Liam, the #BeastOfBexley, of South East Rubbish, went and visited that illegal landfill site near the River Cherwell (between #Kidlington and #Oxford) so that you do not have to.
https://youtube.com/watch?v=o829lQd619c
Liam regularly voluntarily hand-clears fly tipping from the sides of the A2 et al. in Bexley and environs. But I suspect that this, clearly done on an industrial scale, is well beyond Liam's means to clear.