Low Flow Water Quality Sampling | YSI 556

Since the 1995 USEPA publication of the document "Low-Flow (Minimal Drawdown) Ground-Water Sampling Procedures" (EPA/540/S-95/54), low-flow sampling has increasingly been used over traditional groundwater sampling methods, such as bailers or high-speed pumps. Many government agencies encourage the use of low-flow sampling as it is designed to collect a sample that most accurately represents water from the screened section of the aquifer surrounding the monitoring well. Water is pumped out of the well with a variable-rate pump, and a sample can be collected after water level and field parameters stabilize over three consecutive readings taken three to five minutes apart. Overall, low flow sampling reduces physical and chemical stresses on the aquifer, reduces the variability in sampling procedures, and reduces the chance that changes in chemical concentrations are induced by the sampling technique.

The YSI 556 with flow cell is a perfect tool for low flow sampling. The compact, easy-to-use instrument simplifies field sampling, and water quality parameters can be continuously monitored and recorded to determine well stabilization. For more information, contact Fondriest Environmental at 888-426-2151.