Here's an independently published study where the HydraSleeve was compared to using purge and pump sampling.
Concentration Comparison of Selected Constituents between Groundwater Samples Collected within the Missouri River Alluvial Aquifer using Purge and Pump and Grab-Sampling Methods, near the City of Independence, Missouri, 2013
This study includes agricultural nutrients sampled with the HydraSleeve as well as numerous other parameters. The takeaway is that HydraSleeves can work to replace the current sampling method (volume purging) except for sample volume needed for duplicates samples. The wells are all 2-inch diameter with 5-foot screen intervals, limiting sample volume available for no-purge sampling. The laboratory required 2-liters of sample for duplicate analysis. The investigators are planning to either reduce the number of parameters analyzed or reduce the analytical volume requirements for duplicate samples during the next phase of the study.
Please click the image to download the full report.