Go to a ped where you experienced the sparking. Use your 188 B voltage tester or new style voltage tester, if thats what your company uses now, and check for a hot box or ped. If hot walk away and report it. If not, break the bond in and out and using a vom or sidekick or craft interface unit, check all bonds to earth ground and crossbox or ped to ground in and out. All test points should be 4 or 5 ohms or less to ground.
Example: If you check ten points to ground and get 4, 5, 9, 2, 3, 7, 2, 1, 3, 15 ohms I would look at the 9,7 and 15 sections for grounding or bonding issues.
