3 Ca-HCO3 Ca-HCO3 Ca-HCO3

                        check:              100          100        100        100        100        100         100         100
                        Double-chk:         100          100        100        100        100        100         100         100




                                                                     Page 21 of 30                                     Collector_Wells
            Name ____________________            Practical Problems in Groundwater Hydrology   Chapter 7 - Problem 3




                Unit Legend
mg/L concentration 4.89 = meq/L concentration
             CW-104      CW-101      CW-103      CW-104
             9/13/1991   9/18/1993   9/18/1993   9/18/1993
                --          --          --          --
                --          --          --          --
              7.27        7.26        7.22        7.26
              125         134         143         131
              6.24        6.69        7.14        6.54
               35          31          35          33
               2.9         2.5         2.9         2.7
               28          22          18          27
               1.2         1.0         0.8         1.2
               3.9         3.8         3.4         4.3
               0.1         0.1         0.1         0.1
              317         302         309         312
              5.20        4.95        5.06        5.11
              145         151         187         161
              3.02        3.14        3.89        3.35
               57          37          32          44
              1.61        1.04        0.90        1.24
              550         527         570         554
               10.4        10.3        10.9        10.5
                9.8         9.1         9.9         9.7
                3.0         5.9         4.9         4.1
               1.1         1.1         1.1         1.1
                60          65          66          62
                28          25          26          26
                13          10           8          12
                53          54          51          53
                31          34          39          35
                16          11           9          13
            Ca-HCO3 Ca-HCO3 Ca-HCO3 Ca-HCO3

               100         100         100         100
               100         100         100         100




                                                                Page 22 of 30                        Collector_Wells
Name ____________________                            Practical Problems in Groundwater Hydrology                   Chapter 7 - Problem 3



                        Scioto River Water near the following collector wells
                                                                                                                    98 = mg/L concentration
     Sample Location                      CW-101      CW-101     CW-101      CW-101      CW-101      CW-101      CW-101       CW-103
       Sample Date                        1/9/1995    9/1/1994   8/15/1994   8/26/1988   8/18/1987   8/25/1981   11/20/1979   8/26/1988
      Water Temp (˚C)                       6.5        22.5       22.5         23         25.5         25          12.5         21
           SpC                             1230        638        634         780         810         899          895         792
            pH                              8.4         7.6        7.6         7.8         6.9         7.1          7.5         7.8
            Ca2+                             79         65         62          84          81          89           82          83
          0.0499                           3.94        3.24       3.09        4.19        4.04        4.44         4.09        4.14
Ions meq/L conversion




Ion         Mg+                              22         19         19          26          25          27           25          26
   s      0.0822                            1.8         1.6        1.6         2.1         2.1         2.2          2.1         2.1
me          Na+                             110         29         28          49          48          55           33          49
q/L       0.0435                            4.8         1.3        1.2         2.1         2.1         2.4          1.4         2.1
  co         K+                             6.5         5.2        5.2         6.3         7.8         7.8          4.5         6.3
  nv      0.0256                            0.2         0.1        0.1         0.2         0.2         0.2          0.1         0.2
ers       HCO3-                             198        143        152         140         180         183          260         165
ion       0.0164                           3.25        2.34       2.49        2.29        2.95        3.00         4.26        2.70
fac        SO42-                            190        120        100         190         180         170          100         180
 tor
          0.0208                           3.96        2.50       2.08        3.96        3.75        3.54         2.08        3.75
            Cl-                             170         44         45          64          62          68           49          64
          0.0282                           4.79        1.24       1.27        1.80        1.75        1.92         1.38        1.80
       S TDS (mg/L)                         675        353        334         488         492         507          421         489
                         S Cation meq/L    10.7         6.2        6.0         8.6          8.4        9.3          7.7         8.6
                         S Anion meq/L     12.0         6.1        5.8         8.1          8.4        8.5          7.7         8.3
                          % Difference     -5.7         1.0        1.4         3.4         -0.4        4.5         -0.2         1.9
                          Cation/Anion     0.9          1.0        1.0         1.1         1.0         1.1         1.0          1.0
                              % Ca          37          52         52          49           48         48           53          48
                              % Mg          17          25         26          25           25         24           27          25
                            % Na + K        46          22         22          27           27         28           20          27
                            % HCO3          27          39         43          28           35         35           55          33
                             % SO4          33          41         36          49           44         42           27          45
                              % Cl          40          20         22          22           21         23           18          22
                                 PCC      Na,K-Cl     Ca-SO4 Ca-HCO3 Ca-SO4              Ca-SO4      Ca-SO4 Ca-HCO3 Ca-SO4

                        check:             100          100        100         100         100         100         100          100
                                           100          100        100         100         100         100         100          100




