Changes in soil chemical characteristics due to wastewater application by subsurface drip systems were
investigated at four sites in Texas. Soil samples were collected from different locations and depths around drip emitters and
from outside the drip fields. These soil samples were analyzed for phosphorus (P), total nitrogen (TN), sodium (Na), calcium
(Ca), magnesium (Mg), soluble sulfate (SO4), potassium (K), salt content (EC), and total organic carbon (TOC). Application
of wastewater resulted in a significant increase in soil Na where concentration of Na in the applied effluent was high and Na
concentration in the original soil was low. Concentration of P was significantly increased in the vicinity of the emitter and
near the soil surface where the drip line was installed at a shallow depth. There were no drastic changes in TN, Ca, Mg, K,
and TOC concentration or in EC values in the soil profile.