TABLE OF CONTENTS The factors described in Chaps. 4 and 6 regarding groundwater conditions, soil properties, and other site factors not only influence the initial site selection and concept feasibility decisions but are critical for the final system design. The investigation and testing procedures that are commonly used to obtain these data are described in this chapter.
As with all other engineering projects, the type of test required and the specific procedure are relatively easy to describe. The more difficult decision is deciding on how many tests, and in what locations, are adequate for a particular project. Too little field data may lead to erroneous conclusions while too much will result in unnecessarily high costs with little refinement in the design concept. Experience indicates that where uncertainty exists, it is prudent to adopt a conservative posture relative to data-gathering requirements.
Table 7.1 is a flowchart which presents a logical sequence of field testing for a land treatment project. When possible, available data are first used for calculations or decisions that may then necessitate additional field tests.
| Field tests | ||||
|---|---|---|---|---|
| Test pits | Bore holes | Infiltration rate | Soil chemistry | |
| Remarks | Usually with a backhoe, includes inspection of existing NRCS reports, road cuts, etc. | Drilled or augered includes inspection of driller s logs for local wells, water table levels | Match the expected method of application, if possible | Includes review of NRCS survey |
