As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF AT FL 070, COULD NOT REINSTATE AIR CONDITIONING PACK. AIRCRAFT WOULD NOT MAINTAIN PRESSURE WITH ONE PACK OPERATION. JETTISONED 8000 POUNDS OF FUEL AND RETURNED TO RNO WITHOUT FURTHER INCIDENT. MAINTENANCE REPLACED THE RIGHT PACK SHUT-OFF VALVE. OPERATIONAL CHECK WAS NORMAL.