Septic fields, am I being ripped off?

Update on this.

We had a few companies come give us quotes, and we decided on a local company, who quoted $11,000 for a Type 2 system, but which uses a product called Envirotubes. Basically each pipe is $300, but the amount of space they use is reduced to 1/4 the size of a regular septic field. That works great for us, because the only area far enough away from the 3 surrounding wells and a creek in the back in right behind the shop, in a small clearing between some huge 100+ year old trees. I'd rather not take the trees down, and the only way to do so is to use this system.
So far they've shown up on time every day, worked 9 hour days, and have treated us very good. No deposit needed, he does things the old fashioned way of, "I do the work, you pay when it's done." He even dragged my 1969 Dart parts car into the back for me with his little hoe and parked it where I wanted it.
The only problem they've run into is where the new tank is going. It's right behind the house, and we discovered why we're on a slab and don't have a crawl space. There is EXTREMELY solid rock about 4 feet down. Some "rock expert" the contractor knows said this type of extreme compressed rock is only found where a glacier was once sitting, about 15 kms wide.
The contractor and his worker used a hammer drill and jackhammer for 6 days straight, 9 hours a day. This stuff would not break! It basically turned to powder and rounded off the jackhammer bits. They couldn't use the jackhammer on the end of the excavator because it was so close to the house, they could crack the foundation. They even considered bringing in a company who uses dynamite, but they would have to blanket the windows and hope they wouldn't blow out.
So, yesterday they finally got it deep enough to bring in the tank. They had to crane this massive concrete tank over my house which was stressful enough. At least it's finally in.