Quake II/Toxic Waste Dump

Level objective
The objective for this level is to fight your way to the entrance to Pumping Station 1 and go through it. After completing that level and also Pumping Station 2, you will return to this level and your objective then is to fight you way to the exit that takes you back to The Reactor.

Secrets
This level has two (2) secrets. Both require you to swim in toxic waste. You can use an environment suit or an invulnerability to avoid damage or you can tough it out and lose a lot of armor and health. Here is where the secrets are and how to get to them:
 * 1) When you first come out into an open area, look up.  You will see a sloping structure and, above that, a horizontal structure.  The sloping structure is a channel containing toxic waste.  If you slide down that and continue a short way, you will get to this secret.  You will then need to come back out the way you went in, still in the toxic waste, and hop up onto the edge of the channel.  From there, you will be able to make your way around a ledge on the wall and carefully drop back down without any damage.  After making some more progress through the level, you will come out on the upper horizontal structure, which is a walkway.  You can drop down onto the edge of the toxic waste channel from the far end of the walkway, walk down the edge as far as you can and then plunge in.  Otherwise, continue the level and you will find an environment suit at the border of a pool of toxic waste.  From that point, jump in and turn around.  Go back under the path you took to get to there, turn right at the end and go down the channel to the secret.  If you activated the suit, you should be able to get the secret stuff and make it back out before the suit runs out.  There is a replacement suit in the secret room.
 * 2) You can get to the second secret from the pool above which you found the environment suit.  Jump in, dive and zigzag to the right and forward twice.  However, if you then turn around and swim back to try for the first secret using a single suit, it will run out before you can get out of the toxic waste.  An alternative is to wait until you come back to this level after completing the Pumping Stations.  You arrive back at an open area that you've not seen before.  There are narrow ramps into the toxic waste below and you can use these to get back out if you go for this secret on its own.  From the steps down which you return to this level, make a hard U-turn to the right and get up on the raised edge of the platform.  Walk to the corner, facing the wall.  The opening that leads out of this area and back to the part of the level you've already visited will be to your left.  Jump forward into the toxic waste, activating the environment suit in mid-air, and dive down to the secret.  To get to the first secret as well using only a single environment suit, swim up, zigzagging twice to the right and forward.  Surface and run along the channel, turning right at the end to go down the slope to the secret room.  You should have time to grab the secret stuff and get back out before the suit runs out.  Note that if you take this route as soon as you get back from the Pumping Stations, you will have bypassed part of the level and won't be able to get to the button that operates the bridge over an area of toxic waste.  Therefore, to get all the kills, you should go at least as far as that button and then come back to dive in for the secrets.