Pumps for 2-Inch Monitoring Wells: Sampling vs. Well Development
For low-flow sampling in a 2-inch monitoring well, the Royal Eijkelkamp MP 1/Redi-Flo2 is the standard for deep wells (up to 275 ft total dynamic head), 12V Proactive pumps suit shallow wells (about 200 ft or less), and bladder or double-valve pumps are the pick when VOC retention matters. Sampling pumps are not well development pumps: the MP 1/Redi-Flo2 is specifically not for developing a well, so call us before using any sampling pump for development.
Sampling vs. well development: two different jobs
Sampling (and purging) pulls a representative groundwater sample at a low, controlled flow rate with as little disturbance as possible. Well development comes earlier: after a monitoring well is installed, it is typically developed to remove fine sediment and drilling disturbance so water flows freely from the formation. The two jobs need different equipment and different flow rates.
Manufacturer limits matter here. The MP 1/Redi-Flo2 product page states the pump is not for use to develop a well, and the Proactive Mega-Monsoon is not engineered to sit in the water 24 hours a day. If your project requires development, tell us your well diameter, depth and regulatory requirements and we’ll recommend the right equipment. Contact our team.
Sampling pump options for 2-inch wells
| Pump | Best for | Key specs | EE+S rental (day / week / month) |
| MP 1/Redi-Flo2 | Deep wells where sample integrity is critical | Up to 275 ft total dynamic head; variable frequency drive (25–400 Hz) sets the flow rate; stainless steel; VFD controller rented separately; not suitable for PFOA/PFOS sampling; not for developing a well | $100 / $450 / $1,575 |
| Proactive Mega-Monsoon (12V) | Shallow wells, continuous purging and sampling | Pumps up to 200 ft from ground level; runs on a 12V deep-cycle battery through a Low Flow with Power Booster 3 controller; 1.82 in diameter x 26 in; 400-hour motor life | $115 / $520 / $1,810 |
| Proactive Monsoon, SS Monsoon Pro and SS Hurricane Pro | Routine 12V monitoring events; stainless steel options ease decontamination | Fit standard 2-inch wells; compatible with low-flow controllers; fast setup | $100 to $1,575 (day to month, by model) |
| QED Sample Pro bladder pump | VOC samples and strict low-flow protocols | Air-driven; no air-to-water contact; low-flow control (down to about 100 mL/min with the right controller); field-serviceable bladder; needs two lines, a controller and an air source | Poly: 50–790; Teflon®: 70–1,100 |
| Solinst Model 408 Double Valve Pump | VOC protection with higher pumping rates; wells with solids | 316 stainless steel; 1.66 in x 2 ft; no bladder to replace; survives dry pumping, dirty air and sand; tool-free decontamination; needs two lines | $50 / $225 / $790 |
| Peristaltic pumps (Alexis, Masterflex E/S) | Shallow water levels and low-flow sampling | Surface-mounted, so the sample touches only the tubing. See our peristaltic pump guide | 35–550 (day to month) |
Rental rates are the current envisupply.com rates. A prep fee or freight may apply to some items. 12V pumps from Proactive are described by the manufacturer as PFAS-free; confirm for your project.
What you need besides the pump
- MP 1/Redi-Flo2: the VFD controller is required and rented separately; a pump shroud (included in the rental) is needed in wells larger than 3 inches.
- 12V pumps: a compatible low-flow controller and a 12V deep-cycle battery.
- Bladder and double-valve pumps: a controller and compressor (for example, the QED MP10 controller, the QED 3020 compressor, or a Solinst controller), plus two lines down the well.
- Tubing: bladder and double-valve pumps run on bonded dual tubing. See our sample tubing comparison and the guide to which tubing to use.
- Filtered samples: pair your tubing with an in-line filter. See our in-line groundwater filter comparison.
Rent or buy?
For quarterly or semiannual monitoring events, renting keeps equipment current, calibrated and off your books. Buying starts to make sense when you sample many wells on a frequent schedule. Current purchase prices include the Proactive Cyclone 12V plastic pump at $105, the Proactive Hurricane 12V plastic pump at $600, the Proactive Low Flow Sampling Controller at $500 and the MP 1/Redi-Flo2 VFD controller at $2,650. Browse rental pumps or pumps for sale.
Frequently asked questions
What is the best pump for sampling a 2-inch monitoring well?
It depends on depth and data quality needs. For deep wells, the MP 1/Redi-Flo2 handles up to 275 ft of total dynamic head. For wells about 200 ft or shallower, a 12V Proactive pump is faster to set up and more economical. For VOC samples, a bladder or double-valve pump limits air contact and preserves volatiles. Always follow your site sampling plan and regulatory guidance.
Can I use a groundwater sampling pump for well development?
Not necessarily. The MP 1/Redi-Flo2 is specifically not for use to develop a well, and the Mega-Monsoon is not designed to be left in the water around the clock. Development typically calls for different equipment and higher flow, and requirements vary by regulator and well construction. Contact us with your well details and we’ll recommend the right equipment.
Which pump is best for VOC sampling in a 2-inch well?
Bladder pumps and double-valve pumps are the usual choice because the water is pushed to the surface without contact with the drive air, which helps retain volatile compounds. The Solinst Model 408 also offers higher pumping rates and tolerates solids. Check the regulations for your site, as some programs specify the pump type.
Not sure which pump fits your project?
Our team can recommend equipment based on your well construction, sampling depth and regulatory needs, and we keep a full inventory of rental and purchase options ready to ship. Browse rental pumps, contact us or call 717.901.8891.