Acidity of Rock Backfill
Acidity of Rock Backfill
(OP)
I was recently asked what provisions are being made for the acidity in rock backfill and it through me for a loop. Anyone have any experience with this? We are designing a 24" steel gas pipeline that will have corrosion protection. In the roadways it will have rock backfill. I think this is a non issue but interested to hear if anyone has dealt with this before.





RE: Acidity of Rock Backfill
For a high risk project such as a gas pipeline, you should have a corrosion engineer do an investigation and give recommendations. This will require material sampling along the alignment and if you are importing bedding or backfill material, you can sample and test that also.
RE: Acidity of Rock Backfill
RE: Acidity of Rock Backfill
RE: Acidity of Rock Backfill
RE: Acidity of Rock Backfill
I would make a call to the local Public Works Director and see if this has been a problem before. Also, experienced contractors can give you some advice on local conditions. If the pipe already is going to be protected from corrosion with a special coating or cathodic protection, then this probably is a mute point. If you have a hint you might have a problem, then put the condition in the specs that the pipe must be corrosion protected according to ASTM xxxx.
But over design is not the mark of a good engineer. Make sure you need the protection before incurring the extra costs.
RE: Acidity of Rock Backfill
7th International Conference on Acid Rock Drainage
http://technology.infomine.com/acidminedrainage/we...
Acid Rock Drainage (ARD)
http://bioteq.ca/services/solutions-for-mining/aci...
RE: Acidity of Rock Backfill
Richard A. Cornelius, P.E.
WWW.amlinereast.com
RE: Acidity of Rock Backfill
I just read it!
f-d
¡papá gordo ain’t no madre flaca!
RE: Acidity of Rock Backfill
RE: Acidity of Rock Backfill
Add this sentence to your riprap specification:
"Material used shall be free of acid-forming material and toxic-forming material and riprap shall comply with the durability requirements."
Acid forming rocks are normally present at mine sites because the same metal ores that are mined for metals are the sulfides that have the potential to form acids. Waste rock from mines may be acid forming and is not the same material as quarry rock.
See the linked article discussing rock.
http://aptalaska.com/upload/pdf/Acid_Rock_Drainage...
RE: Acidity of Rock Backfill