In most cases it is possible to immediately eradicate Japanese knotweed. This would be removal by means of excavation with a guarantee of any length.
It is important to understand the Japanese knotweed that's visible above ground has a large network of underground rhizomes and roots that can't be seen. These rhizomes have been recorded to reach up to three metres deep and spread out up to seven metres in all directions. To give some scale to how large the rhizomes can grow, see the photo taken at a recent excavation.
Instant Japanese knotweed eradication can sometimes involve excavating all the soil to the full depth and spread of the rhizomes and roots, to ensure that all affected ground is removed. However our experience and expertise ensures accurate identification of the rhizome in the ground and this in turn reduces the volume of excavation (and subsequently your costs) required to remove the knotweed.
Japanese Knotweed Removal
We will advise you of the method appropriate to your property following feasibility and cost efficiency assessment. The excavation method (if possible) will depend on the type of access available to the Japanese knotweed and the area of contaminated land. Immediate removal of the Japanese knotweed can be achieved via the following methods.
Excavation and Cart-Away (Dig 'n' Dump)
A Dig and Dump operation provides instant eradication. The Environment Agency's 2013 (version 3) 'The Knotweed Code of Practice' puts emphasis firmly on reducing quantities of waste removed to landfill. With this in mind we accurately identify the full extent of the rhizomes and root system and in doing so ensure that only knotweed material – and not clean soil – is excavated and removed from your property (reducing your costs).
Reduced Level Excavation and Capping (Dig 'n' Cap)
A detailed understanding of the property; current and proposed use and any re-development plans of the area affected by the knotweed, may enable us to excavate the knotweed to a depth where a capping root barrier membrane can be installed to eliminate any future knotweed problems and allow for re-instatement or construction work without risk of damage to the membrane. The arising knotweed waste from this activity can either be removed off-site to a specially licensed landfill or disposed of on-site as a burial or relocation.
Excavation and On-Site Burial (Cell-Burial)
If there is adequate space within the boundary of the property it may be feasible for the excavated knotweed to be buried on-site, encapsulated within specialist root barrier membranes. Most importantly in accordance with the Environment Agency guidelines, the top of the burial cell should not be less than 2m below the finished site ground level and the local E.A. office Environment Protection Team should be informed at least one week prior to the burial activity so they can verify that only Japanese knotweed material (and not any other contaminate) is to be buried. Please note that the creation of an on-site burial cell is prone to settlement and it is recommended they be located beneath areas of soft landscape where possible.
Excavation and On-Site Relocation (Relocation)
On a larger property, excavation and relocation of the Japanese knotweed can prove to be a cost-effective and sustainable remediation solution. The knotweed is quite simply moved from the area of the property where it is either; presenting a property risk or impeding property improvement works (re-development or landscaping), to another area of the site. At its relocation point it can be treated with herbicide but it is important to note that this will not remove the knotweed contamination and the Environment Agency will only allow the removal of the treated material from the property if it is classified as controlled waste.
Controlled Waste Disposal
If we remove the excavated soil containing Japanese knotweed from your property it is immediately classed as a 'controlled waste' and must be handled and disposed of in accordance to the Environmental Protection Act 1990 and Duty of Care Regulations 1991. The controlled waste will be taken to a specially licensed landfill site and we will retain full waste tracking records.
Our price will include the cost of Landfill Tax which has been rising annually for the past few years, and is set to continue to rise rapidly for the foreseeable future. In the Budget of 2007, the Chancellor of the Exchequer announced that standard Landfill Tax will rise from April 2008 by £8 per year, meaning it will reach £72 +VAT per tonne by 2013 and £88 per tonne by 2015 (assuming the level of increase stays the same).
Japanese Knotweed Excavation Costs
An immediate removal programme (using the methods listed above) with two year guarantee (or a longer if an option to extend the guarantee period is chosen) will cost from £4000 +VAT.