--- title: "The Base Needed 1.9 Million Cubic Metres Out. The Hill Lost 41,000." dek: "Two survey firms, working blind, computed seven decades of volume change from film and lidar this newspaper paid for. The hill has lost 41,000 cubic metres, all of it in one road cut on the north side." kind: nullresult (The Null Result) desk: Shadow Governance author: Marcus Oyelaran and Nadia Ferreira-Ost (fictional) published: 2026-08-22T06:00:00Z url: https://theyburied.com/article/hill-lost-forty-one-thousand tags: photogrammetry, lidar, Monmouthshire, service reservoirs, haulage genre: satire status: fiction — nothing in this story happened; every person, source and document is invented --- # The Base Needed 1.9 Million Cubic Metres Out. The Hill Lost 41,000. *Two survey firms, working blind, computed seven decades of volume change from film and lidar this newspaper paid for. The hill has lost 41,000 cubic metres, all of it in one road cut on the north side.* Twelve levels under Mynydd Cadlan would require about 1.9 million cubic metres of rock to be cut out of it. Broken rock swells. Hauled away, that becomes roughly 2.8 million cubic metres of muck, which is about 93,000 lorry movements on two lanes that carry weight limits — and 93,000 is the generous figure, calculated at 30 cubic metres a load. A tipper that can actually get up those lanes carries nearer twelve. Between 1953 and 2024 the hill lost 41,000 cubic metres. All of it is in one place, on the north side, in a shape that is unmistakably a road cut. ## Three surfaces, bought and published We did not ask whether there was a base. We asked how much rock had left the hill. Three surfaces were purchased. The 1953 and 1971 aerial survey sorties were scanned at 12 microns from the original negatives, not from prints, which cost five times as much and was the single most important decision in the reporting. The third is an airborne lidar pass flown to order in October 2024. Two survey firms then computed the volume change between them. Neither knew about the other. Neither was told the hill's name or the reason for the job until its report was delivered; both were told it was a landfill volumetric dispute. Pellworth Geospatial returned a net loss of 40,100 cubic metres, plus or minus 3,400. Cadair Survey Partnership returned 42,600, plus or minus 2,900. They disagree for six pages about the 1971 film's interior orientation, and both reports run in full with this story. > **Figure:** What twelve levels would have cost the hill, against what the hill actually lost — see https://theyburied.com/article/hill-lost-forty-one-thousand ## The trucks were real The most striking thing about this story is that the traffic people remember actually happened, in the volumes they remember, in the years they remember. Between March 1968 and August 1971, a Monmouthshire county highways contract moved 38,400 cubic metres of shale out of the north cut and built it into an embankment eleven miles away. The tender, the measured works, the weighbridge tickets, three contractual claims and a dispute about Sunday working are in the county record office in nine box files. Our correspondent read them over eleven days and every haulage ticket is transcribed and published with this piece. The contractor's daughter still has her father's day book. It records the dust, which was orange and got into the bread; two broken leaf springs in one week in June 1969; and what Idris Prydderch thought about being asked to run on a Sunday, which was a great deal. > He came home orange for three years, and then the hill went quiet, and thirty years later a man on the television said it was a bunker. > > — Gwenllian Prydderch-Amis Three years of genuine, memorable, unpleasant traffic. It matches the road cut in the lidar to within an amount two survey firms would argue about. It does not touch 93,000. ## One room There is an underground structure at the centre of the story, and it exists. It is a covered service reservoir. Nine hundred cubic metres, built in 1954, with a concrete roof under about a metre of turf, an access hatch, a fixed ladder and a padlock. The undertaker's asset register gives its dimensions. The visit log begins in 1998. Nine hundred cubic metres against 1.9 million is a ratio of about one to two thousand. The room is real. The eleven floors were added somewhere between the hatch and the telling. ## What would defeat this test We will state it plainly rather than leave it for a correspondent to find. Our method measures the outside of a hill. If spoil was driven out sideways through an adit and tipped into the worked-out void of the disused Blaenserw drift, two valleys over, it would never cross the surface we surveyed and this entire article would be worthless. We obtained Blaenserw's subsidence monitoring from 1961 to 2019. There is no settlement anomaly, no inflection in the record, and no change in the pumping regime. That is not the same as proving nothing went in. The drift was levelled twice a year by one man, and a hundred thousand cubic metres arriving slowly is exactly the shape of thing that record would miss. ## What this desk takes from it Emlyn Cadwaladr-Nunn's reply is printed below at his requested length, and it takes something from us. He never said twelve; a television programme did. He says the finding is not the volume but the four-line refusal that a ministry has sent to this valley for fifty-one years about a hatch containing drinking water. We measured the hill because the hill could be measured. We have no method at all for the four lines. ## Sources (invented) - Pellworth Geospatial, Photogrammetric reconstruction, 1953 and 1971 survey film — Commissioned by this newspaper; told the job was a landfill volumetric dispute and given