Bought a cottage late this past fall. The previous owner had uncovered the septic system - I think so prospective purchasers could inspect it. We were only at the place once before the snow fell and never noticed it was open to the elements. This past weekend we went up and quickly found out that the plumbing was blocked. A bit of investigation brought me to the tank. Since it was uncovered I was able to open it up - it is like an ice cube.
Any thoughts on thawing it out? Someone has suggested using a steam pressure washer. Another idea is a immersion or bucket heater of some type.