30 Years of Proven Septic System and Excavation Experience

For over 30 years, Schaefer Grading and Excavating has been family-owned and -operated by Darrell Schaefer. We specialize in the design and installation of privately-owned, on-site wastewater treatment systems. 

We are also able to satisfy the need for specialized grading and excavation for any type of new construction or existing projects.


We have systems for new construction or replacements for failing systems including

  • Mound systems
  • At-grade systems
  • Aerobic systems
  • Soil testing
  • Septic inspections
  • Sand-filter systems
  • In-ground pressure systems
  • Conventional septic sysemts
  • Newer system repairs

Mound Systems

A mound is a covered, above-grade wastewater treatment system. It also recycles the treated water back into the environment. The mound receives septic tank effluent, which is distributed by a pressurized pipe network in the mound over a layer of coarse sand for treatment before traveling into the soil under the mound. The system is useful for sites with shallow groundwater, or those with slowly permeable soils. The mound system follows your septic tank and adds an additional pump chamber. Septic tanks with soil absorption systems are the most commonly used wastewater treatment systems in rural and suburban areas. Schaefer Grading and Excavating is your reliable source for laying the groundwork for your septic tank system.

Do You Need a Mound System?

A certified soil tester will complete a detailed analysis of your soil characteristics, along with other site limitations, including setbacks, slopes, etc., to determine the type of system required for your lot. 

The soil tester is looking for a depth to a “limiting factor,” such as high groundwater or high bedrock. The current Wisconsin administrative code ILHR 83 mandates a 3-foot vertical separation between the bottom of the soil absorption system and high groundwater or high bedrock.

Sewer Systems

All septic systems will fail at one point, and you will have to replace the system regardless of what type of system you require. Schaefer Grading and Excavating is here to help you dig up and replace your sewer system.



Some signs of a failing system include sewage backup into your home. However, a backup can also just be the result of a blockage somewhere in the line between your home and septic tank. Another possible sign of failure is the smell of sewage outside your house.

If the liquid effluent cannot soak into the soil surrounding the leach field, sewage may back up into the system and overflow into your house, or puddle on the surface of the ground. There are several potential causes for this problem, all of which we can help you with.

Common Signs

Poor soil conditions and faulty design or installation

A leaching system placed in unsuitable soil, a system that is too small for the home it serves, or even an improperly constructed system may lead to early failure.

Soil clogging

If sludge or scum is able to get into the distribution box, and from there into the leach field, the soil will become clogged. If this happens, liquid will no longer soak or percolate into the soil. This condition can be caused by broken baffles in the septic tank that allow sludge or scum to escape. Failure to pump your tank can also lead to a situation where the sludge and scum overwhelm the baffles.


Physical damage

Trucks or heavy equipment can render the system inoperable when passing over the system, as they can damage pipes and joints.


The roots of trees or bushes planted too close to your system can sometimes enter and block the pipes. Removal of the plants and clearing the pipes is usually required.

Maintaining Your System (The Don’ts)


dispose of cooking oils or grease down the drain


 use your toilet as a wastebasket!!! Do not flush diapers, wipes (biodegradable or not!), tampons, condoms, cigarette butts, coffee grounds, egg shells, kitty litter.


put chemicals down your drain – adding chemicals (household cleaners to toxic chemicals i.e. paint, solvents, pesticides) kills bacteria.


use of anti-bacterial household cleaners, used in excess, these can destroy bacteria.

Schaefer Grading and Excavating Franksville, WI 53126
262-835-4408, 414-791-3925