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Women with Infant Children Radon Study 1992-1993

INTRODUCTION

During the third year of a three-year grant from the U.S. Environmental Protection Agency (EPA), the North Dakota State Department of Health and Consolidated Laboratories (NDSDHCL) began testing for radon in 10% of the 9,900 homes served by the Women, Infants, and Children Assistance Program (WIC). On October 28, 1992, at the WIC annual meeting, the Department distributed 2,468 radon testing kits to WIC coordinators. This was enough kits to sample 10% of the WIC homes.

SAMPLING

The Department followed EPA guidance for sampling protocol. Participants were asked to:

  1. Sample during the times suggested by their WIC person.
  2. Sample the lowest two levels of their home.
  3. Place the sample vials in the room that is occupied the most.
  4. Sample for 48 hours.
  5. Mail sample vials and information sheet as soon after closing as is possible.

QUALITY ASSURANCE

Two detectors were given to each recipient. They were instructed to place one detector on each level of the home in the room that is utilized the most. Duplicates were provided to 10% of the test recipients. They were instructed to place the duplicate directly beside a host test detector. The Department followed EPA guidance to formulate its Quality Assurance Plan and used the National Database format for recording collected data.

The precision was determined by utilizing a coefficient of variation computer program. Due to misunderstandings, many of the duplicates were placed in different rooms on the same level. Therefore, many precision checks are of a level rather than of a room. During this survey, field blanks were not utilized.

The accuracy was determined by the Department's Laboratory from a series of samples that were exposed in radon chambers. The chambers are located in laboratories owned by the Niton or Bowser Morner Companies. The accuracy of the results of the samples measured by the NDSDHCL were acceptable according to EPA guidelines.

The survey was conducted from November 1992 to April 1993. Data continued to arrive at the Department during the entire survey and through May. Only data collected from the normal radon testing season, which is considered to be November through April, was utilized. The collected data was verified and stratified by parameters.

The original database represented 1,198 samples. Forty-eight samples were lost, not analyzed, or were not mailed to the laboratory in time. Eighty-nine of the duplicate samples could not be used in the averaging. The final database contained 98 duplicate samples and 973 normal or regular (NR) samples for a total of 1,061 samples.

                    1061 
% sample recovery = ---- x 100 = 43.0%
                    2468

This survey was voluntary and samples were not received from the following counties: Billings, Eddy, Golden Valley, Grant, McKenzie, Mercer, Sioux, and Slope. See Table 14.

The county percentage of samples whose concentration is greater than 4 picocuries per liter is shown in Table 14. The city/county percentages are shown in Table 15.

Description of Statistics by Selected Parameters

Data for parameters as required for the national database may be found in Table 13.

Basement Sump

Many buildings are built on flood plains and a large number have sumps in basements. Sumps are especially prevalent in cities built near rivers. It has been noted in previous survey reports by the Department, that basements with sumps generally have higher radon concentrations. The radon concentration can usually be lowered by covering the sump. A surprising 234 samples, about 22%, were from homes containing sumps.

Mobile Homes

Of 1,061 WIC samples, 94 (8.9%) were mobile homes. The average radon concentration for mobile homes was 5.9 pCi/l. The average for all samples was 6.1 pCi/l. The Department found it surprising that the average mobile home radon concentration was almost as high as the concentration in conventional homes. The reasons for mobile homes having such high concentrations of radon are unknown at this time.

Heat Distribution

An "other" category was added to the Federal Database for heat distribution systems to include combination systems and wood burners that are only used during the winter heating season. Forced air was the most common type of heat distribution system (62.85%). The hot water system was the next most common form of heat distribution (15.6%).

Test Location Floor

The most common sampling floors were the first floor (54.7%) and the basement (38.4%).

Basement, Crawl Space, or Slab-on-Grade

The basement, crawl space, and slab-on-grade building styles can be found in combinations in some older homes. Older homes generally have crawl spaces for small houses and basements for larger houses. Some houses are a combination of all three types. Slab-on-grade is not a popular home building style in North Dakota, comprising only 1.6% of the samples.

Type of Building

Single family buildings comprise 82.6% of the samples. Following Federal guidelines, the Department categorized the buildings such that most buildings were contained in the first four types. The most popular other type of building selected was multifamily.

Room Type

The most used rooms were the living room, bedroom, family room, and unfinished basement.

