After many google searches I give up. Is there a special ground strap for the connection of the well casing to the ground wires of the pump wire circuit? My well cap is made of some sort of light alloy so it is not a candidate, nor does it have a grounding screw on it anyway. Drill a hole in the well casing for the bond?
I have been a licensed electrical journeyman for years, and I have yet to hear of anybody try to make any part of their electrical system a better ground to Earth than anything the power company installs. This is a recipe for disaster for attraction to lightning. The well cap just needs to have a simple ground strap bonded from the grounded conductor, not the pump or from a ground rod ever! The conductor being used to wire the well should have the conductor run with it if the electrical inspector requires it. The electrical circuit will pop the breaker using the neutral if the pump goes bad, the pump has the strap inside of it so it doesn't need additional grounding, the cap does though in some areas so the inspector maybe feels as if he did his job. Ground rods are an absolute bad thing and it is only because you may create a better ground that you do not want for the reason of lightning.
If a plumber installs a pipe ground that ties to a bonding system to an electrical panel, that really isn't their job, it is first the electrician's, as well, the electrical bonding and grounding of any well pump system the installer should be qualified to do so, and hold a license to install, like the licensed HVAC guy, he has to hold electrical credentials or hold a special license that would allow them to electrically connect the system,. The rule of thumb is to ground what is necessary but not make the resistance lower than it already is. If there is any indicating factor that would lead an electrician to believe that the power company's grounded neutral or center tap of the distribution transformer is not grounded effectively, nobody has any right to go grounding their home with a rod, reground their breaker box, meter can, swimming pool, or well better than the distribution system is.
I'll tell you all why:
The power company is to install (2) 10' copper clad 3/4" ground rods within 6 feet of any utility pole that services the home or the area. If the system is an underground system (my specialty), the transformer pad is to be grounded with two 10 foot ground rods, completely below grade at the depth of the trench which is a bare minimum of 24 inches from the grade for direct buried cables, or, 30 inches for conduit. The transformer pad by NEC code should have a completed ring bus of a minimum of a 1/0 copper bare stranded wire all the way around the transformer with two tails coming from the ground connected with mechanical tank grounds (threaded servits) to the case of the transformer. The center tap of the secondary side of the transformer is to bond with a heavy gauge multi layered copper graounding strap to tie the Earth to ground for safety of the resident, as well, for a path for the lightning arrestors on the high side (medium voltage elbows or station type lightning arrestors to safely discharge to ground)
All system components in a home are to be bonded in the panel to the neutral bus for the simple fact that the neutral makes it's way back to the transformer as a return. If the neutral wire is loose or burnt clear, the end result would be a safe path through the ground back to the source for return, which is usually through ground the imbalance load of the system only.
All components to be grounded, such as swimming pools, jacuzzis, etc. are not to have physical ground rods punched to the earth next to the pool because it makes the pool an attractant to lightning. The pool's components should be grounded with mechanical lugs, (for instance an above ground pool) one #10 or #8 green jacketed conductor, tied to every support beam, uncovered, then, tied to the mechanical lug on the pump, and connected to the connections thereafter place after place and connected to the neutral/ground bus. These connections all have resistance, and it is vital that the ground resistance measured from ground to the neutral is more than the ground connection at your box tested across the neutral.
The ground connection from the pool will have several connectors along the way from the breaker box to feed it's ground, then, back from the pool to the neutral/ground bus again. The added resistance assists with eliminating the pool from being struck by lightning.
The same goes for pipes, but, in most cases, cast iron or metallic pipe that is direct buried into the home, especially copper is grounded all at the same place, and the power company grounds should equal or be a better ground to be a less resistance to be the attractant for the lightning instead of a home or pool since it has the needed protection to safely discharge the bolt, a swimming pool does not , as well, kids swim in a pool.
If we carry a ground from our well back into our home, some wells are 300 feet deep. This would be a massive hazard as pipes, electrical boxes and outdoor receptacles would be a better choice for the bolt of lightning to hit, possibly killing a pool full of children, etc. Use your heads before you ground in a fashion it isn't supposed to be, like adding ground rods when they are not necessary. We have all of these rules for a reason, too bad they don't tell us why, that is why we go to school or have very extended bonified apprenticeship programs to follow.. A simple resistance check could be done but, a ground resistance meter is supposed to be used by the power company, or, is supposed to be used by the electrical contractor/personnel before trouble is started.
To check the resistance in the box, to the source, there may be an exposed ground next to the pole, or a down ground on the pole. The ground resistance meter is connected to this and also grounded a distance away, usually where other rods are driven. If a water pipe has a better earth than the power's ground, then by connecting them together in the street usually eliminates the issue. Like I said, connections add resistance and the connections are vital because they are engineered into the formula when the designs are studied originally . If lightning protection is used, it means there is either a massive change in topography, or, the ground has saturation making it a well suited spot to attract cloud to ground lightning.
I have one of these meters at my disposal, it is vital to use these when homes or any other dwelling is built in a sandy area. Some poles or transformer pads need excavation to bring the ground to a good spot that is actually an accepted and approved level to discharge lightning through a set of lightning arretors, and high voltage bleed off from shielded cables since they always slowly dissipate to the grounded sheath and it is very important to follow these guidelines. DONT GROUND MORE THAN NECESSARY. The fault current relies on a grounded conductor to be used for the breaker to pop, nothing more, but, it has to lead from your breaker box, not from a driven ground ever because a voltage drop would be created and the breaker is designed to open at the rated voltage, when voltages are reduced amperage climbs, netting the same wattage, but, the breaker isn't designed for wattage, it's designed for amperage at only a given voltage.
Marc