Snap Sampler - Representative Results for Passive Samplers

Performance Objective	Data Requirements	Success Criteria	Results
Quantitative
1. Ability to sample a range of contaminants at site	Adequate sample volume for all analyses	Similar detection capabilities (as with low- flow sampling)	Yes
2. Reproducible data	Analyte data for replicate samples	Among replicate samples, a %RSD of 25% or less, or equal to or better than that for low-flow samples	Yes for VOCs, dissolved inorganics, and total non- metal ions. Testing problems occurred for some total metals analyses for both Snap Sampler and low-flow sampling
3. Agreement between sampling methods for analytes of interest	Analyte concentrations for each sampling method for all wells	Lack of statistically significant differences Lack of bias	Yes, except total Fe and total Mn, where testing problems limited determinations
4. Reduced sampling time	Field records of activities at each well	Less time needed to sample a well	Yes
5. Less costly sampling method	Records of the costs for equipment and supplies Field record of technician’s time	Cost savings of at least 25%	Yes, 46%-67% cost savings
Qualitative
1. Ease of use	Field records of activities at each well	Technician able to learn the procedure with relative ease	Yes
2. Ease of use	Field records of activities at each well	Few problems requiring second attempt to sample the well	Yes (providing manufacturer’s directions were followed)
3. Ease of use	Feedback from field technician	Operator acceptance	Yes