find all .svn folders:
find . -type d -name .svn
./.svn
./sourceA/.svn
./sourceB/.svn
./sourceB/module/.svn
./sourceC/.svn
delete all .svn folders:
rm -rf `find . -type d -name .svn`
via: http://www.anyexample.com/linux_bsd/bash/recursively_delete__svn_directories.xml