home improvement/ old well on property ??

Long story short i just found out i have an old well on my property, the town went to public water a long time ago.
The well is located under my rear patio, my rear patio was made of concrete slabs.
The concrete slab over the well has started to crack and shift a little, to top it off there was a spot that looks like it was patched....my foot went through it the other day, i got my flashlight and discovered it is about 20 feet deep and 4 feet wide.
Keep in mind up until the point when my foot went through the patched spot i did not know there was a well under my patio.
There is water in it, i guess about a foot of water.
What is the cheapest and fastest way to make this safe?
Would it be cheaper to somehow get a new concrete slab poured over the hole?
Would be worth my time and effort to fill it with free fill from construction sites? This idea presents its own problem, it would have to be carried in by buckets from the street and up 10 steps....i have plenty of friends that would help so its possible it could be done in a weekend.
Any ideas or input is appreciated, im located in york pa if anybody recomends any concrete workers

 

Are you sure it is a well? and not a old septic tank?

If it's a septic tank it will be much smaller and easier to fill. An old school well is typically pretty deep.

 

I checked with my neighbor, he said its a well. He has one in the same spot under his patio. The sides are lined with brick and stone, i think a old septic hole would not be lined? Whether its a well or septic i need a solution asap, i have a 3 year old and a dog, plus we have to walk past it to get to our cars everyday

 

Keep the well, the terrorists may poison the public water supply and then you will still have water.

 

1) rebuild it into a wishing well
2) people throw in money
3) profit!

If it were me I would try to rebuild it as a raised well and put a cap on it for safety as an alternate water source but have the water tested first.
If it's loaded with contamination, bury it or fill it in whatever.

 

It's a rainwater catchment

 

Probably an old surface well. What's the water table like? Fill it in with gravel, 3/4" crushed preferred for good drainage, a new top & you're good to go.

 

Not sure where you're located OP, but please keep in mind that most States regulate how wells are abandoned.

For example, in PA it is regulated by DEP (click link below). I'd do a search online for your State's well abandonment procedures before you start filling it in.

http://www.dep.state.pa.us/dep/deputate/watermgt/Wc/Subjects/SrceProt/ground/sympos/GrdMonitor-chap7.htm

 

OP , in my opinion it's most likely a rainwater cistern like this

http://www.oldhouseweb.com/blog/cisterns-historic-water-convservation/

 

Could be a cistern, though having water in it with a concrete slab over it for who-knows-how-many -years means it's tapped into the shallow groundwater aquifer. I've seen wells shallower than this in the far eastern coastal plain, some only 10' deep, still being used today.

My suggestion is that the OP should follow his State's well abandonment procedures, more out of safety concerns than anything. Usually this simply entails clean aggregate fill with a concrete or bentonite cap several feet thick.

 

Thanks for the links, ill check them out
My next question would be how much money am i looking at spending to get the concrete slab replaced? It is about 5 x5 feet

 

Downspouts would be tied into it and possibly the perimeter drain if there is one , that's how rainwater carchment works

 

First figure out exactly what it is. Something like that around here would be a cistern. In Texas it most likely would have been an old hand dug well. Good luck to you.

 

20ft deep by 4ft wide?
That's about 29 yards.... It needs to be filled, but you aren't going to do it with 5-gallon buckets in a weekend.
That's more than 3 full "cement mixers" if you fill it with concrete.
It's nearly 40 tons of material if you fill it with dirt.

And even if you were to attempt to fill it with buckets, you would have no way to properly compact it as you fill it. The best you could do would be to fill it partway with water, dump in a bunch of dirt until the dirt breaks the surface of the water, and repeat that every few weeks. It still won't be properly compacted, but it'll be better than just dumping in dirt.

 

I would just repair / replace the slab

 

Slab repair is the best and easiest fix. Would NOT have it filled-you never know, you might decide to use it at a later date.
Did they use REBAR in the initial cover up? Be sure to use it this time. It might eventually crack, but will NOT form a hole.

 

That hole is HUGE!!

 

Geometry is a bitch.

20ft by 4ft? Doesn't sound that big.

A 4ft circle has an area of over 39 square feet.
Multiply by 20ft deep and you've got almost 800 cubic feet.
Divide by 27 and you're down to 30 cubic yards.

Typical concrete truck is 9 yards.

Dirt is roughly 3000 lbs/yard.
30 yards at 3000lbs is 90,000lbs
The Tacoma is overloaded with 1,000 in the bed, so that's at least 100 trips with the truck, plus hauling it into the yard.

Time to pay someone to determine what it is and make it safe properly. It could be an abandoned well, it could be a drainage sump, or it could be a cistern.

 

Generally when sites went to public water or a well was drilled the old wells had to be filled. Rocks were fine the ideal was to make it safe to keep kids,dogs etc. from falling in. I would research it at your town office discreetly first before going any further.

 

Agreed. Ultimately there are not going to be any receptors in an area where everyone is on public water, so groundwater contamination from surface water run-in is not much of an issue. The main concern is safety, and filling the well/cistern with rock/aggregate is probably the best approach. Simply putting a slab over it is just making a problem for someone else down the road, or even you or your family if the job isn't done right.

Definitely look into your State/local regulations regarding abandoning wells properly, same as you would look into building codes before constructing an addition onto your house. There's good reason why those regulations exist. Most "well" abandoning regulations include pretty much any substantial hole in the ground, including "dry wells", which would include cisterns.