Hal Owen & Associates Inc., PO Box 400, Lillington, NC 27546
SOIL INVESTIGATIONS
A soil scientist uses hand auger borings or excavated pits to observe the soil profile. He uses information about landscape position, drainage patterns, vegetative cover, and local geology to predict changing soil patterns. Then, using an aerial photograph or a survey map with known points, he maps the dominant soil units that he observed on the investigated site.
The intensity of a soil investigation will vary depending on the amount of information you require. We will provide a report describing our findings and a map demonstrating the soil units observed. Please note that virtually no investigation, no matter how exhaustive, can identify all conditions below ground and inclusions of contrasting soil may occur within a mapped soil unit.
Soil Investigation for On-site Septic Systems (perk test)
We’ve come a long way from the old “perk test” where water was poured into an open hole to see how fast it was absorbed. Today, Soil Scientists observe soil morphology (texture, structure, clay mineralogy, organics) and other physical properties that are independent of the weather to determine the suitability of the soil to support sewage treatment and disposal systems. Using sound science, we can determine the ability of the soil to support various system types from conventional gravel drainlines to highly engineered pretreatment systems to surface application systems. In addition, we can provide recommendations about lot sizes based on septic demands.
Flood Hazard Soil Investigation
Activities within flood prone areas are often regulated by local or county ordinances. While GIS and Soil Surveys can be beneficial in identifying potential flood hazard areas, on-site verification and delineation are often necessary to meet regulatory requirements. Our Licensed Soil Scientist can identify flood hazard soils and delineate the boundary, and prepare a report needed to meet these requirements.
Soil Investigation for Stormwater Management
Designers of stormwater control measures (SCM) often need to know the specific, on site soil characteristics where the proposed device will be installed. A soil investigation can provide the necessary data for your project, such as the depth to the seasonal high water table (SHWT) and estimated permeability of various soil layers. We can also conduct hydraulic conductivity tests which provide an in-situ measurement of water movement through the soil, as required by the NC Stormwater Design Manual for certain SCMs.