There is a zombie thread re the above statement ( Split pea soup too crunchy ) that offers up many different tips to correct the problem but I wanted more....
We had a deer camp in NW Texas for many years and for some reason I could never get the huge vats of pintos (those boys loved their beans lol ;-) to soften despite the many different tips and trix I applied.
Ended up just preparing at home and transporting them (the beans not the boys lol) in a cooler packed with crushed ice.
Been awhile since we hunted that ranch but the revival of the above mentioned thread made the scientist in me itch and so I took a google journey to try to satisfy my curiosity (as well as maybe verify my own theory).
Knowing the info on the WWW is not always reliable I tried to stick with the more scientific sites to verify my long held suspicion that at least one reason was the mineral content of the water.
I pulled up a geology map re the mineral content of the area we hunted and found it to be "hard" (extremely high in calcium) and that led me to a couple of other charts and studies and the conclusion that yes...water with a high calcium content is less than optimal when trying to cook dried peas/beans (PM me if you want to look at my research and I will gladly cite if you want to fact check).
A much easier read below.... (I know that the never pre salt dried beans contingent will be heard from so a pre-emptive message from me.... plz don't shoot the messenger...ignore what I dug up and continue to use your bean cooking process...I always pre season mine with lots of salt as well as other spices and have never had a problem other than at that ranch in NW Texas).
In other words I am claiming my right of IMO.... .
"In recent testing, we’ve found that soaking dried beans in mineral-rich; hard tap water can toughen their skins. Some recipes recommend using distilled water to avoid this issue, but we’ve discovered a simpler solution: adding salt to the tap water, which prevents the magnesium and calcium in the water from binding to the cell walls, and it will also displace some of the minerals that occur naturally in the skins. We found that three tablespoons of salt per gallon of soaking water is enough to guarantee soft skins." (excerpt from C Kimble's blog at America's Test Kitchen)
IDK if this is why @Deedesroc123 (current OP of the pea soup thread) is having so much trouble but I suspect it may be (it certainly puts my questions to bed) and a simple fix would be to use bottled water as I am not too thrilled with the idea of pretreating tap water with a bunch of salt.
Reason being: I don't know if I would want to ingest ANY liquid that high in calcium...unless I was wanting to pass a huge kidney stone lol.
To quote @IceMan...
I'm not sayin'...I'm just sayin'.