Get seal piece at dig was a mission in Jak II. Young Samos Hagai and Onin had found out a Seal piece of the Seal of Mar was contained within the ancient carvings of the lurker totem at the dig site, they sent Jak to go and find it.
The PlayStation 3 and Vita versions of this mission are related to a trophy named "Clap Hands", completing this mission will reward you with a silver trophy.
The dig site changed a lot since you destroyed the drill last time. No more Krimzon Guard this time but a pair of large open caverns with a big number of scaffolding and platforms occupied by Metal Heads (some manic heads, sling blasters and a huge amount of stingers). The moment you arrive at the dig site you will be greeted by a large number of stingers, who burrow out of the ground. They will do this a lot whenever you are at ground level, so take care to watch your step.
Moving out into the main area you will notice some a walkway in front of you, a large lurker village situated on the walls and a barrier running down the middle of the area, effectively forcing you to take the long way around into another cavern you can access (two routes, using the walkways or on the ground level through a passage past the gap on the right) and to reach the village you will need to press five buttons hidden throughout the dig site.
To start with, go along the scaffolding and take the grind rail here into a tunnel. Ignore the new cavern on your right for a second because further ahead is the first button. Now go back to the cavern and take a right (there will be several of these turning spiked log traps); you can see a Precursor orb floating over some metal constructions.
The idea here is to dive punch and lower each metal cube; but too much and it will fall out causing the entire row to collapse. Just do it the safe way and press them one by one; from left to right and back again until you can get to the button in the room below.
This room is linked between the big two caverns we just went through but leads to the bottom level; where the ground is infested with stingers. A little forwards is the third button, now climb back onto the walkways to avoid the constantly re-spawning stingers. There's a lone sling blaster in the center of this room guarding the fourth button. From here on; turn around take a left going past the metal cube puzzle and towards two manic heads and another sling blaster.
After killing these enemies climb up the platforms they were guarding and take the grind rail to the next structure; nearby this one down on the ground is a door and a patch of open sand. Jump down here and you will be harassed by an unlimited amount of stingers again. Quickly go through the door and press the last button, then get back to the scaffolding you just jumped down from.
Now you will have to grab the trapeze hanging from the balloon which is operated by a babak and flying back and forth. Use it to reach the next area (with the big log) where you are be greeted by numerous stingers again. Climb up here past the manic heads and head into the tunnel where more stingers await you. Go over the lava by using the rocks (they will sink) to find another two trapezes swinging back and forth.
Now you are back in the first cavern; specifically the one where the drill was. You will have to get over the half-log trap and use two wheels with two platforms each to get a little higher. be warned though as there's another sling blaster attacking you at the second one. The last obstacle is a device which dumps a spiked metal ball onto the walkway as well as one into the gap next to it; this one purely relies on your timing so just run past it when one ball has dropped.