Driller gave up my Geothermal Well

[eureka]

The plan was to drill to 450 feet(the hope was 30 feet of casing before rock because of another nearby well with that distance) 75 feet of casing was inserted but then the drill operation got stuck in clay. Compressed air were used (not mud). What now. Is there any possibility to measure the actual depht to rock and perhaps put in more casing. is there any possibility to put the closed loop collector in a open hole controlled by mud
best regards
Eureka

[junkhound]

Well drilling was one of the most difficult tasks for me to learn, and is especially difficult in rock/cobble/mixed geology strata.

If your driller gave up, sounds like they drill with only one type technology that cannot work cost effectively in your mix of strata.

Oil drillers measure and record the strata by various methods, including sonar and setting off charges and measuring the reflected waves. Cost is likely prohibitive however for a residential GSHP application.

Find somebody with an 'old fashioned' cable tool drill rig, that will eventully go thru anything.

It would help to know where you are located. Often a layer of clay, especially if it is blue clay, means a good aquifer lays on top of the clay layer (bottom of old glacier). You could talk to your driller and gshp installer as to flow needed and see what type water flow you could get and install 2 wells - pump water from one and dump to the other 'downstream' .

[eureka]

Thanks for good advices. How big will a cable tool rig be.
Best regards
Eureka

[junkhound]

How big will a cable tool rig be.

Most the smaller ones are on a 2 Ton truck chassis, have seen a few on 1/2T pickups or even trailers.

Anything less than on a 2T are toys. Most 2T are on 4x4 or 6x6 drive systems so can get into most places.

[eureka]

Can I continue on my 100 feet hole with 6'5 casing with the cable tool rig or is it best to drill a new hole

[junkhound]

Yes, if it is straight and perpendicular.

[eureka]

I understand the sediments will be crushed to very fine particles and mixed with water this will be the mud is that correct or ? is it nessesary to have any circulation like a rotary drill or is it nessesary to go down with a tool to emty the well. When drilling in clay is it then nessesary to add casing or can you have an open hole also in clay
Best regards
Eureka