CHAPTER 9 WELL DRILLING SUPERVISOR The  Naval  Facilities  Engineering  Command (NAVFAC) invests millions of dollars in water well drilling equipment and the training required to enable the Naval Construction Force (NCF) to meet water well drilling requirements at various locations and conditions throughout  the  world. The    COMSECOND/COMTHIRD    Naval Construction   Brigades   require   all   Naval   Mobile Construction Battalions to maintain an allowance of personnel qualified in water well drilling operations. The Naval Construction Training Centers (NCTC) and Regiments from both Gulfport, Mississippi, and Port Hueneme, California, provide training in water Well drilling operations. The NEC for water well driller is 5707. The means of attaining this NEC is most often through completion of the water well driller course that is offered at NCTC, Port Hueneme, California. This chapter can only provide the basic terminology and procedures used in well drilling operations. The extensive  knowledge  and  skills  required  to  perform  as an effective well drilling supervisor must be gained through  formal  training  and  on-job-training  experience. WELL  DRILLING  SUPERVISOR RESPONSIBILITIES Successful  well  drilling  operations  are  a  direct result of the efficiency of the supervisor and crew. The drilling rig and its controls are not complicated and can be  mastered  in  a  short  time;  however,  knowledge  of  the mechanical operations is only the start and experience is the vital element. Drilling water wells is an art for which there are no hard-and-fast rules; it is an art that requires a good deal of  common  sense  and  improvisation.  The  well  drilling supervisor  must  have  a  general  knowledge  of  the physical  structure  of  the  earth’s  crust  and  the groundwater  resources  within.  Often,  problems  arise  in well drilling, and the well drill supervisor must be able to visualize what is occurring at the bottom of the hole. An  awareness  of  the  conditions  under  which groundwater  occurs  and  of  geologic  conditions  is  a shortcut to the solution of some drilling problems that would otherwise take much time and experience to attain through the trial-and-error method. WATER SOURCES The source of all fresh water upon and in the land areas of the earth is the oceans. Precipitation in the form of rain, hail, sleet, or snow recharges lakes, streams, and underground water. Part of the precipitation that falls upon  land  areas  soaks  into  the  ground  and  under  the influence of gravity is pulled downward until it becomes part of the saturated zone. Water in the saturated  zone is referred to as groundwater  and it is within this zone that wells are developed. Water recovered from beneath the ground accounts for a much larger percentage of our water supply than that from natural lakes or man-made reservoirs. Above the  saturated zone  is a zone identified as the zone of aeration.  This  zone  is  divided  into  three  belts: (1) the belt of soil moisture or plant root zone, (2) the intermediate belt, and (3) the capillary fringe. Neither the  intermediate  belt  nor  the  capillary  fringe  is  capable of producing water in usable quantities because the pores  or  open  spaces  between  individual  particles  are not all filled with water. Water in the zone  of aeration is called subsurface water  and should not be confused with groundwater contained in the saturated zone where all the pores are filled with water (fig. 9-1). The volume of water contained in the  saturated zone is the total volume of the openings in rocks or between the individual grains of sand or gravel. These openings are referred to as the  porosity  of  the  particular material. The   physical   characteristics   of   the   zone  of saturation  can  vary  widely,  depending  upon  the geologic formations of the earth layers; that is, sand, gravel, clay, rock, or a combination of these. This zone may also wary in depth from a few feet to many hundreds of feet. Water may be found within the  saturation zone  in one continuous body or in alternating layers of clay and sand. This all depends on the impermeability  or the permeability of the formations within the saturation zone; for example, while clay may hold a relatively high volume  of  water,  the  openings  between  the  individual particles are so small that they prevent the flow of water. Clay is then said to be impermeable. Confined  between 9-1