Called 8 firms, 4 have responded with estimates so far.
Range is $5600 for the guy who helpfully listed the sludge disposal as an unspecified "extra charge" (according to the other firms, that's about half the cost of the job. Nice try, though.), to $10,800 for an honest full job.
The winner is probably going to be the guy who came in at $10,500, but *including* a foot of top-soil, raking, seeding, and mulching. He's also the only one who noticed that the permit was wrong (it specifies 14' instead of the 16' that is actually required for 3 drains), and he was the only one who took the initiative of calling Miss Dig for us (they map out water lines, gas lines, etc with flags for free). No money down, too: I don't pay unless I'm happy. That goes a long way in my book.