IDNR Laboratory Certification


IDNR Laboratory Certification

Underground Storage Tanks (UST)

With rule changes effective 2/11/2004, the IDNR groups the UST parameters into two analytical groups for the purpose of certification. In addition to meeting general certification criteria delineated in the UST laboratory certification manual, Underground Tank Program of the Iowa Department of Natural Resources, Criteria and Procedures, Quality Assurance, laboratories seeking certification must adhere to the following methodology.


Method OA-1: see OA-1 (in PDF) (December 2019)
Method OA-1 is used to determine the concentration of volatile petroleum hydrocarbons and other individual components such as Benzene, Toluene, Ethyl benzene, and Xylenes in water and soil/solids. It is a modification of EPA method 8015 and provides gas chromatographic conditions for the detection of certain volatile petroleum fractions such as gasoline. Samples are analyzed utilizing purge-and-trap sample concentration. Detection is achieved with a flame ionization detector (FID) alone or an FID with photoionization detector (PID) in series or mass spectrometer (MS). Identification of various petroleum products may also be performed by comparison of the chromatograms of samples and commercial products. Quantitation is based on detector response to an external standard of commercial product for this determination.

In addition to method OA-1, Method 8260 is also allowed.

Method OA-2: see OA-2 (in PDF) (Revision December 2019)
Method OA-2 is a modification of EPA method 8100 and determines mineral spirits, kerosene, diesel fuel, fuel oil, motor oil, and hydraulic fluid in a liquid or solid matrix. Laboratories must also run gasoline to be able to distinguish this product from heavier products. It covers the determination of low volatility petroleum products and organic compounds that are soluble in moderate to low polarity organic solvents and are amenable to gas chromatography. A flame ionization capillary gas chromatography method is used to quantitate the compounds or mixtures of interest. A gas chromatograph/mass spectrometer/data system may also be used. Identification of various petroleum products is performed by comparison of the chromatograms of samples and commercial products, preferably utilizing computer data system overlay. Commercial products are used as standards for quantitation.

NIOSH 1501 is an air method for soil vapor. PAH analysis by EPA method 8310 for water potential ingestion, EPA method 8260 for other.