RPA compromised - solution

[Lowestoft Firewood]

Got a mate who has fairly seriously compromised the RPA on 3 trees. 

 

One very large Cedar of Lebanon and 2 smaller Western Red looking Cedars.

 

He was aware they had TPOs but completely unaware that the roots are protected in the same way as branches ?.

 

He has had a 22 ton excavator in  and scraped around 50mm off the entire site including all round the smaller trees and half way round the large cedar, laid a membrane then crushed concrete over the top to about 100mm. 

 

The council have (understandably) thrown the toys out the pram because of the compaction.  I am really asking for advice from you guys what he could do to rectify the situation long term and if anyone has had any experience in similar situations. 

 

Thanks in advance for any help ?

[daltontrees]

The damage is already done. Best not to do anything else on site without the Council's agreement. Meantime, grovel.

[Dave177]

In this situation (if the trees are to be retained and have not been too seriously damaged) we usually do something along the lines of remove crushed concrete and membrane, decompact soil 1.5 times RPA, mulch decompacted area using mulch/compost and biochar, heavily water.

Obviously any work need to be approved by the LPA 

If your friend wants more information etc then they can drop me an email [email protected] 

[Lowestoft Firewood]

Thanks Dave he may well be in touch, I hope we can remove the 2 smaller ones and retain the larger. Unfortunately he really does need a drive near the house so any suggestions of a solution to that too would be great. Something that drains naturally and doesn't compact... Is there such a thing?! Thinking grid / mesh type thing.

[benedmonds]

2 hours ago, EdwardC said:

Stop digging a hole for yourself. ....

I don't think it was a hole..  "scraped around 50mm off the entire site."

 

Cellular confinement systems with no dig might have been used before the damage to install a drive over RPA but remediation would involve removing concrete without having plant travelling on the RPA and decompact/mulch..

 

[Khriss]

22 ton - I'd bet crown has had a beating- poor trees . Amazing that 360 drivers ain't more aware ..now wheres Tetchy Paul K

[Gary Prentice]

Get very pro-active with the Tree Officer for a start. 

 

This will create a lot of work for him/her, so try to take the reins by putting forward a good mitigation plan for the LA's agreement.

 

Start with a method statement to remove the impermeable new layer that isn't going to create more compaction. There's a section in BS5837 on removing hard surfaces in the RPA for guidance. Once that's sorted the level of compaction and root damage/severance will need to be assessed. A soil compaction tester like the Dickie-john would be useful. 

 

Just take it one step at a time and don't do anything without the agreement of the LA.