From the level start, head south into the blood-floored area. Go through the opening on the right, go up the stairs, and run across the gap to get the rocket launcher. Ahead of you is a bridge crossing another bloody pit. On the other side is a blood-splattered wood-panel wall in the corner. Open this wall to reveal a secret teleporter that takes you to an otherwise unreachable area.
From the ledge you were taken to in secret #1, you can see a metal "well" just below in the blood pool. Drop into it to get the soul sphere inside.
Return to the bridge from secret #1. This time, drop off the west side. You can lower the bloodfalls here like a lift, which will reveal another teleporter to a secret area.
From the exit, it is possible to jump between the burning barrels into the well (secret #2) before raising the bottom. As the only way to raise it is to jump into it from the west ledge (the east walls are type 119 [W1, UP, Next Neighbor Floor]), you will become trapped.