U.S. EPA Contaminated Site Cleanup Information (CLU-IN)


U.S. Environmental Protection Agency
U.S. EPA Technology Innovation and Field Services Division

Dense Nonaqueous Phase Liquids (DNAPLs)

Detection and Site Characterization

Halogenated Alkanes

1,1-Dichloroethane

1,1-Dichloroethane(1,1-DCA) is a volatile halogenated organic compound and as such is subject to most standard characterization and analytical techniques used on this class of chemicals. Methods such as vertical profiling, dyes, and standard GC/MS are discussed in the main section for DNAPLs detection and site characterization.

Diffusion Samplers

1,1-DCA contaminated groundwater can be sampled by Diffusion Samplers (ITRC 2004).

Laboratory Methods

Analysis of 1,1-DCA can be performed using standard analyses such as SW-846 methods 8021bAdobe PDF Logo, 8260bAdobe PDF Logo, and 8260cAdobe PDF Logo.

Field Screening Methods

1,1-DCA should be detectable using headspace analysis with a field GC. Standards should be run to verify detection limit requirements. If the GC uses a photoionization detector (PID) instead of an electron capture detector (ECD) the lamp must be 11.7 eV as the standard 10.6 eV lamp will not ionize 1,1-DCA, which has an ionization potential of 11.06 (HNU 1997). This requirement would also be true for an organic vapor analyzer using a PID.

GasTec makes a detection tube that will detect 1,1-DCA in the 7-70 ppm range. It is not specific to 1,1-DCA and is subject to interferences from other chemicals (e.g., chlorine, bromine, iodine, chloroform, dichloromethane, methyl bromide, trichloroethane, trichloroethene, and tetrachloroethene).

References

Photoionization Characteristics of Selected CompoundsAdobe PDF Logo
HNU Systems, Inc., 12 pp, 1997

Technical and Regulatory Guidance for Using Polyethylene Diffusion Bag Samplers to Monitor Volatile Organic Compounds in Groundwater Adobe PDF Logo
Interstate Technology & Regulatory Council (ITRC), DSP-3, 78 pp, 2004

Test Methods for Evaluating Solid Waste, Physical/Chemical Methods
U.S. EPA, SW-846 on line