Partial preview of the text
Download Ngwa general drilling exam and more Exams Construction in PDF only on Docsity!
NGWA GENERAL DRILLING EXAM (ACTUAL 2025) QUESTIONS AND VERIFIED REVIEW GUIDE Artesian Pressure is generally... ... aresult of gravity and confining beds. What is true about the origin of rocks? 1. Sandstones were once sand deposits and could have been river sand, beach sands, or dune sands. 2. Some limestones contain fossils because they were once the mucky bottoms of shallow seas. 3. Shales were once clay beds. Sedimentary formations may reach depths of a mile or more. Chain and drive shaft guards... ... Should be kept in place. In performing adjusts to components that are driven by clutches and/or drive shafts, you must... ... Shut unit down and lock out before adjustments are made. (T/F) A drilling fluid should do all of the following: 1. Cool the bit. 2. Promote longevity. 3. Remove cuttings from the bit surface. 4. Transport cuttings to the surface. 5. Plug lost circulation zones. 6. Promote hole stability. True. A good preventative maintenance program will create... ... operators who have a thorough understanding of equipment. Drilling rigs should be fueled... ... in the morning before starting the drill. Drill rig or pump hoist engines should not be started unless... ... clutches are disengaged and gears are in neutral. In proper well design... ... well screen intake velocity should be less than 1'/second Reduced yield from a water-bearing formation can be caused by... ... screen incrustation. The diameter of a screen is not a critical factor in the specific capacity. Double the diameter of a screen generally increases the specific capacity by what percent? 7% to 10%. When drilling in an unfamiliar area, the collection of samples... ... can enable the ground water professional to correlate formations from one area to another. A well screen... 1. Is a filtering device. 2. Permits water to enter the well from the saturated aquifer. 3. Precent sediment from entering the well. (T/F) Gravel-packed wells should be sealed at the top of the gravel pack as well as in the annulus. True. (T/F) Dry cement may be mixed with water in the annulus to form an acceptable surface seal. False. Pressure grouting requires that the grout must be... ... under sufficient pressure to drive it into the zone to be grouted. When only 40' of cement is required to grout the surface casing, one can achieve a good seal by... ... placing from the bottom up using a tremie grout pipe. ... the pump starts at 40 and will shut off at 60. One gallon of water weighs how many pounds? 8.34 Your well is 6" diameter, 150' deep, and has swl of 50'. How many gallons of water are within this well column of water at the very bottom of this well? 150 gal. How many galloons are in a cubic foot? 7.48 Water system pressure is expressed in? PSI (T/F) Ground water, like surface water, has a tendency to flow downhill. True. The three main types of rock are... ... igneous, sedimentary, and metamorphic. Water would be least likely found in what geological formation? Granite. (T/F) More than 90% of our nation's fresh water is underground? True. Prior to setting the rig, you should... 1. Make sure there are no overhead power lines within at least 20' of the mast. 2. Locate all buried materials. 3. Verify you are on the right property and meet the correct setback requirements. Confined space entry rules require... 1. Shoring of trench walls over 4' deep. The best method to drill a domestic water supply well in cavernous hard rock would be... ... cable tool. The advantage(s) of reverse circulation drilling include(s)... ... porosity and permeability are relatively undisturbed. The following drill rig is the least acceptable to drill through a consolidated shale in sandstone formation... ... a bucket rig. (T/F) Cable tool rigs are advantageous for the following reasons: 1. Straightness of well. 2. Minimum maintenance. 3. Economical Use. True. (T/F) Drilling mud viscosity can be accurately estimated by visual inspection. False. One cubic foot equals... 7.4805 gallons The difference between static water level and pumping water level in a well... ... 1S called the drawdown. (T/F) Well development procedures should be able to clean the well so the sand concentration in the water is below the maximum allowable limit set for particular water use. True. Well drilled using guar gums and several polymers can achieve better development by using mixes in the development water. Sodium or calcium hypochlorite. 
