(Adds Shell comment on leak, details)
HOUSTON, March 1 (Reuters) - Royal Dutch Shell Plc's 316,600 barrel per day joint venture Deer Park, Texas,refinery was restarting a coking unit on Tuesday aftercompleting a six-week overhaul of several units, sourcesfamiliar with plant operations said.
There was also a leak in a line at the refinery on Tuesday,the sources said. No injuries were reported due to the leak.
A Shell spokesman declined on Tuesday to discuss specificunits at the Deer Park refinery.
"Shell Deer Park has experienced an upset in a processunit," said company spokesman Ray Fisher. "This incident isbeing handled within the boundaries of our facility and there isno impact to the surrounding community or to our industryneighbors."
The Deer Park Refinery is a 50-50 joint venture betweenShell and Mexico's national oil company Petroleos Mexicanos.
A coker increases the amount of refinable material obtainedfrom a barrel of oil and converts residual crude into petroleumcoke, a coal substitute. (Reporting by Erwin Seba; Editing by Sandra Maler)
