It’s done and it took twice as long and about $2K more than planned — even with NO rock base on arena. About three weeks before I was to start my project, I called another material yard to get another quote on the limestone rock. Imagine my suprise when they quoted me a price that was twice as much as my local dirt yard, but almost the same price per ton. ??? When I called them, they admitted they weren’t REALLY sure how much a yard of limestone weighed – which is pretty critical to be able to convert the amount of material needed to tons for pricing purposes. That put a huge kink in my project, since it added $5,000 to the final price. And that was just more than I could do. So, to plan B. I had found a limestone ‘substitute’ called calcium sulfite. It is marketed by DuPont and is used in many applications where limestone might be used – huge railyards, chemical plants, etc. But it weighs half as much as limestone, thus making it much cheaper to truck since they can deliver more volume per truck. And it packs like limestone, but requires water to set up. My major concern was that it seemed this material ‘bonds’ and sets much like concrete – since according to the specs, you have about 3 hours to get it spread/compacted once you water it, before it sets. The salesman said they had sold it to some people for arenas, but could not give me any references so I was leery about spending $5K on an ‘experiment.’So I decided to comprimise. I built a new,70-foot round pen, and put the rock base in it so that hopefully I would have one ‘foolproof’ weatherproof place to ride, and just fix the clay base on my existing arena. I rented a 500-gallon water trailer and an 11-ton compacting vibrating roller for the project. I thought I would need about 10 loads of fill to build the round pen base and bring the sides up on my existing ring and fix the areas in the middle that had settled. I ended up needing 23 loads of fill. I built the new 70-foot round pen at the far end of my arena. It has a 6” clay base with 4” calcium sulfate on top of that, and 2″ of sharp sand as the footing. The calcium did not pack as well as I hoped – I used the vibrating roller and put 1,000 gallons of water on it to get it to ‘dough’ consistency per their specs. I rolled it for about 5 hours. Well, it’s probably packed, but still has loose rocks on top which about 1/3 are of a size to be a concern. I’ll be picking rocks for awhile and will be very interested to see what happens when it rains the first time. The dozer guy I used was super and got the arena base crowned perfectly with a 2” drop from center to rail on both sides. Arena LOOKS beautiful, can find no low spots walking around on it, but clay base also did not pack as well as both dozer guy and I both had hoped – but it was a bit wet, so gave it some time to dry out before riding on it. The dozer did not make deep ruts in it but sand truck – the big one with 12 yards anyway – made huge ruts. I was really hacked at the sand yard – they said they could deliver all the sand in one day. They couldn’t – which cost me another day of dozer work. One of the many dumptrucks took out my new 14’ gate and knocked the brand new gate post out of line. One of the sand trucks drove on the calcium round pen base before it was cured – despite me jumping up and down and waving him away – leaving huge ruts – and then instead of just backing up, he TURNED AROUND on it. So we had to repack that
and hope it’s ok. I spent a total 12 hours driving the 11-ton vibrating roller back and forth over two days and was a freaking tired, nervous wreck about the mounting ‘over budget’ items. But if it works out it will be worth it all. Now I have to find some railroad ties to line it, and find someone to deliver them. I need 54 of them and they weigh 100 lbs each. I’d have to make multiple trips and will gladly pay someone to deliver them. I figure I can move them with my tractor. If I had to do this again, I would bring in dirt, have shaped and then just let it sit about 6 months – over a winter for sure. Then come back and fill in settled spots, etc. I also would get dirt samples from different pits to test ‘compression’ or whatever they measure to see which packed/hardened best. My original base was made from material from my pond and that packed GREAT. If I had realized I would need as much fill as I did – I would have had dozer guy just take more material from my pond. Now I need to get water faucets out there so I can water it. But at least that’s a cheap project. Trencher is $175 a day plus muscle – now’s the right time of year to be doing heavy lifting, for sure! The sand is an angular sand with small pebbles in it – called ‘sharp’ sand down here. It is wonderful stuff but is very expensive – in fact, the single most expensive part of the arena. I have ridden on it twice. I am most concerned about a specific area where both Fling and Faxx ‘punched through’ the sand and into the base, which was still quite soft. It is on one side, where we had to add the most fill to bring the sides up to a 1% grade. The new base is probably 12″ deep in that spot. I am HOPING it is just because the base sitll has not dried. In retrospect, I would have let the base sit with no sand on it a few days to dry. Otherwise, it’s breathtakingly wonderful — only about a 10 foot circle at one end where the sand is a bit too deep, but that’s incredibly minor. I can feel no low or sloping spots riding on it. Other than the nagging soft base worry, it is by far the best arena I’ve ever built.
If the base continues to be soft, I’ll call dozer guy and see what he suggests. One ‘cheaper’ fix would be to carefully scrape sand off that area and spread some lime or portland cement and carefully disc into the top 1-2″ of base, then re-pack. My former arena had portland cement worked into it, and it was very hard. But I’m really hoping I don’t have to do that. I haven’t ridden in the round pen yet – we very cleverly put up the hot wire fencing with no ‘gate’ to open it, so need to fix that before I can even get into it. LOL!
Below, you’ll see a “before” and “after” picture of the arena.