Tarmac In Vegetable Patch Soil

Question

I recently had a landscaper in to terrace part of the garden where a very large cedar tree had been felled last year There was a tarmac path around the edge of the area. I thought this was being removed from site when broken up and lifted However after he had finished and I was digging the area I wanted to use as a vegetable patch, I discovered a lot of tarmac in the ground I have been double and triple digging the area and removing as much of the tarmac as I can reasonably find I have been researching and can’t find any definitive articles on how bad this is for the soil, or what levels of pollutants can leach from the tarmac/asphalt into the soil and whether the amounts would be above or below safety limits Any advice gratefully received Mike Walsh

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Answer 1

Alone, asphalt does leach quite a few contaminants into the soil. If this has been used for any motor traffic, then this significantly increases the contaminants that could be present.

I would have your soil tested by the local authorities for agriculture in your country. A thorough soil test will give you a very accurate analysis of what it contains. This will help you to start the remediation process.

Answer 2

Hello again
Thanks for the reply
The tarmac in question was a garden path 3 foot wide and about 30 foot long and 20 yards from the minor village road outside the house
It was only dug up a few weeks ago and was in the ground for three weeks before I discovered it, done by the so called landscape gardener
Very cross with him
I have spent the last three weeks with my stepson digging it out and bagging it
I have gone down two foot in the whole area and gone about 18 inches to the side of where I will be planting to avoid leaching from remaining tarmac that might be adjacent in the ground
I am hoping the leaching in these few weeks will have been minimal
We have had next to no rain in this period
I will get the soil tested
Have you any other thoughts on the situation?
Regards
Mike