VARIANCE

Of the total variance, 0.35% was due to the geological regions, 15.17% due to the county, 29.64% due to error, and 54.84% due to building.

There are 47 counties, 104 cities, 545 buildings, 3 geological regions, and Yes or No indicating whether or not the facility contains a basement sump. Major contributors to variance are the county, the city, the building, and the sump.

Figure 5 indicates the data is log normal except for lower concentrations.

FIGURE 5 - WIC RADON STUDY 1992-1993

WIC Graph

Number of Samples: 1061

SUMMARY AND CONCLUSIONS

Conducting a survey using the National Database is labor intensive. Often the instructions to testing applicants are either not understood or not followed. The Department conducted an organizational meeting in which the application was explained, questions answered, and test kits handed out, however, in many cases, the proper testing protocol was still not followed.

This survey shows WIC homes have less of a radon concentration than do the homes surveyed in the 1988 study. The problem is that both average concentrations in North Dakota are greater than 4 pCi/l; i.e., WIC homes (6.1) and homes (7.0).

TABLE 13

WIC SURVEY STATISTICS BY PARAMETER

                                                                                     
                                                                             PERCENTAGE OF              
                                NUMBER                     ARITHMETIC           SAMPLES          
                                  OF       ARITHMETIC       STANDARD          GREATER THAN                      
PARAMETERS                      SAMPLES       MEAN         DEVIATION       4 pCi/l    20 pCi/l                      
      
MOBILE HOME                                                                                         
  Yes                              94          5.9            19.7           14.9        4.3        
  No                              967          6.1             7.3           52.0        3.9        

TYPE OF BUILDING                                                                                    
  Single Family                   852          6.6             9.5           52.2        4.6        
  Multi Family                    173          4.0             7.3           29.5        1.2        
  School                            1          1.3             0.0            0.0        0.0        
  Other                             6          4.4             2.2           66.7        0.0        

BASEMENT CRAWL SPACE                                                                                
 SLAB-ON-GRADE                                                                                        
  Basement                        821          6.5             9.4           53.3        4.3        
  Crawl Space                     120          2.8             2.3           23.3        0.0        
  Slab-on-Grade                    16          3.9             5.2           31.3        6.3        
  Other                            65          8.2            13.5           41.5        7.7        

TEST LOCATION FLOOR                                                                                 
  Basement                        403          8.7            12.1           70.5        7.4        
  First Floor                     574          4.6             5.1           37.6        1.9        
  Second Floor & Above             73          4.6            12.0           23.3        1.4        

HEAT DISTRIBUTION TYPE                                                                              
  Hot Air                         636          6.1             9.4           49.8        3.3        
  Hot Water                       158          4.8             9.0           37.3        2.5        
  Radiant                          72          7.1             7.3           54.2        6.9        
  Individual Room Units           111          6.7             8.4           49.5        7.2        
  Other                            35          8.7            11.3           68.6        5.7        

ROOM TYPE                                                                                           
  Bedroom                         271          5.3             5.4           46.5        3.0        
  Family Room                     118          7.2             8.3           59.3        5.1        
  Living Room                     300          4.7             7.4           36.7        1.7        
  Unfinished Basement             113          7.1             6.5           67.3        7.1        
  Office                            7          6.9             2.9           85.7        0.0        
  Other                            78          9.9            18.6           62.8        9.0        
  Finished Basement                 1          3.6             0.0            0.0        0.0        
  Kitchen                          57          5.2             5.9           42.1        5.3        
  Recreation Room                  21         12.8            18.5           81.0        9.5        
  Dining Room                      45          3.6             2.8           22.2        0.0        
  Play Room                         8          7.5             6.2           50.0       12.5        
  TV Room                           2          3.2             1.3           50.0        0.0        
  Sleeping Room                     1          8.9             0.0          100.0        0.0        
  1st Floor Bathroom                3          1.9             1.0            0.0        0.0        
  Basement Bathroom                 3          4.1             3.4           33.3        0.0        
  Laundry Room Basement            23         10.8            20.3           73.9        4.3        
  Laundry Room Main Fl.             2          8.0             3.7          100.0        0.0        

GEOLOGICAL REGION                                                                                   
  1                               175          8.4            15.1           59.4        7.4        
  2                               372          6.0             7.9           51.9        3.0        
  3                               510          5.3             6.6           42.7        3.3        

