Revert "using different dispersal method"

This reverts commit a09fe6a15224e6af53ac93b4b34e6627cb854097.
Revert "Revert "using different dispersal method""

This reverts commit 8ef415bd2cea393b11c2527ee18d85b242f54391.
Revert "jjv modifications to save memory usage, time and disk space"

This reverts commit e93e78bb04f52a4e65cdd247769f46988b76f5bc.