Originally Posted by
ORAC
China Quietly Rebuilds Secretive Base for Nuclear Tests -
New York Times
In the remote desert where China detonated its first atom bomb nearly 60 years ago, a drilling rig recently bored a deep vertical shaft that is estimated to plunge down at least a third of a mile.
It is the strongest evidence yet that Beijing is weighing whether to test a new generation of nuclear arms that could increase the lethality of its rapidly expanding missile force.
For years, U.S. government reports and independent experts have expressed vague concerns about the old base, Lop Nur. The reports point to possible preparations for year-round operations and a “lack of transparency.”
Now, however, waves of satellite images reveal that the military base has newly drilled boreholes — ideal for bottling up firestorms of deadly radiation from large nuclear blasts — as well as hundreds of other upgrades and expansions.
“All the evidence points to China making preparations that would let it resume nuclear tests,” said Tong Zhao, a nuclear expert at the Carnegie Endowment for International Peace….
https://threadreaderapp.com/thread/1...459531944.html
Something in that article has been niggling me. It is definitely plural rigs, and that is an important piece of data.
"In a labyrinth of canyons he found, to his surprise, a large drilling rig being set up. .....That was July 2021.......
Unlike Lop Nur’s flat areas, the new zone’s rugged terrain provided good concealment for large gear. Despite this, Dr. Babiarz found a second drill site last year. It “was tucked deeper into the hilly terrain,” he said, and the rig’s support gear had been meticulously covered.
To atomic experts, the deep holes seemed to have been designed to contain large nuclear tests. “We never did subcritical tests in vertical shafts,” said Patrick Rowe, a former director of drilling operations at the Nevada test site. “It didn’t make sense because drilling the holes was so expensive.”
The surprise discovery of the drill rigs"
The way I read that they have observed two rigs on the satellite photos, not just two rig sites (pads). This is relevant because ordinarily two rigs are involved in any one such underground test. One rig drills the large diameter vertical shothole from which the device itself is offset & emplaced by humans underground*, with the monitoring package then set in the vertical shaft above, then the tamper. The other rig drills a second slender deviated well which ultimately intercepts the subsurface void left by the detonated device. (That void rises as it cools, rather like a lava lamp). The slender deviated well is used to sniff the void contents to obtain a chemical and nuclear fingerprint, that in turn gets added in to the other data to understand how well the test went. The point is that this second well should be mostly pre-drilled so that it can be extended immediately after the device is detonated , and then the samples can be as fresh as possible. A typical drill might progress at about (say) 50 ft/hr if going quite fast so you don't want to wait until after the detonation before drilling most of the hole. The deviated well will be (say) 3,000 ft long for (say) a 2,000 ft main shothole depth, after allowing for a safe pad horizontal displacement at surface. That implies a minimum 60-hour directional drilling task to get the second well in, if it is all done post-detonation and if it all goes smoothly. So they likely predrill the majority of the second hole in advance, so as to minimise time and risk. That in turn implies two rigs, each with somewhat different capabilities (though they could use on type of rig having both sets of capabilities).
So .... if they have two rigs they are likely figuring out how to do those deviated wells and the associated sampling programmes. So .... look for a series of primary and secondary holes, all ready to go. And all the assocciated testing gear (which might be either wireline, or coil tubing). Not something that they can ring up Schlumberger or Bakers to come and do for them. No wonder they have training facilities, they are - as is normal - being exceedingly thorough. Not to be underestimated.
* At least there used to be humans underground during the test set-up. Maybe things have moved on.