BASEMENT SUMP                                                                                       
  Yes                             234          8.0            10.9           59.8        6.0        
  No                              827          5.6             8.5           45.6        3.4        

CLOSED HOUSE                                                                                        
  Yes                             979          6.1             9.0           48.6        3.9        
  No                               82          6.4            10.5           50.0        4.9        

FIREPLACE IN USE                                                                                    
  Yes                              73          7.4            12.4           43.8        6.8        
  No                              988          6.0             8.8           49.1        3.7        


AIR CONDITIONER IN USE                                                                              
  Yes                               2          6.7             0.8          100.0        0.0        
  No                             1059          6.1             9.1           48.6        4.0        

CENTRAL AIR SYSTEM                                            14.0                                  
  Yes                             216      7.3                 7.4           51.4        4.2        
  No                              845      5.8                               48.0        3.9        


TABLE 14

WIC SURVEY STATISTICS BY COUNTY


                                                          PERCENTAGE        PERCENTAGE        
                NUMBER                     ARITHMETIC     OF SAMPLES        OF SAMPLES        
                  OF        ARITHMETIC     STANDARD      GREATER THAN      GREATER THAN      
COUNTY          SAMPLES        MEAN        DEVIATION        4 pCi/l          20 pCi/l         

Adams             14            6.0            5.4            57.1               0.0          

Barnes            33            4.3            4.1            36.4               0.0          

Benson             4            2.6            1.3            25.0               0.0          

Bottineau         16            4.6            1.9            68.8               0.0          

Bowman            12            9.1            6.8           100.0               8.3          

Burke              8            5.3            4.5            37.5               0.0          

Burleigh          65            4.0            4.3            36.9               1.5          

Cass              82            5.0            6.6            42.7               1.2          

Cavalier          22            5.8            9.1            36.4               4.5          

Dickey            10            6.4            3.2            70.0               0.0          

Divide            10            4.8            4.1            50.0               0.0          

Dunn               4           18.6           11.5           100.0              25.0          

Emmons            16            5.7            4.4            62.5               0.0          

Foster            10            3.5            1.8            20.0               0.0          

Grand             61            9.3           14.3            65.6               9.8          
 Forks                                                                                        

Griggs            14            5.2            3.1            42.9               0.0          

Hettinger         18           29.9           38.1            88.9              38.9          

Kidder             6            6.8            4.9            50.0               0.0          

Lamoure           12            2.4            2.0            16.7               0.0          

Logan              5           12.0           15.0            80.0              20.0          

McHenry           26            4.2            2.7            57.7               0.0          

McIntosh           9            4.4            3.3            33.3               0.0          

McLean            10            5.6            6.5            40.0              10.0          

Morton            28            4.7            4.8            28.6               3.6          

Mountrail         10            3.3            1.7            30.0               0.0          

Nelson            12            5.4            4.2            50.0               0.0          

Oliver             2            6.8            2.5           100.0               0.0          

Pembina           18            3.8            2.7            33.3               0.0          

Perkins            2           24.6           13.8           100.0              50.0          

Pierce            14            3.3            3.3            21.4               0.0          

Ramsey            22            3.7            2.5            31.8               0.0          

Ransom            23           13.0           18.9            43.5              17.4          

Renville           8            4.4            2.1            50.0               0.0          

Richland          35            4.5            3.5            40.0               0.0          

Rolette           36            7.0            6.3            55.6               5.6          

Sargent           14            5.6            5.2            42.9               0.0          

Sheridan          22            6.2            6.2            54.5               4.5          

Stark             83            6.3            5.7            62.7               4.8          

Steele             8            2.9            1.5            37.5               0.0          

Stutsman          38            6.0            5.4            60.5               5.3          

Towner             2            2.7            1.7            50.0               0.0          

Traill            16            5.8            2.2            75.0               0.0          

Walsh             47            8.4            7.3            63.8              10.6          

Ward             103            4.6            4.8            39.8               1.9          

Wells             10            4.1            3.1        40.0                   0.0          

Williams          42            3.5            2.5            31.0               0.0          



TABLE 15

WIC SURVEY STATISTICS BY CITY/COUNTY


                                                                        PERCENT        PERCENT      
                                                                        SAMPLES        SAMPLES      
                              NUMBER                      ARITHMETIC    GREATER        GREATER      
                                OF         ARITHMETIC     STANDARD       THAN           THAN        
COUNTY         CITY         SAMPLES           MEAN        DEVIATION     4 pCi/l        20 pCi/l     