                                                                    Page 23 of 30                                                     Scioto
           Name ____________________            Practical Problems in Groundwater Hydrology   Chapter 7 - Problem 3




                Unit Legend
mg/L concentration 4.89 = meq/L concentration
            CW-103      CW-104      CW-104      CW-104
            8/18/1987   8/26/1988   8/18/1987   8/18/1987
             27.5         23         27.7         25
             800           --        790         860
              7.2         7.8          7          7.5
              81          83          82          87
             4.04        4.14        4.09        4.34
              24          26          24          25
              2.0         2.1         2.0         2.1
              48          49          47          46
              2.1         2.1         2.0         2.0
              8.2         6.3         7.5         8.2
              0.2         0.2         0.2         0.2
             180         156         176         178
             2.95        2.56        2.88        2.92
             170         190         190         190
             3.54        3.96        3.96        3.96
              61          64          62          64
             1.72        1.80        1.75        1.80
             481         495         499         508
              8.3         8.6          8.3         8.6
              8.2         8.3          8.6         8.7
              0.6         1.5         -1.7        -0.4
              1.0         1.0         1.0         1.0
              49          48           49          50
              24          25           24          24
              28          27           27          26
              36          31           34          34
              43          48           46          46
              21          22           20          21
            Ca-SO4      Ca-SO4      Ca-SO4      Ca-SO4

              100         100         100         100
              100         100         100         100




                                                               Page 24 of 30                                 Scioto
Name ____________________     Practical Problems in Groundwater Hydrology            Chapter 7 - Problem 3



                        GEOCHEMICAL EVALUATION OF INDUCED INFILTRATION FROM
                              MIXING SURFACE WATER AND GROUNDWATER
                                 SOUTH WELL FIELD, COLUMBUS, OHIO



                                              AVERAGE COMPOSITION BY LOCATION
                                                                      Total
           Location/Source Water     % Ca       % Mg     % Na + K    Cation   % HCO3     % SO4

         Limestone Aquifer             47        39          14       100       58         32
                         check:                                       100
         Glacial Aquifer               60        31          9        100       66         24
                                                                      100
         Collector Wells               62        28          10       100       56         32
                                                                      100
         Scioto River                  49        24          27       100       36         42
                                                                      100




                                             Page 25 of 30                                       Summary
      Name ____________________    Practical Problems in Groundwater Hydrology   Chapter 7 - Problem 3



INFILTRATION FROM
OUNDWATER
US, OHIO




                 Total     TDS
        % Cl     Anion    (mg/L)

         10       100       718

         10       100       503

         12       100       517

         23       100       478




                                                  Page 26 of 30                             Summary
Name ____________________        Practical Problems in Groundwater Hydrology                                Chapter 7 - Problem 3




                                 SO4 + Cl         Ca + Mg                      Location of Sources

                                                                                   Scioto River


                                                                                   Glacial Wells


                                                                                   Limestone Aquifer


                                                                                   Collector Wells


                            Mg                                           SO4




      Ca                               Na+K HCO3+CO3                                                   Cl




                                                Page 27 of 30                                                              Piper
Name ____________________         Practical Problems in Groundwater Hydrology                                 Chapter 7 - Problem 3



                                  Stage 1 Mixing - Glacial vs. River

               2.50




               2.00




               1.50
  Cl (meq/L)




               1.00

                                                                                      FR-73
                                                                                      TH-73
                                                                                      FR-147
               0.50
                                                                                      FR-120
                                                                                      Scioto River
                                                                                      Collector Wells

               0.00
                      0.0   0.5     1.0                    1.5                  2.0                     2.5
                                            Na (meq/L)




                                                 Page 28 of 30                                                              Stage 1
Name ____________________           Practical Problems in Groundwater Hydrology                         Chapter 7 - Problem 3



                                  Stage 2 Mixing - Glacial vs. Limestone

               2.50




               2.00




               1.50
  Cl (meq/L)




               1.00




                                                                          FR-147 (Glacial-River Well)
               0.50
                                                                          CW-101

                                                                          FR-148 (Limestone Well)

               0.00
                      0.0   0.5          1.0                       1.5                 2.0               2.5
                                                 Na (meq/L)




                                                   Page 29 of 30                                                Stage 2 (101)
Name ____________________           Practical Problems in Groundwater Hydrology                                 Chapter 7 - Problem 3



                                  Stage 2 Mixing - Glacial vs. Limestone

               2.50




               2.00




               1.50
  Cl (meq/L)




               1.00




                                                                      FR-149 (Limestone Well)
               0.50

                                                                      CW-104

                                                                      FR-104 TH-73 (Glacial-River Well)

               0.00
                      0.0   0.5        1.0                    1.5                   2.0                   2.5
                                               Na (meq/L)




                                                   Page 30 of 30                                                        Stage 2 (104)

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:23
posted:1/2/2012
language:
pages:30