In article ,
"david taylor" writes:
|
| I don't think it is much of a problem on the compost heap. We found a patch
| of sump oil when builders had left our first house-all traces had
| disappeared after a season, lawn and borders growing around it.

There are major differences between cooking oil, mineral oil, and the
heavier tars extracted from that. The first type of oil is widespread
in the biosphere, and is readily broken down by bacteria if there is
any associated water and oxygen. The second is rather different, and
needs specialised bacteria to break it down, so takes longer. The third
is durable over a period of years or decades, even in the presence of
water and oxygen.

As lots of people have said, cooking oil on the compost heap is fine,
unless there is enough to exclude water or oxygen.


Regards,
Nick Maclaren.