I found it

At long last, I have finally found our septic tank! Funny thing to lose huh! Well we don't have a mushroom on the top of our tank, so it really is potluck as to where it might be. The previous owners weren't being at all helpful in where the emptying point was. We had 3 different companies come and see if they could find it, but no such luck. The last guy suggested we get in a digger to find it - yeah right! The biggest problem is that we have so much volcanic rock around the place that when you test for it, you aren't sure if you have hit rock or the top of the tank. Today I found it, and the earliest anyone can come to empty it is Monday.