Product on Fire in tank Excavation During Removal

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mrdv
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Product on Fire in tank Excavation During Removal

Post by mrdv » Wed May 03, 2017 6:37 am

Looking for advice.... Here is the situation. We have removed (3) gasoline tanks and are going to install new tanks. The excavation has been shored. We know we have contaminated soil. We are excavating the tank hole within the shoring. We have hit a pocket of raw product. This pocket has sparked and caught fire. This fire continues to spark when we take scoops with the excavator bucket. We have stopped digging and the fire has gone out. My questions are.

What is the safest way to remove this dirt?
What is the safest way to prep this tank hole? ( I will not put anyone in this hole in its current condition)
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CherokeeUST
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Re: Product on Fire in tank Excavation During Removal

Post by CherokeeUST » Wed May 03, 2017 9:05 am

First, did you video tape the fires? Those are always fun to watch.

Have you tried using a vac truck to pull out the liquids and loose materials?

You need to find some way to inert the area so the fire triangle cannot be completed. I'm sure your local LUST office has dealt with this before and will have solutions for you.
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ZMiller
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Re: Product on Fire in tank Excavation During Removal

Post by ZMiller » Wed May 03, 2017 6:23 pm

What condition is the excavator in?

Are you getting a flash when the bucket is in soil or are you flashing when the bucket is dipping in empty or being pulled out loaded.

Sounds like you have a grounding issue with your equipment. Position and more adequately ground your equipment. Eliminate the earth static ground spark with a heaver grounding strap and grounding rod. Or you have an electrical short to ground on the excavator frame through to the boom and bucket that needs to be found and repaired.


To confirm grab on to a metal part of the excavator and kneel with your knee touching the ground for a few seconds. Do you feel anything like a tingle from the metal contact point say up to around your elbo or shoulder?

There are however better ways to check for equipment shorting discharges to ground.
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hardworking
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Re: Product on Fire in tank Excavation During Removal

Post by hardworking » Thu May 25, 2017 4:36 am

I hate to be critical, but something doesn't add up in my mind. The OP said they were working on gas products, and a fire started with a spark. Well, from what I've seen with gasoline, it should have been an explosion (vapors igniting) not just a fire.

You can keep a vapor from burning 2 ways, by having the atmosphere around the product either above the UEL or below the LEL (that's upper and lower explosive limits). It will be difficult to keep that hole in either condition.

I'd love to know more about this "spark". Where is it happening? Is the bucket hitting the shoring? Is it a step voltage from stray current in the ground?

I hope y'all got this taken care of and I'd love to know what you did.

nelsonpw
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Re: Product on Fire in tank Excavation During Removal

Post by nelsonpw » Tue Jul 25, 2017 9:37 pm

No updates on this thread for two months so it's safe to assume that the explosion decimated the area leaving all involved either dead or mortally wounded. Either that or there's a new Buc-ee's in San Antonio.
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MariVak
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Product on Fire in tank Excavation During Removal

Post by MariVak » Mon Aug 27, 2018 1:28 pm

You said spray foam. Home Depot or Lowes has cans of fire resistant foam. Its in the red cans.

GariBiott
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Product on Fire in tank Excavation During Removal

Post by GariBiott » Fri Feb 15, 2019 9:16 pm

Just curious - when the suction fitting is at the top of the tank, is there a stand tube from the fitting down to the bottom of the tank?

Ken

mulgoaquarries
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Re: Product on Fire in tank Excavation During Removal

Post by mulgoaquarries » Mon Apr 08, 2019 1:46 am

You can keep vapor from burning 2 ways, by having the atmosphere around the product either above the UEL or below the LEL (that's upper and lower explosive limits). It will be difficult to keep that hole in either condition.

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