Louisiana Department of Environmental Quality Risk EvaluationCorrective Action

Louisiana Department of Environmental Quality Risk Evaluation/Corrective Action Program (RECAP)

Aquifer Tests

Appendix F n Current Use – 1 -mile radius water well survey – 500 -feet radius walking receptor survey n Potential Use – Maximum sustainable well yield » Direct Measurement » Estimated Measurement – Total Dissolved Solids (TDS) of groundwater » EPA Standard Method 160. 1

Figure 3 NOTE: CLASS 1 A - Currently supplies a public water supply. CLASS 2 A - Currently supplies a domestic, agricultural, or other supply.

Determine Site Constraints Soil Type n Thickness of Encountered Formations n Identification of Aquifers and Water Levels n Aquitards Encountered n Hydraulic Barriers n

Determine Aquifer Properties Hydraulic Conductivity (K) n Saturated Thickness (b) n Transmissivity (T) n Specific Yield (Sy) n Specific Storage (Ss) n Storativity (S) n Porosity (n) n

Unconfined Aquifer Unsaturated Zone Saturated Zone

Confined Aquifer Unsaturated Zone Confining Layer Saturated Zone Confining Layer

Direct Measurement of Aquifer Properties n PUMPING TESTS • Constant Rate • Step-drawdown n SLUG TESTS • Slug In • Slug Out

SLUG TESTS Slug In Unsaturated Zone Saturated Zone Water Flow

SLUG TESTS Slug Out Unsaturated Zone Saturated Zone Water Flow

Conceptual Pumping Test Models

Conceptual Slug Test Models

Estimation of Aquifer Properties HYDRAULIC CONDUCTIVITY • Published References • Laboratory Procedures • Field Procedures n AQUIFER THICKNESS • USGS, LGS, DNR, DOTD n SPECIFIC YIELD/SPECIFIC STORAGE • Published References n

Estimated Well Yield for Confined Aquifer

Estimated Well Yield for Unconfined Aquifer