Adams                           14             5.99          5.45         57.1            0.0       

             Hettinger          12             4.21          3.49         50.0            0.0       

             Reeder              2            16.70          0.90        100.0            0.0       

Barnes                          33             4.30          4.08         36.4            0.0       

             Kathryn             2             1.60          0.20          0.0            0.0       

             Litchville          2             2.00          0.00          0.0            0.0       

             Oriska              4             3.25          1.31         50.0            0.0       

             Valley City        21             4.49          4.51         38.1            0.0       

             Wimbledon           2             3.20          0.10          0.0            0.0       

Benson                           4             2.63          1.31         25.0            0.0       

             Maddock             2             3.80          0.80         50.0            0.0       

             Minnewaukan         2             1.45          0.15          0.0            0.0       

Bottineau                       16             4.63          1.86         68.8            0.0       

             Bottineau           2             4.10          0.50         50.0            0.0       

             Lansford            6             3.33          1.92         33.3            0.0       

             Souris              6             4.65          1.29         66.7            0.0       

             Westhope            2             6.60          1.90        100.0            0.0       

             Willow City         2             5.70          1.60        100.0            0.0       

Bowman                          12             9.07          6.78        100.0            8.3       

             Bowman             10             8.98          7.42        100.0           10.3       

             Scranton            2             9.50          0.20        100.0            0.0       

Burke                            8             5.29          4.51         37.5            0.0       

             Bowbells            2             2.35          0.25          0.0            0.0       

             Portal              4             5.53          5.19         25.0            0.0       

             Powers Lake         2             7.75          3.55        100.0            0.0       

Burleigh                        65            4.00          4.31          36.9         1.5      

             Bismarck           57            3.04          2.69          33.3         0.0      

             Lincoln             2            3.40          0.60           0.0         0.0      

             Menoken             2           15.25          4.55         100.0         0.0      

             Regan               2           16.40          4.20         100.0        50.0      

             Wilton              2            8.05          5.95          50.0         0.0      

Cass                            82            5.00          6.61          42.7         1.2      

             Fargo              62            4.19          3.24          43.5         0.0      

             Harwood             2            1.85          0.05           0.0         0.0      

             Mapleton            2           14.80          1.30         100.0         0.0      

             Tower City          6           16.68         20.70          50.0        16.7      

             West Fargo         12            4.18          5.86          25.0         0.0      

Cavalier                        22            5.76          9.13          36.4         4.5      

             Alsen               2            3.05          0.15           0.0         0.0      

             Hannah              3            8.10          2.48         100.0         0.0      

             Langdon            14            3.29          3.18          28.6         0.0      

             Wales               2            2.65          0.25           0.0         0.0      

             Walhalla            1           45.00          0.00         100.0       100.0      

Dickey                          10            6.40          3.15          70.0         0.0      

             Ellendale           6            6.97          3.31          83.3         0.0      

             Fullerton           2            2.90          0.10           0.0         0.0      

             Guelph              2            8.20          0.50         100.0         0.0      

Divide                          10            4.77          4.09          50.0         0.0      

             Crosby              8            5.86          3.87          62.5         0.0      

             McGregor            2            0.40          0.00           0.0         0.0      

Dunn                             4           18.58         11.49         100.0        25.0      

             Manning             2           25.80         11.90         100.0        50.0      

Emmons                          16            5.71          4.39          62.5         0.0      

             Hague               2            8.10          2.80         100.0         0.0      

             Linton              8            7.03          5.21          75.0         0.0      

             Pollock             4            2.98          1.42          25.0         0.0      

             Strasburg           2            3.50          1.10          50.0         0.0      

Foster                          10            3.50          1.85          20.0         0.0      

             Carrington         10            3.50          1.85          20.0         0.0      

Grand                           61            9.29         14.27          65.6         9.8      
 Forks                                                                                          

             Grand Forks        55            9.57         14.92          67.3        10.9      

             Larimore            2           12.70          1.70         100.0         0.0      

             Northwood           2            5.10          1.80          50.0         0.0      

             Thompson            2            2.45          0.15           0.0         0.0      

Griggs                          14            5.23          3.07          42.9         0.0      

