On 1/6/2011 3:32 PM, Doug Turnbull wrote:
> I have been following this thread but may have missed some points. I
> have an abandoned and unused well largely running through Basalt (sp) rock
> with about a thirty foot long steel liner at the top. I have sometimes
> wondered how this would work as a mounting point for a vertical with say
> quarter wave log wires dropped down into the well water and the vertical
> attached to the steel casing. I am not particularly concerned about
> lightning as I have another well three hundred feet away which runs 450 feet
> down and thankfully we get little lightning in this area. No one seems to
> have addressed the performance question.
Many as it really doesn't help the performance. These deep grounds are
for safety and have little effect on RF and particularly verticals. Of
course we often hear of some one who has their vertical right over an
old well and says how great it performs.. Surface or elevated radials
make a great difference, deep grounds do not. The deeper you go the
*less* effect they have on the RF efficency and radiation pattern.
> 73 Doug EI2CN
> -----Original Message-----
> From: email@example.com
> [mailto:firstname.lastname@example.org] On Behalf Of Roger (K8RI)
> Sent: 05 January 2011 21:20
> To: email@example.com
> Subject: Re: [TowerTalk] ground rods and wells
> On 1/5/2011 11:13 AM, jimlux wrote:
>> On 1/4/11 7:20 AM, WA2PUQ wrote:
>>> Correct me, if I'm wrong, but doesn't the well casing only run down to
>>> bedrock, the pump being possibly much deeper in the hole?
>>> If so, even the connected ground and casing might not be of that great a
> This is another ...It all depends. Much of the country, or maybe most of
> if is not mountainous and bed rock is a very long way down so the wells
> do not extend all the way to bed rock. Here bed rock (shale) is only
> about 470' down. On top of that are various layers of sand, gravel, and
> clay. Under that shale are various layers of salt water, crude, and
> other noxious stuff with many spots where that *stuff* is leaking out
> contaminating ground water. BTW Shallow crude is usually sour (contains
> high sulfur content and other *stuff* including bromine)
> You may get good water at 50 feet or 150 feet just a few feet over.
> These various aquifers usually slope, so what you have at 150 feet may
> actually come to the surface only a few miles away, or it could be 20 or
> 30 miles. By the same token, you may have good water for decades and
> then have it turn bad. You may drill a new well and have good water for
> 30-50 years, and it may only be good for weeks.
> These wells have an outer casing as well as in inner one with the
> "point" or points attached to it. These points are gasketed to the
> casing at the top and can be placed series for more capacity. These
> screens are a tube with a network of fairly large holes covered with a
> fine screen. These screens can plug up and in areas where there is a
> lot of lime in the water they can plug up rapidly. The lime can
> sometimes be removed by "acidizing" a well . The acid reacts with the
> lime (calcium carbonate) and dissolves it. Any excess acid is quickly
> neutralized by the lime in the water. Other times the inner casing with
> points attached have to be pulled and the point or points replaced. Then
> again lime collects around the points and it may be necessary to drill a
> new well which is not cheap. A 150' 3 or 4" well is going to run some
> where between $6000 and $10,000 around here. More if there are lots of
> Agricultural wells in the Great Planes and South West may be 1500 feet
> deep or more
> But to comment on the strike where the water from the well was cloudy.
> The lightning may create enough of a mechanical shock (steam or
> magnetic), or electrical impact to actually remove the coating of lime
> on the point and inside the well casing. It *may* also blow the screen
> right out of the point.
> Roger (K8RI)
>> Could be.
>> I'm pretty ignorant on wells and such.
>> I was just wondering what the failure mechanism would be. Is it current
>> flowing from the earth into the pump and up the power wires (or vice
>> versa)? Or something else?
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