Hazardous Waste Program fact sheet
Division of Environmental Quality Director: Leanne Tippett Mosby

This fact sheet is intended for use by participants in the Brownfields/Voluntary Cleanup Program. The following soil and groundwater sampling procedures are not intended to serve as a comprehensive standard operating procedure, but rather a list of guidelines to address common sample collection errors.

Soil Sampling

For further information, please refer to the department’s fact sheet MO Risk-Based Corrective Action for Petroleum Storage Tank Sites Preservation of Samples Analyzed for Volatile Organic Compounds online at

Groundwater Sampling

Refer to the following for references for further information:

  • EPA Low Flow Groundwater Sampling Procedures
  • ITRC Diffusion/Passive Sampler Documents

    • Bailers/Pumps
      Current research indicates bailers are not the best available technology to collect groundwater samples. Studies have demonstrated that levels of volatile organic compounds in samples obtained with bailers are statistically lower than in samples obtained with other devices. In addition, bailing can cause increased turbidity.

      The use of inertial lift pumps (e.g., Waterra, hand pumps) for sample collection is not recommended because they create a surging action, which may cause increased turbidity, loss of volatiles, aeration and degassing of samples.

      Peristaltic pumps should be used with caution, as the vacuum created may cause volatilization and degassing in gas-sensitive or volatile samples.

      Sample tubing should be selected carefully, as some flexible sample tubing (e.g., silicone and tygon) may leach plasticizers or adsorb or desorb organic compounds.

      Bailers and peristaltic pumps are acceptable only in certain situations, such as grab samples from temporary wells and only with prior approval from the Brownfields/ Voluntary Cleanup Program. When these methods are used, sampling personnel need to be properly trained since sampling results are highly dependent on the skill, care and consistency of the person collecting the samples. With bailers, great care must be taken to slowly and gently lower and raise the bailer in and out of the water column, and, when samples are to be analyzed for volatile organic compounds, a bottom emptying device must be used to decant samples to their respective volatile organic compound vials. With peristaltic pumps, a low flow rate (0.1 to 0.5 liters per minute) must be used to minimize volatilization. Research has shown that low lifts, low pumping rates and using non-sorptive tubing such as Teflon minimize the negative effects these pumps can have on a sample.

For More Information
Missouri Department of Natural Resources
Hazardous Waste Program
P.O. Box 176
Jefferson City, MO 65102-0176
800-361-4827 or 573-526-8913
573-526-4817 fax