Even if you need to use cartridges, getting the water out will make your loading easier and surer. The chances of cartridge separation will be lessened when you don't have to drop them into or push them thru the water. If you don't try to dewater, just a few feet of water will come right up the hole as it's displaced be each cartridge. so if you've got 5 feet of water, you're going to need close to 15 feet of cartridges to dry up the hole.
If you originally intended to load with ANFO, your best bet is to dewater and use WR-ANFO in that portion of the hole that was wet. Dewatering and using regular ANFO is a risky business. That product is almost instantly soluble and when affected by moisture, most likely will produce a low order detonation at best. WR forms a water resistant gel coating where it touches the part of the borehole that was wet. Dewatering and using WR will give you the identical powder factor that you intended when you established your drill hole spacing and burden.
This website will describe the pneumatic displacement pump designed specifically to dewater small to medium diameter drill holes. The pump will easily lift water from more than 100 feet with the air delivered by a small compressor of about 20 CFM at 100 PSI or so.
4 minute dewatering video
Blasthole Dewatering
Simple borehole dewatering with air pressure
Contact us to discuss your situation or to place an order.
When water shows up unexpectedly in your drill holes, you have to make some compromises. If you have access to repump emulsion you can evaluate your ground and judge if that is an appropriate solution for your conditions. If that product isn't an option, you can consider cartridges of various water resistant products and load into the water.
The down side to that choice is considerable additional expense and less than optimum blast results. Your shot won't be as good because your powder factor using cartridges will be significantly less that what you calculated for your drill pattern and hole size.
E-mail: 7pkunze@itstriangle.com Ph: 406-654-1727
BDS Inc Box 1160 Malta, MT 59538 USA