Following one of our in-depth surveys, we will select the best management plan depending on the extent of the infestation. To manage the spread of the weed on your land, our expert team will often employ a range of methods. One of these methods is Excavation and Removal Treatment.

Excavation & Removal

Method Four: Off-site disposal

Duration: On-site work followed by 2 years of monitoring

The excavation and removal method is when the Knotweed and the underground soil is excavated and transported offsite to a licensed landfill site. 

Although Excavation and Removal of Japanese Knotweed material off-site is a legitimate and swift control option with advantages for development sites if done correctly with the right licences, we are not advocates of pursuing this method as it raises significant logistical challenges. There is a high risk of the Knotweed spreading when transporting it and the cost of transporting the material to a designated and licensed landfill site are amongst other issues. 

In this scenario, there is no time to carry out a 5-year herbicide treatment programme, especially if you have plans to excavate ‘Controlled Waste’ soils and develop within the affected areas. In these cases, immediate Knotweed treatment via physical excavation and licensed disposal of the Controlled Waste is the best option.

Experienced excavators chase the Rhizome network using CAD site plans rather than excavating indiscriminately. This minimises costly unaffected soils from being removed from the site.

Following successful excavation and disposal, you are provided with a 10 Year Insurance Backed Guarantee, from a leading insurer, which becomes valid once the excavation works and monitoring period has been completed on-site.

Development work can commence as normal once the site is finished being remediated. Typically an excavation can take 1-2 weeks to complete and are monitored on a bi-annual basis for 2 years following completion to ensure no re-growth occurs. For our private households and residential gardens, our ‘rapid excavation service’ can excavate Japanese Knotweed from your garden within days.

There is a duty of care required under the Environmental Protection Act (EPA) 1990 for transporting and disposing of Knotweed. We are, however, happy to act in a consultancy role as clerk of the works providing certain conditions are met with the landowner/developer.

Benefits of excavation include:

• Knotweed can be completely removed from a site very quickly
• Development and landscaping works can commence the following remediation with no restrictions
• 10-year insurance backed guarantees available
• Mortgage compliant treatment method
• Can take place at any time of year

You should consider that the cost of excavation can be higher than other methods. Excavation must be carried out by a recognised specialist to ensure legislation is complied with and that soil is disposed of by a licensed company.