1.  Equivalent analyte detection limitis

Detection levels for all AGI and low-flow samples.

Detection levels near or below EPA’s MCL values for all contaminants tested.

APG site: The MDL for AGI sampler was below the MCLs. However, it was ~20x > low-flow MCL.   

Pease site: For most analytes, MDLs equivalent to low-flow.

MDLs were 10x <&nbsp; MCLs.

2.&nbsp; Equivalent analyte concentrations to low-flow sampling

Analyte concentrations for each sampling method for all wells

Lack of statistically significant differences at p <0.05

APG site: Significant differences for several analytes.

Pease site: Generally no significant differences; poorest agreement for benzene and xylenes

3.&nbsp; Comparable concentrations across the entire range of analyte concentrations present

Analyte concentrations for each sampling method for all wells

Linear least fit model shows linear relationship with a slope that is not significantly different from 1.0

Both sites: Significant linear relationships between the AGI and low-flow data, with a slope = 1.0, for all analytes except TCA and CF at APG and toluene at Pease.

4.&nbsp; Ability to measure vertical profiles within wells

AGI results from all depth intervals tested.

Vertical profile of wells with AGI Sampler

Vertical profiles revealed.

Pronounced concentration gradients in wells near plume epicenters, even in a well with a 5 ft screen.

5.&nbsp; Cost savings

Records of the costs for equipment and supplies

Field record of field crew’s time

Cost savings of at least 25%

APG site:&nbsp; Cost savings of 18% to 35%, depending upon the size of field crew.

Pease site: Cost savings of 10% to 25%, depending on size of field crew.

Both sites: Cost savings of 30% to 40% using recent price quote for samplers.