TABLE OF CONTENTS The procedures in this chapter are intended for communities of 2500 population or less. The basic objectives for any land treatment system are the same regardless of size, however, the design of small systems should include special emphasis on the ease of operation and on minimizing construction and operating costs. Most communities in this size range cannot hire full-time treatment plant operators, and the treatment system must be capable of providing consistent reliable treatment in the absence of frequent attention. In general, most treatment systems that meet these objectives are nonmechanical and have no discharge to surface waters.
The concepts discussed in this chapter include:
Large-scale septic tank and in-ground disposal systems
Small-scale applications of the basic land treatment systems (SR, OF, RI)
Constructed wetlands and other innovative use of the soil ecosystem for wastewater treatment
The procedures for planning and design of small systems are similar to but less detailed than the requirements for large facilities as described in Chaps. 6 through 12. Maximum use is made of local expertise and existing published information. The local Natural Resources Conservation Service (NRCS) staff, the county agent, and local farmers can provide assistance and advice. In effect, the procedures described in this chapter for SR, OF, and RI systems reduce the cost and complexity of site investigation, planning, and system design by increasing the magnitude of the safety factors involved. This approach is typically acceptable for most small systems. However, if land costs are high or...
