Oiled bedding sand?

[sdz]

API 650 App B recommends bedding tanks on "clean dry sand". I know a lot of engineers specify oiled sand. Is oiled sand a good idea or are there reasons why it should not be used?

 

[JStephen]

It's generally been eliminated for environmental reasons.

 

[Stl63]

Clean dry sand is difficult to keep in place when placing the bottom plate, it depends on site conditions as well. Wind can easliy displace sand, and make it difficult for erector. I have worked with Tank vendors who like to use a fiberboard (1" to 1-1/2" thick) in place of sand.
Oiled sand will work, perhaps environmental reasons, but it is just a light spray, and it's contained by the slab and grout, shouldn't be leaking into ground water or causing any other major issues.

 

[MJCronin]

sdz...

Many CPI companies and consultants have developed and specify complete under-tank standards including foundations, membranes, asphalt-board etc.

The statements in API are neither complete nor definative about under-tank configurations.

Oiled sand in no longer in use.....the oil was used to help the sand conform to the tank bottom during the first fill. In most appllications asphalt board has replaced oiled sand.

http://www.ast-forum.com/astforum2005/_discAST/00000951.htm

Consider searching and posting on a website devoted to storage tanks:

http://www.ast-forum.com

Is this worth a "star" ?

My opinion only

-MJC

 

[SJones]

Oiled sand also hinders cathodic protection of the tank bottom. API RP651 contains guidance on pad materials.

Steve Jones
Materials & Corrosion Engineer

http://www.pdo.co.om/pdo/