             Cooperstown         3            4.07          1.03          33.3         0.0      

             Glenfield           3            7.73          0.95         100.0         0.0      

             Hannaford           2            3.25          0.25           0.0         0.0      

             Luverne             2            2.50          0.20           0.0         0.0      

             Sutton              2            2.85          0.65           0.0         0.0      

Hettinger                       18           29.93         38.05          88.9        38.9      

             Mott                6            9.87          8.97          83.3        16.7      

             New England        12           39.96         42.78          91.7        50.0      

Kidder                           6            6.75          4.90          50.0         0.0      

             Dawson              2           13.20          2.40         100.0         0.0      

             Tuttle              4            3.53          1.38          25.0         0.0      

Lamoure                         12            2.35          1.99          16.7         0.0      

             Edgeley             4            2.75          2.37          25.0         0.0      

             Kulm                2            2.80          0.20           0.0         0.0      

             Lamoure             4            1.40          1.39           0.0         0.0      

             Marion              2            3.00          2.40          50.0         0.0      

Logan                            5           11.96         14.97          80.0        20.0      

             Gackle              2            4.25          1.85          50.0         0.0      

             Napoleon            3           17.10         17.47         100.0        33.3      

McHenry                         26            4.20          2.69          57.7         0.0      

             Deering             6            3.03          2.61          50.0         0.0      

             Karlsruhe           4            3.88          2.48          50.0         0.0      

             Towner              2            2.50          0.60           0.0         0.0      

             Upham               2            7.75          0.35         100.0         0.0      

             Velva              10            4.36          2.79          60.0         0.0      

             Voltaire            2            5.75          0.05         100.0         0.0      

McIntosh                         9            4.44          3.30          33.3         0.0      

             Ashley              5            3.32          2.83          20.0         0.0      

             Wishek              2            2.70          0.40           0.0         0.0      

             Zeeland             2            9.00          1.40         100.0         0.0      

McLean                          10            5.62          6.53          40.0        10.0      

             Benedict            2            3.40          0.40           0.0         0.0      

             Butte               4            7.93          9.53          50.0        25.0      

             Riverdale           2            3.80          3.20          50.0         0.0      

             Underwood           2            5.05          1.45          50.0         0.0      

Morton                          28            4.69          4.82          28.6         3.6      

             Huff                2            2.70          1.50          50.0         0.0      

             Mandan             26            4.84          4.95          26.9         3.8      

Mountrail                       10            3.29          1.66          30.0         0.0      

             New Town            2            4.15          0.15          50.0         0.0      

             Parshall            4            2.58          1.08           0.0         0.0      

             Stanley             4            3.58          2.18          50.0         0.0      

Nelson                          12            5.43          4.24          50.0         0.0      

             Aneta               4            0.40          0.00           0.0         0.0      

             Lakota              5            9.44          3.15         100.0         0.0      

             McVille             2            1.95          0.25           0.0         0.0      

             Michigan            3            4.40          1.57          33.3         0.0      

Oliver                           2            6.75          2.45         100.0         0.0      

             Hannover            2            6.75          2.45         100.0         0.0      

Pembina                         18            3.80          2.70          33.3         0.0      

             Cavalier           10            4.11          2.86          40.0         0.0      

             Drayton             6            4.83          2.65          33.3         0.0      

             Hensel              4            2.00          0.86           0.0         0.0      

Perkins                          2           24.60         13.80         100.0        50.0      

             Lodgepole        8  2           24.60         13.80         100.0        50.0      

Pierce                          14            3.31          3.27          21.4         0.0      

             Barton              2            2.40          0.20           0.0         0.0      

             Rugby              12            3.47          3.51          25.0         0.0      

Ramsey                          22            3.67          2.49          31.8         0.0      

             Crary               4            1.88          1.19           0.0         0.0      

             Devils Lake        16            4.26          2.62          43.8         0.0      

             Hampden             2            2.55          0.05           0.0         0.0      

Ransom                          23           13.02         18.88          43.5        17.4      

             Enderlin            4            3.70          0.81          25.0         0.0      

             Lisbon             15           18.77         21.23          60.0        26.7      

             Nome                2            1.20          0.80           0.0         0.0      

             Sheldon             2            0.40          0.00           0.0         0.0      

Renville                         8            4.38          2.09          50.0         0.0      

             Mohall              4            3.45          2.07          25.0         0.0      

             Tolley              2            3.95          1.35          50.0         0.0      

Richland                        35            4.55          3.52          40.0         0.0      

