BACKGROUND
We were instructed by our client – A building contractor to carry out a survey within the Yardley area as Japanese Knotweed was found on site whereby a new perimeter wall was being developed.
SITE SURVEY
During our site survey, we reviewed all options and it was decided that dig and dump method would be unrealistic and very costly for the client along with not enough space to use this methodology with plant machinery.
The preferred methodology would be as follows:
• An initial clearance of all the above ground knotweed vegetation, the knotweed will be placed in dumpy bags and stored on site behind secure fencing for the duration of the contract.
• Biosecurity boot wash and machine washing area to be installed at the entrance to the site.
• A temporary geotextile barrier will be placed on the ground between the wall and the Heres fencing and then the client will provide plywood sheets over the barrier with a further amount of recycled stone to allow a 13T excavator to work within the site, away from the knotweed to prevent any cross contamination.
• Knotweed Services (UK) Limited to provide a site supervisor/manager to supervise the removal of the wall and footings in the area of the knotweed.
• Knotweed Services (UK) will manually screen any material that arises from the new foundation construction and place any rhizomes in dumpy bags and place the bags in the secure biosecurity area on site.
• Once all the knotweed material from all the areas has been bagged and sealed, these will then be transported to licensed landfill in Cheltenham under EPA1990 Duty of Care guidelines.
• Full waste transfer and disposal tickets will be provided.
• Once the site work has been completed Knotweed Services (UK) will return to site and remove the barrier and check for any potential spread.
• The knotweed areas will then be placed under a Japanese knotweed management plan for 2 years to completely eradicate the knotweed from all the areas. This will consist of 3 visits each growing season to treat the knotweed with herbicide for a period of 2 years.
• A full biosecurity report will then detail all the elements of the works and outline all the procedures used to minimise any potential spread of knotweed within the areas.