c tank pumping, pump maintenance, control system inspections, and SO If seepage should occur around the base of the mound, repair is a simple matter. Remove the top soil from the mound at the edge of the area of seepage. Till the natural soil around the area of the leak, work in more fill material, and extend the mound a bit. The exten- sion should have about 6 in. of fill near the mound and 6 in. of top soil cover. Should severe clogging occur, refer to Chapter 8 in Part III. LAND APPLICATION Application Land application of liquid waste allows disposal in a manner that allows the water and nutrients to be used by plants. There are both significant advantages and disadvantages to this disposal method. The primary advantages are that it might save you money on your 134 ONSITE WASTEWATER DISPOSAL water or electric bill and that it creates valuable resources from waste products. Disadvantages include susceptibility to freezing in the winter, necessitating a backup disposal system in colder cli- mates, and the possibility of contamination of the immediate envi- ronment with disease-causing organisms. Health departments don't look favorably on that latter condition. There are perhaps five categories of land application techniques: flood irrigation, furrow irrigation, sprinkle irrigation, trickle irriga- tion, and shallow subsurface irrigation. The first four techniques involve applying sewage effluent to the surface of the ground. Therefore, these techniques cannot be used year-round where freez- ing temperatures commonly occur in the winter. Furthermore, whenever sewage is exposed, it constitutes a health hazard both because of its potential for direct contact with humans and pets, and because of its potential for attracting vermin, flies, mosquitoes, and other such undesirable critters. So where sewage is to be exposed, it must first be disinfected. A detailed discussion of disinfection is contained in Part III. Meanwhile, it is sufficient to say that disinfec- tion systems can be a pain to maintain. A third problem