Bu!letin No. f.4


 In this section, the definitions o the extent of confining, injection and monitor zones are those made by the consultant companies during drilling. The consultants chose the placement ol monitor zones based on their definitions, so the water-quality dala from the monitor zones are analyzed and discussed in terms of those delinitions,

 However, the consultants' hydrogeological interpretations often differ from those of the Florida Geological Survey (FGS), Characteristically, their definitions of confinement cover a broad interval. Available data allowed FGS geologists to better delineate confining zones within the lower Floridan aquifer system. These data allowed the definition of three confining zones: the middle confining unit, the lower Avon Park confining zone, and 1he glauconite marker bed. These units are discussed in the Hydrogeology of the Middle Confining Unit of the Floridan Aquifer Syslem and the Hydrogeology of the Lower Floridan Aquifer System. Plate 3 shows the confining zones delineated by the FGS geologists.


 In addition to the definitions of confining, injection and monitoring zones, the consultants' reports provided background water-quality dataThe Bureau of Drinking and Ground Water Resources ol the DER provided the lime series water-quality data taken from the monitor welis at each site. Lithologic descriptions were done by FGS geologists. Porosity, induration, and permeability descriptions were based on visuaL inspection of cuttings and cores, and were supplemented by geophysical log data, whenever possib le,


 The description of samples involved determining lithologies and physical properties. Physical properties determined for each sample include color, porosity, permeability, grain size, induration, cement type, sedimentary structures, accessory minerals, and presence or absence


of fossils- These descriptions are a part of the FGS well-file database. General lithoiogies are illustrated on Plates 1, 2, and 3.


 The lithologic descriptions were also correlated wkth geophysical logs (for example, see Plate 1), When possible, porosity values calculated from sonic logs were used to supplement the descriptions.


 Monlor zone water-quality data were examined to ascertain if there has been any migration of injection or formation walers due to pumping. Vertical migration of injection waters would be indicated by falling TDS and chloride concentralions, and by rising TKN concentratons. If verti. cal migration or contamination occurred, these trends would be most prominent in dala Irom the lower monitor zones.