REPORT OF INVESTIGATIONS No. 41


abandoned to decentralize pumping and to thus prevent excessive drawdowns which were limiting production of water. The control of water levels was considered necessary also as a precaution against salt-water encroachment. Pumping from each of the other wells in the field was regulated for the most efficient production from the aquifer within the cone of influence. Water-level records, shown in figure 19, of an abandoned well about one mile from the center of pumping show the effectiveness of this program.

-J
W 75
  bi     Water level affected by
  80so   near-by pumping wells
  - 85
  w90
  S95
M 100*
I
w  105                                 I
ZU- 0
LU  115 

   120
1~  125
   <  1951 11952 1953 1954 [1955T1956 1957 1958 1959 1960 11961 1'962 1963

 Figure 19. Graph of water levels in observation well 008-537-332 near the center
   of the International Paper Company well field for the period 1951 to 1963.

   In January 1964 the paper company was producing water from 21 wells in the Floridan aquifer and 10 wells in the water-table aquifer. These wells were pumping an average of 15 mgd, of which about 13.5 mgd were from the Floridan aquifer. At this time the water level in the Floridan aquifer under pumping conditions was about 184 feet below mean sea level at the center of pumping and 100 feet below mean sea level on the east edge of the field. These represent drawdowns of about 200 to 120 feet since pumping began in 1930. Although this is a considerable drawdown, the pumping level in the field was essentially stabilized at this level. Minor fluctuations (fig. 19) were caused in part by seasonal variations. in pumping from neighboring well fields. The major recoveries shown on this graph indicate periods when pumping from wells near the observation well was stopped temporarily or wen pumping from the entire field was stopped.