Dystopian piece

Hey, I noticed that you didn't have any reviews for your piece, so here I am!

Let's get started.

It is so dark; like an event horizon where nothing could be seen for miles. No light was present. The unbearable smell of toxins; it is so awful it is like having a fire started up your nostrils. The unbelievable pain; shooting up my legs from running so long. There is truly no hope left. I am running blind; no idea where I am, how far I’ve gone. I just have to keep going, I can’t stop. I can never stop.

This is a great opening! However, you need to clear up the first sentence because as it stands, it doesn't make much sense. The word "event" I think has been misued here. After this it just needs some tightening up so that it reads a bit more smoothly

As the bright shimmering sun shone through the dull opening of the cave;

Neither of these words are bad on their own, but both together sound funny. I think it might be worth changing to order of this sentence as well, so that it starts with the character waking up and then moves on to the sun.

It was like the planet was a clock and the battery failed; like the hands had just stopped and time stood still.

this is a lovely little metaphor

I have no idea what happened, I’m not a scientist,

be careful that you've changed tense here. "I HAD no idea...I WASNT a scientist."

but the planet went into darkness at 1600 hours on December 21st, and stayed in the carpet of blindness for what seemed like 7 days.

Carpet? This is a bit odd, although i know what you are trying to convey. Try find another way of saying this

All I knew was I should have been dead, 7 days will out the sun,

This should read; "seven days without the sun."

The sun was what I thought a beckon of hope.

beacon of hope. Maybe this would be better as "I thought the sun was a beacon of hope."

I still remember how it looked. I may have spent most of my time on the West Point Military Academy base, but I recollect how the city looked; now my home is in ruins.

Watch your tenses again.

The bigger buildings are still falling down and half missing, the smaller buildings gone, the roads are gone, smashed into a thousand pieces; once where there were bridges, now are just piles of rubble. The smell of toxins is still strong, every breath taken felts like a punch in the gut because of the smell.

Tenses again!

...not since my mother had walk out on us when I was 10.

"when I was ten."

He smiled. Knowing I thought the world of him.

"He smiled, knowing i thought the world of him."

Then the plant erupted into a flash of light.

planet.

I saw all of this tragedy from the out skirts of New York at my father’s house where I was peeling potatoes for my Dad’s favourite potato dish… ‘Don’t think, it’s in the past, think about now, about living another day. Forget about the past.’ And so for now, I forgot.

Start a new paragraph after "potato dish"

27 more days have passed; 27 more nights, 27 more dreams.

twenty seven.

Every night the pain in my head, and my heart expand, like the memory is trying to break away from my mind to torment me even more.

tenses again. was! The whole next section is rife with confused tenses. For example;

Slowly I break down in tears. I cried without resistance.

My father Tony O'Connor was a scientist, and he saved my life. My name is Natasha O’Connor; I was a Major in the United States Army in the year 2012; and now because of my father I am possibly the only survivor of man’s biggest mistake.

I love this final line. it's great!

All in all, I enjoyed your story! I thought it was imaginative and well thought out, although your excecution needs a little tweaking. Your biggest and most prominent problem is with your tenses. You switch between past an present in the same sentence! Just make sure you keep an eye out for this, because its so simple to fix Also, i noticed a lot of typos. I didn't correct them all, but keep an eye our for these too.My advice would be just to proof read everything you've written, and then read it again! Maybe even get someone you trust with your writing to go over it, because its sometimes hard to notice these things as the writer of the piece.

Anyway, I hope i have helped!! Keep writing!!