Jackie Vs. AI uses the Yellow Springs as a deep, almost geological reference. Zhang_guolao, the oldest of the Council, riding his donkey backward, refers to himself in Ch6 as having drunk from the Yellow Springs and come back up before the courts were built. It is one of the book's quietest mythological jokes: the joke that the bureaucracy of death is itself a relatively recent imposition on a much older arrangement.
The Springs return as imagery in Ch13 (gong_gong_rises), when the chapter describes the methodology's pressure as something coming from beneath — not from the courts of Diyu, with their registers and their judges, but from the older place, the subterranean water that simply takes the dead and holds them. The book uses the older underworld to mark a horror that is below judgment, below paperwork — the horror of being absorbed rather than processed. Anna's nine floors underground are described, once, as nine floors toward the Yellow Springs.
Huang Quan is one of the oldest concepts in Chinese cosmography. The phrase appears in Shang and Zhou oracle bones, and the most famous classical reference is in the Zuo Zhuan (4th c. BCE), in the story of Duke Zhuang of Zheng, who swore not to see his mother again until they met at the Yellow Springs — a vow he later evaded by digging a tunnel deep enough to qualify. The Springs are described as a still, dark, subterranean realm: yellow because the soil and water of the North China Plain are yellow, springs because that is where the dead are (water beneath earth).
The Yellow Springs predate Buddhist underworld imagery and exist in earlier Chinese cosmography without judges, demons, or rebirth machinery. With the Tang-dynasty importation of Buddhist Naraka cosmology, the older Springs were largely supplanted by the more elaborate diyu — though the phrase survived in poetry and in everyday euphemism for death.
Death as down. The Springs are pre-bureaucratic: death is simply being beneath, not being judged. The books use this as the quieter, older horror.
Yellow because of the soil. The name is geological — the North China Plain's loess colors its springs yellow. Cosmography here grew out of physical geography.
Below judgment. Where diyu is paperwork, the Yellow Springs are absorption. The Chronicles treat this as the deeper threat: not being processed, but being held.
Anna's nine floors. The books describe Anna's underground confinement as toward the Yellow Springs — a child being lowered into the older underworld, not the bureaucratic one.