In ground oil line abandonment

dbldangertilt

We removed our oil fired boiler and hydronic setup and are looking to eliminate the remaining components including the burner. Any recommendations on how to handle the oil feed and return lines? How do I cap them temporarily and/or permenantly?

Thanks

Jamie Hall

Blow them out and make sure there is no residual oil in them at all, and then cap them at both ends.

What are you doing with the tank?

STEVEusaPA

Take the check valve off before blowing it back.

Jamie Hall

The assumptions I make, @STEVEusaPA ... sigh... I assumed they would disconnect right back the elbows... oh well.

EBEBRATT-Ed

Yes, what are you doing with the tank?

dbldangertilt

Haven't decided on what to do with the inground 675 tank. Soil samples came back negative. Has about 170 gals left. Would prefer removal vs abandonment (slurry fill).

What caps are typically used for the lines? Trying to diy as much as possible. 

Jamie Hall

I'd agree that removal of the tank is the best approach. Remove it, take soil samples of the sides of the pit, continue soil removal until the samples are all negative. I'd use threaded caps on the lines.

However... this is not really a diy job. That tank, even after you get it pumped out, is going to be heavy. Further, it's structural integrity is going to be questionable. There are companies that do this for a living and know what they are doing -- and, perhaps more important, carry insurance against problems during removal and down the line if contamination is suspected. Try contacting your public health people or environmental protection people for suggestions.

STEVEusaPA

dbldangertilt said:

...What caps are typically used for the lines? Trying to diy as much as possible. 

Whatever you do, unless you break out the concrete you're going to have 2 pipe stubs.
After you blow out the lines, you can unscrew both elbows and just put on some regular steel caps. Hard to tell by looking buy I think they are 1/2" or maybe 3/4". Is it steel pipe back to the tank?

If you get the tank dug out, they can probably get the supply/return removed all the way back to the house. If that's the case I'd just fill them with cement at the wall, then cut the concrete floor around them and get those lines cut below the floor and patched.

EBEBRATT-Ed

@dbldangertilt

If one or both of those oil lines extend to the bottom of the tank and where you disconnect the lines is lower than the oil level in the tank you will likely get oil syphon to you when you disconnect the lines.

You will have to cut the lines at the high point or work fast

dbldangertilt

Jamie Hall said:

However... this is not really a diy job. That tank, even after you get it pumped out, is going to be heavy. Further, it's structural integrity is going to be questionable.

Thanks. Yes I was going to contract out for tank removal but try to cap the lines in the meantime.

EBEBRATT-Ed said:

If one or both of those oil lines extend to the bottom of the tank and where you disconnect the lines is lower than the oil level in the tank you will likely get oil syphon to you when you disconnect the lines.

You will have to cut the lines at the high point or work fast

This is exactly what I think will happen having disconnected lines for repair/maintenance before. A heating oil company will extract the remaining oil for $350 less 50 cents per usable gallon likely leaving 3-5 inches of sludge. I assume we may still get oil in the lines after extraction.

@STEVEusaPA

Thanks. Not sure if the lines are steel all the way back to the tank, the 2 nubs are the only exposed portion.

EBEBRATT-Ed

@dbldangertilt

Unless the old lines rotted out underground and were replaced with copper outside then they are steel.

Be cautious some of the really old jobs had the suction line coming out of the bottom of the old tanks. This became illegal at some point but used to be done When this was done those jobs were usually 1 pipe.

That was common back in the 20s & 30s.