Hmm, you want general tips?

1. Don't use yourself as a character.

2. Why are the miners rebelling?
The explanation of this is one sentence saying "They were rebelling." Why? There isn't any pathos associated with a statement of fact like that. Hell, write an entire chapter about what set in motion the rebellion, cause it seems fairly important.

3. Watch tense and agreement.

The elevator clangs to a stop, and Puffie searched the corridor beyond with the flashlight on his blaster.

This sentence changes to present tense, then back to past tense. Just an example.

No one was there except for a group of 5 rabbits at a table.

It's certainly not empty then, is it? So why insinuate that it was? This sentence contradicts itself.

The mine was silent again, except for the slow dripping of water somewhere up ahead.

Same thing here.

4. Don't caps a sentence.

"(-)! WE GOT A NEST OF 'EM!"

Talking in caps makes your writing less mature. Try using words with loaded connotations.

5. Don't capitalize non Proper nouns.

6. Type out numbers. Compare 20 to twenty.

7. Avoid repeating words unless it's to convery something big like theme.

Amber beams of light sizzled their way to the chest of a rebel, who clutched his chest.

In general, a lot of knowledge is assumed, which leads to confusion. What are Terminators? Everything you say needs an explanation, which is a great opprotunity to add details to your story and basically enrich it, so long as it dosen't start to drag everything down.