The repository address is:
svn+ssh://atlas1.hep.anl.gov/users/svn/hpc/
Run the following on your command line:
svn co svn+ssh://<username>@atlas1.hep.anl.gov/usrs/svn/hpc <optional-local-directory-name>
This will check out everything in the repository to the directory hpc
or if the 'optional local directory name' is given, it will be located in that directory.