The 25-year-old has been told that he is surplus to requirements at Oakwell under new manger Paul Hart (pictured) and he is free to find a new club.
Hartlepool have now agreed to take Lumsdon on during pre-season, where he will hope to a earn a move to Victoria Park.
Lumsdon moved to Barnsley in December 2001 after a successful loan spell from Sunderland, and made nearly 100 first team appearances for the South Yorkshire club.
