The site, formally railway sidings, had long been overgrown with patches of established knotweed.
Passing the site to catch a train to London for a knotweed survey, an Elcot staff member noticed that the site was being cleared and that plant was moving through the knotweed, spreading it through the site. He called the office and another Elcot surveyor called on the site within half an hour and explained the issues of knotweed contamination to site management, who were unaware of the issues that knotweed on site could create.
The following day, Elcot provided a costed management plan to dig, sift and bury on site, as well as to monitor to ensure eradication. This was accepted and following fencing off of both disturbed locations, Elcot got to work.
Tracked and wheeled machines had caused surface spread-out of the area, resulting in difficulty in identifying the core plant location.
A careful dig of one area, which had been disturbed on the surface, traced back rhizome growth laterally, but significantly, on this old railway site the depth was not more than approximately 1 meter generally with occasional pockets extending down to over 2 meters.
Differing layers of made up ground provide either friendly or hostile conditions for Knotweed growth but a clay layer was the limiting factor in depth on site.
A scrape back of the surface exposed one yellow-orange root crown near 1 meter wide.
The excavated ground is sifted for knotweed rhizomes, while the treated and processed material is buried on site, at a shallow depth with a 1 meter cap of sub and topsoil, with no encapsulation.
The whole works were completed in just under a week from instruction, and during monitoring visits in the subsequent months, a few small shoots of knotweed were identified and removed by hand. These appeared to have been be from caused by surface spread from contractors plant before Elcot were on site.
Formal and informal monitoring during the subsequent years has not identified any return of knotweed anywhere on the site.