Excavation and Disposal of Japanese Knotweed

When effective on-site management of Japanese knotweed is not possible, the plant must be excavated and disposed of at a suitably licensed waste management facility.

 

Landfill Disposal Considerations
Disposal to landfill should only be considered as a last resort due to the high costs associated with this method. Strict precautions must be taken to prevent any material from escaping during transport. A licence from the National Parks and Wildlife Service (NPWS) is required for the transportation of the excavated material.

Requirements for Licensed Waste Facilities

 

The excavated material must be taken to a waste facility that meets the following criteria:

• The facility has been notified in advance about the nature of the waste.

• It holds the appropriate licence to accept Japanese knotweed material.

• The facility has confirmed its readiness to receive the material.

 

Pre-Excavation Treatment
At least two weeks prior to excavation, the invasive alien plant species (IAPS) should be treated with a non-persistent herbicide. Products containing glyphosate that do not persist in the environment are suitable options, as they minimise the risk of groundwater contamination.

 

Under no circumstances should persistent herbicides be used if excavation and disposal are planned, as they could result in the material being classified as hazardous waste.

 

Site Hygiene and Risk Mitigation
To reduce the risk of spreading Japanese knotweed to other areas during excavation, it is essential to implement robust site hygiene practices. Recommended measures include:

• Fencing off and clearly marking areas of infestation to restrict access.

• Avoiding the use of tracked vehicles in contaminated zones to prevent further spread.

• Pressure washing vehicles before they leave infested areas, using designated wash-down areas to contain any plant material.

• Ensuring adequate supervision throughout the excavation and disposal process to maintain compliance with all procedures.

 

Following these guidelines helps ensure the safe and effective management of Japanese knotweed, preventing contamination of other areas and protecting the environment.