no other context until after delivery (February–May 2026) - Cadair Survey Partnership, Second reconstruction, blind to the first — Given the identical scans and the same cover description, with no sight of the first report and no contact with its author (March–June 2026) - 1953 and 1971 aerial survey sorties, Original negatives, national air photograph collection — Scanned to order at 12 microns from the negatives rather than from prints; scans paid for and republished by us (January 2026) - Monmouthshire county highways contract file, 1967–1972, Nine box files: tender, measured works, weighbridge tickets, three claims and a dispute about Sunday working — Read at the county record office over eleven days; every haulage ticket transcribed and published as a spreadsheet (April 2026) - Gwenllian Prydderch-Amis, Daughter of Idris Prydderch, haulage contractor — Interviewed at her home twice; lent us her father's day book for nine days and read the full draft before publication (May and July 2026) ## What we could not confirm - Whether anything was tipped into the disused Blaenserw drift two valleys over. That is the one route by which spoil leaves a hill without touching a public road, and it would defeat this entire test. We obtained the drift's subsidence monitoring, 1961 to 2019, and found nothing anomalous — no settlement, no inflection, no change in the pumping regime. That is not the same as proving nothing went in. Monitoring that sparse would not see a hundred thousand cubic metres arriving slowly. - The 1953 surface's control. Photogrammetry from historic film needs ground control, and we have 61 points from the survey's own trig list. Eight of them no longer exist. Both firms handled the gaps differently and their two answers differ by 2,500 cubic metres, which is the honest size of our uncertainty. - Whether the reservoir has ever been entered by anyone other than the undertaker's own staff. The padlock is a water company padlock and the visit log begins in 1998. Before that there is no log, and the men who would have kept it are dead. ## Right of reply **Emlyn Cadwaladr-Nunn, who has been describing the hill in print and on air since 1979** (Replied by letter on 14 August 2026, running to eleven pages, and asked that it not be cut. Printed unedited.): > I have never said twelve. I want that first because you have put it in your headline and it is not mine. > > What I said, in 1979, in a pamphlet of which four hundred were printed, was that the hill had been worked between 1968 and 1971 by men who were not from the valley, that the works were larger than a road cut required, and that nobody in authority would say what they were. Twelve levels came from a television programme in 1994 that did not interview me and did not need to. I have spent thirty years being asked to defend a number I did not produce, and now a newspaper has spent forty-one thousand pounds disproving it and has put my name under it. > > That is my first complaint and it is a small one. Here is the larger one. > > Your method measures the outside of a hill. It is very good at that and I have no quarrel with your two firms, whose reports I have read twice and one of which I think is the better piece of work. But you have assumed that rock which is removed must go up and out over the top, and that is not how anyone has ever driven an adit in this country. You drive in from the side, you take the spoil out level, and if there is a worked void within a few miles you put it there, because tipping is a cost and a hole is free. You know this. You have written it into your own list of failure modes and then declined to let it disturb your conclusion. > > You checked the subsidence monitoring at Blaenserw and found nothing. I would not expect you to. That drift was monitored twice a year by a man on a motorbike with a level staff, and I knew him. > > Now the thing I actually want said. > > For fifty-one years I and others have written to the ministry, to the county, to two water undertakers and to four members of Parliament, and the answer has always been the same four lines: it is not the department's practice to comment on the location or function of sites of this kind. Not 'there is nothing there'. Not 'it is a reservoir'. The same four lines, for fifty-one years, about a padlocked hatch in a Welsh hillside that your own article says holds nine hundred cubic metres of drinking water. > > If it is a reservoir, why has no one been permitted to say so? > > You will answer that the four lines are a standing form, applied without thought, and you are probably right, and that is precisely the point I have failed to make for fifty years. A state that will not distinguish between a bunker and a water tank has told the valley that both are the same kind of secret. It taught us to read a padlock as a message. Then a television programme arrived with a number, and the valley had already been trained to believe it. > > I was wrong about the size. I was not wrong about the silence, and your paper has now been silent about the silence for nine hundred words. > > One more thing, and then I have finished. You have printed Idris Prydderch's day book and you have printed it well. He was a good man and a rough employer and my uncle drove for him for two years. But I would ask you to notice what you have done with him: you have used a working man's account of three years of dust to close a question, and you have used it because it agrees with you. Had his day book said something else, you would have called it recollection. --- They Buried is a satirical newspaper. Every story, source, document and person in it is invented. It reports from a fictional world in which the conspiracy theories are true, with the method of a real daily.