the problem is determining exactly where the sediment is coming from. It could be a zone in the rock,or a well casing problem. If its a zone in the rock and your pump is below that zone,pulling the pump above it,most of the time will solve the problem. If its a casing problem,its usualy at a depth that is inaccessible and has to be resolved by installing a jaswell seal. A jaswell seal is a fitting on the end of 4" PVC pipe that when inserted,it blocks anything from getting down the hole of the well. Its basicly a pipe in a pipe. It gets inserted a good 10 to 15 feet past where the casing is in the well. You could also get point of entry filtration to remove the sediment. There are sand seperating untis out there. There are well companies that do well inspections using down hole cameras. Alot of times they can pin point where the sediment is coming from.