The Reston Chlorofluorocarbon Laboratory

Surface Water Sampling

Why Sample Surface Waters for CFCs?

Locating the source of contamination of ground water

During the Oklahoma study, (Busenberg and Plummer, 1992) sewage returns were found to be the major source of CFC contamination.

Determining processes occurring in streams

The Oklahoma study (Busenberg and Plummer, 1992) revealed a gas exchange between the stream and the atmosphere, and a discharge of old ground water into the stream.

Recharge of ground water by surface waters

The technique demonstrated the recharge of an aquifer by a contaminated stream in Oklahoma.

Identification of flood events

Processes associated with flooding include contamination with CFCs, very high concentrations of nitrogen and argon, suggesting very rapid recharge of the aquifer during flooding in Arizona (Glynn, Busenberg, and Brown) and the recharge of an aquifer through a sink hole in Georgia.

Study contamination history of a river

The Danube River recharges the Little Hungarian Plain Aquifer. The ground water has preserved the history of the contamination of the Danube River. (Bohlke, Revesz, Busenberg, Deak, and Deseo)

Sampling Surface Waters Methods

Syringe Method

Syringe

Dip and Fill Method

Dip and Fill

1. Fill ampoule as shown. Empty at least once

2. Empty neck of ampoule and seal

Use of Pumps to Sample Surface Waters

Pump

1. The best procedure to sample surface waters is to place the Bennett pump in the stream or spring. Six inches of water is required. The procedure is the same as that used for ground-water samples.

Pump

2. You can use the Bennett to sample 1/2" wells and surface waters. Your Bennett manual describes the procedure. You will need a fitting to connect 1/4" tubing to the pump. The Swedgelock part number is B-400-1-2 (brass) and SS-400-1-2 (stainless steel). Place a screen in the intake to prevent sand from damaging your pump.