Thanks for the reply. I am not too concerned about the material flow. These same manufacturer's produce Frac Sand bins with the same geometric shapes. The difference is the wall thickness.

The material properties for both products is defined quite well. I can understand the difficulty converting a grain silo to store Fly Ash. The flow of these material types would be very different, and I would image caking within the bin would be a primary problem.

The main concern with our numbers is being overly conservative. My client does own other sites, and has a basic understanding. That said, until about three weeks ago they did not seem to gather that the bins at their other sites have significantly thicker walls than those at this site. The bin I am concerned about happens to be the largest bins at the site and the most valuable for them. It is very difficult to explain why the material properties and bin geometry are reducing the storage capacity so much.

Our general plan to limit the fill level will be to install overflow pipes, an alarm system and possibly a PLC. That is if they purchase the site.

I do know about the risks when it comes to silos. I have looked into these before in a different capacity. I also grew up on a farm filling/emptying these things for years. I spent many a day inside wet bins cleaning them out and have watched grain almost stand up vertical in the fall when it came off the combine wet.

Brad ■

lz, they are quite set on considering the basic concept and to install a dome like structure will be problematic given the length of the existing rail spur and the fact this area has fairly heavy snowfall events. The idea of one storage facility makes a lot of sense to me. Grain facilities need many different bins to deal with all the different products and grades that arrive in the fall. These guys seem to have one good and multiple storage bins seems to be nothing but a nuisance.

We have spoken to the manufacturer of the material handling equipment. Their main concern was the durability of the equipment. Provided they dial down the flow rate, they anticipate that the system would function. This company manufactures both grain handling and sand equipment.

As I mentioned, we have no intent to completely fill the existing bins. Not only would that be a problem for the bins, but the foundations cannot support the increased loads. Do you know of any studies that discuss storing frac sand in a flat bottom bin? We asked them if they had any concern about compaction on many occasions, and they seem convinced this will be fine considering what they have found at there other site. I do not believe they currently own any flat bottom bins for sand storage. The largest storage capacity would be gained by re-using the flat bottom bins, so that would be a major problem if they cannot get the material to flow.

Thanks for your comments.

Brad ■