People searching for the cost of knotweed disposal usually find either the cost of a treatment programme or a per-tonne figure with no context. Neither tells you what it will cost to have excavated knotweed waste taken off your site. That cost has two parts, haulage and disposal, and both depend on the particular job. For what the service covers, see Japanese knotweed disposal.
Factors affecting disposal costs
- Quantity and weight. Disposal is charged on weight, so the tonnage is the biggest single factor.
- Composition and classification. Soil containing knotweed alone is treated differently from soil that is also chemically contaminated. Hazardous material costs considerably more to dispose of.
- Collection location. Where the site is determines which authorised facilities are within reach.
- Transport distance. Fewer facilities accept knotweed waste than ordinary soil, so the journey can be longer than for general muck-away.
- Vehicle requirements. A full articulated load costs less per tonne to move than several small ones, but only if the site can take the vehicle.
- Loading arrangements. Whether your machine loads the lorry, or a grab lorry is needed, and how long each vehicle is on site.
- Disposal facility charges. The facility’s gate fee and the landfill tax that applies.
- Testing and pre-acceptance requirements. Analysis the facility needs before it will agree to take the load.
Tonnes versus cubic metres
Excavations are measured in cubic metres; disposal is weighed in tonnes. The conversion depends on the soil. As a rough guide, a cubic metre of excavated soil weighs somewhere between one and a half and two tonnes, more if it is wet clay and less if it is dry and loose. Soil also bulks up when it is dug, so a hole of ten cubic metres produces more than ten cubic metres in the lorry. If you can only give us dimensions, tell us the soil type and we will estimate the weight. The final charge is based on the weighbridge ticket at the receiving facility.
Haulage charges
Haulage is normally priced per load. It reflects the distance to the facility, the vehicle, the time allowed for loading and tipping, and any restrictions on when your site can be accessed. Part loads still need a vehicle and a driver, so small quantities cost more per tonne to move than full loads. Waiting time on site beyond the allowance is usually charged. See Japanese knotweed haulage.
Testing requirements
If the receiving facility needs chemical analysis to classify the soil, or further testing against its acceptance criteria, that is a cost to allow for, in money and in time. It is almost always cheaper to have the sampling done before excavation starts than to have loaded soil waiting for results. If analysis shows the soil is hazardous for reasons unrelated to knotweed, the disposal route and the cost change.
Facility acceptance
Landfill disposal carries the facility’s own charge plus landfill tax: Landfill Tax in England, Scottish Landfill Tax in Scotland and Landfill Disposals Tax in Wales. The rate depends on the material. Knotweed-contaminated soil is not inert waste, and it should not be assumed that it qualifies for the lower rate that applies to some inert materials. Facilities also price according to the handling the waste needs. We obtain a price for your specific material from a facility that has agreed to accept it, and we do not disclose individual facility charges.
Bulk project pricing
On larger projects the price per tonne usually improves, because vehicles run full, loads can be scheduled back to back and the tonnage can be agreed with the facility in advance. We quote bulk work as a rate per tonne or per load for the expected quantity, with the assumptions stated, so that you can budget for the dig.
Keeping the cost down
- Segregate affected soil from clean soil. Every tonne of clean soil mixed in is paid for at the knotweed rate.
- Remove only what your specialist says needs to go.
- Have any analysis ready before you ask for a price.
- Give accurate quantities, so the right vehicles are sent.
- Make sure the lorry can get in, be loaded promptly and get out.
Quotation requirements
To quote we need the site address and postcode, the type of waste, the estimated quantity, the date you want it collected, how it will be loaded, the site access and any analysis or reports you hold. Photographs help. Our quotation states what is included, the basis of the tonnage and what would change the price. Request a quote or call us with the details.