I have a sump pit which water from around the foundation flows into. Before we moved into the house a new septic system and field were installed. They also installed a new pipe from the sump pump through the basement wall which continues outside underground about 10' from the house and then turns downward. We had a very heavy rain for an extended period a while back and the sump pump ran continuously. I noticed that water was bubbling up from the ground where the pipe runs. Then recently a sink hole started to form in the yard where the pump turns downward. We have very sandy soil so I tried to dig down further to see where the pipe ends but I got to 4' plus and the pipe still continues downward. I do not know how to continue with this dilemma as I am afraid that if I fill the hole it will appear again.
Is this a normal system for a sump pump exhaust with no city sewer?
Can someone tell me how this system is supposed to work?
I am at a wall as to what to do or how to continue. I thought about digging a little deeper and then filling the whole thing with stone.?.
Any help would be greatly appreciated as how to continue or how this thing is supposed to work.
Thanks in advance.