             Fairmont            2            4.40          0.20         100.0         0.0      

             Fairmount           6            4.62          4.18          33.3         0.0      

             Great Bend          2            8.30          1.10         100.0         0.0      

             Hankinson           4            1.50          0.74           0.0         0.0      

             Wahpeton           15            5.61          3.74          46.7         0.0      

             Wyndmere            6            2.67          1.40          16.7         0.0      

Rolette                         36            6.96          6.31          55.6         5.6      

             Dunseith           14            8.34          7.92          71.4        14.3      

             Rolette            10            4.23          3.99          30.0         0.0      

             Rolla              12            7.63          4.88          58.3         0.0      

Sargent                         14            5.58          5.17          42.9         0.0      

             Forman              4            9.50          6.37          75.0         0.0      

             Geneseo             2            4.65          1.35          50.0         0.0      

             Gwinner             6            4.60          4.21          33.3         0.0      

             Stirum              2            1.60          0.70           0.0         0.0      

Sheridan                        22            6.24          6.18          54.5         4.5      

             Denhoff             2            1.05          0.65           0.0         0.0      

             Drake               4            3.10          1.71          50.0         0.0      

             Goodrich            2            0.95          0.05           0.0         0.0      

             McClusky           14            8.63          6.54          71.4         7.1      

Stark                           83            6.33          5.69          62.7         4.8      

             Dickinson          71            6.07          5.40          59.2         2.8      

             Gladstone           2           11.55         10.45          50.0        50.0      

             Lefor               2            8.65          3.05         100.0         0.0      

             Richardton         10            6.63          6.04          70.0        10.0      

Steele                           8            2.91          1.49          37.5         0.0      

             Finley              4            3.55          1.26          50.0         0.0      

             Hatton              2            1.10          0.00           0.0         0.0      

             Hope                2            3.45          1.15          50.0         0.0      

Stutsman                        38            5.98          5.37          60.5         5.3      

             Buchanan            6            4.32          0.55          66.7         0.0      

             Eldridge            2            2.45          1.55           0.0         0.0      

             Jamestown          22            7.55          6.39          68.2         9.1      

             Kensal              4            3.53          2.48          50.0         0.0      

             Streeter            2            4.45          2.95          50.0         0.0      

             Ypsilanti           2            3.70          2.40          50.0         0.0      

Towner                           2            2.65          1.65          50.0         0.0      

             Sarles              2            2.65          1.65          50.0         0.0      

Traill                          16            5.80          2.20          75.0         0.0      

             Mayville            9            5.16          1.44          77.8         0.0      

             Portland            7            6.63          2.67          71.4         0.0      

Walsh                           47            8.44          7.30          63.8        10.6      

             Forest River        2            3.15          1.15          50.0         0.0      

             Grafton            31            8.43          7.15          58.1         6.5      

             Lankin              2            4.20          0.60          50.0         0.0      

             Minto               8           12.00          9.24          75.0        37.5      

             Nash                2            4.10          0.00         100.0         0.0      

Ward                           103            4.55          4.78          39.8         1.9      

             Burlington          2            9.15          2.55         100.0         0.0      

             Donnybrook          2            3.60          1.10          50.0         0.0      

             Douglas             2            8.35          2.65         100.0         0.0      

             Glenburn            2            3.45          1.45          50.0         0.0      

             Kenmare             6            4.25          1.64          33.3         0.0      

             Max                 2           13.55          2.95         100.0         0.0      

             Minot              75            4.47          5.09          38.7         2.7      

             Ruthville           2            0.95          0.15           0.0         0.0      

             Sawyer              4            4.10          3.35          50.0         0.0      

             Surrey              6            2.28          0.94           0.0         0.0      

Wells                           10            4.05          3.09          40.0         0.0      

             Fessenden           2            5.65          0.85         100.0         0.0      

             Harvey              4            5.70          3.62          50.0         0.0      

             Heaton              2            2.05          0.65           0.0         0.0      

             Sykeston            2            1.15          0.25           0.0         0.0      

Williams                        42            3.53          2.55          31.0         0.0      

             Alamo               2            8.20          0.90         100.0         0.0      

             Ray                 4            4.30          2.88          50.0         0.0         

             Tioga               4            4.10          3.72          50.0         0.0      

             Williston          32            3.08          2.01          21.9         0.0         



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