The piles are in. Proving they'll hold is the part that's left.
All 155 piles were installed by Oct 2, and Cantsink's engineer has certified them. Every one passed the twisting test. The soil borings found a weak layer that the twisting test can't see, so a pass doesn't settle it.
What was built
Each pile is a steel screw. A machine turns it into the ground until the twisting force (torque) reaches a target. The harder it is to turn, the more weight it should carry. Cantsink's engineer, Dr. Souissi, signed a letter on Oct 5 saying every pile met its load.
Two pieces of evidence came in since then. Andrew Carter answered our questions today (Oct 6, 1:57 pm). The soil borings from Oct 5 show what the piles are actually sitting in.
What the borings found: a firm crust over a loose layer
On Oct 5, Quartet's driller bored two holes (B-1 and B-2) and counted hammer blows every few feet. More blows means firmer soil. Both holes show the same pattern: a firm layer around 18–21 ft, then a loose, wet layer at 23–26 ft (only 1–2 blows to start), then dense sand from about 28 ft.
This layer isn't new. Quartet's own 2025 borings logged the same "loose silty sand" at 23–25 ft. That's probably why their report set a 20-ft minimum depth.
| Depth | B-1 (Oct 5) | B-2 (Oct 5) | 2025 borings | What it means |
|---|---|---|---|---|
| 4–12 ft | organic silt 6–12 ft, bad smell, N 6–8 | sandy clay, N 8–18 | N 11–15 | Soft. Organic soil can corrode steel. |
| 13–15 ft | N 12 | N 8 | N 18–23 | Where the twelve 14-ft piles stop |
| 18–20 ft | N 23 | N 27 | N 18–20 | firm crust Most piles stop here |
| 23–25 ft | 1-1-9 (N 10) | 2-1-10 (N 11) | N 8, 9, 12 | loose Below the water table |
| 28–30 ft | N 33 | N 42 | B-3: N 15 to 40 ft | dense here, not everywhere |
N = hammer blows to drive the sampler 12 inches. Under ~10 is loose; 30+ is dense. These are the driller's handwritten field logs. Quartet's lab report hasn't arrived. The 2025 rig used an automatic hammer and the 2026 rig a manual one, so the numbers are close but not exactly comparable.
Why passing the twisting test doesn't settle it
Torque only measures how hard the soil right at the screw blade resisted turning. But a loaded blade pushes on soil 2–3 blade-widths below it, about 2–3½ ft for these 12–14″ blades. A pile that stops on the firm crust at 20 ft is pressing into the loose layer a few feet down. It can show full torque on the gauge and still settle more than expected.
We've already seen this once. In front of witnesses on 9/28, pile 12 was given a second turn after it passed. It sank through, and its torque dropped to about 2,300 below 26 ft.
The dashed outline is the soil the blade loads. Only a load test, which pushes on a pile and measures how far it sinks, can tell whether the crust is thick enough.
| Where the blade stops | Piles | Risk | Which piles |
|---|---|---|---|
| 14–17 ft (above the crust) | 30 | soft soil | Twelve at 14 ft: 18, 19, 21, 22, 23, 28, 122, 125, 126, 136, 137, 139 |
| 18–22 ft (on the crust) | 78 | loose layer 1–5 ft below | Most of the house. Dmitri's list: 46, 41, 42, 37, 71, 101, 104, 105 |
| 23–25 ft (in the loose layer) | 21 | highest | 1, 2, 5, 7, 9, 13, 14, 39, 43, 44, 45, 50, 52, 79, 87, 88, 89, 96, 131, 150, 152 |
| 26–27 ft (bottom edge) | 5 | lower | 11, 31, 138, 142, 143 |
| 28 ft and deeper | 21 | lowest | 4, 6, 8, 10, 12, 17, 27, 30, 58, 59, 61, 63, 80, 83, 92, 97, 116, 124, 127, 146, 154 |
"Net" depth = installed length minus what was cut off above ground. Cantsink writes "24′-3" meaning 24 ft installed, 3 ft cut off, so 21 ft in the ground. It isn't 24 ft 3 in. Dmitri's risk report read it the second way, so several of his depths are 3–4 ft too deep.
What Cantsink said today
Andrew Carter answered our seven questions at 1:57 pm. Juan, Scott, Dmitri, Murat and Yasamin were copied, plus Brittany and Sara Hayes. His answers, and whether each one holds up:
| We asked | Andrew said | Verdict |
|---|---|---|
| Recorded torque data | The monitor can record every 2 seconds, but they don't turn it on. A printout after the fact is "not possible." | gone No independent record exists. The handwritten logs are all there is. |
| Original field sheets | "We will collect the field logs and send them over." | promised Hold him to a date |
| Pile 17 (erased 2,717) | Pulled out completely; a 10″ blade replaced with 12″ around 9/28–29. | plausible Field sheet should show it |
| 19 "No Cut" notes rewritten | A misunderstanding with the crew leader, fixed in the final logs. He explained what each note means. | partly Field sheets will confirm |
| Pile 46 (7,003 vs video) | The number on screen changes every second; both are above 60,000 lb. | fair 7,096 is above the shaft rating, though |
| Pile 87 (6,618) | It's half of a pair that shares 100,000 lb, so it needs only 5,556. "Needs no further work." | resolved If Juan confirms 87/88 is a pair |
| The 9/24 10:47 am N·m pile | "I'm not aware of the pile you are referring to." All piles were finished in ft-lb. | unanswered Murat can identify it from the video |
| Burned bolt holes | "Noted on the final logs." | not answered The logs record no burned holes |
| Which piles are pairs | Listed all 22 pairs. 128/129 and 130/131 were doubled by mistake from staking, at no charge. | answered |
Andrew also says the piles' combined capacity beats the design total by about 500,000 lb. A house doesn't share load that way, though. Each pile carries the column or wall above it, so each one has to pass on its own.
Every pile passed its torque target, by a thin margin
Every final reading is above its target. But most are only a few percent over, and 46 are above what the shaft is rated to take (7,091). The couplings are the weak point; pile 145's coupling broke above 8,500.
Final torque in ft-lb, in 50 ft-lb steps. Single piles need 6,667; piles in a pair need 5,556. The only reading under 6,667 is pile 87, which is half of a pair. The monitor is accurate to about ±80 ft-lb.
What the paperwork still doesn't show
Settled
- Units: the tablet switched to ft-lb on 9/24, between 10:47 am and 3:33 pm, and every final reading is in ft-lb.
- Calibration: every tablet screen shows serial 638000EC (calibrated June 1, 2026), and RockSolid photographed the same number stamped on the rig.
- RockSolid's 67 photographed readings: 47 match the final log, 20 are earlier readings that were later redone, none conflict.
- Murat's own photos of the tablet match the final logs (one pile is off by 1).
- Pile 87: covered as half of a pair, pending Juan.
Still open
- Only 2 of 155 final readings were witnessed by the inspector: piles 110 and 111 on 9/26 (6,857.9 and 6,839.7, matching the log). Every other entry on RockSolid's forms is copied from Cantsink.
- No raw data exists; the field sheets are promised.
- Burned bolt holes appear in RockSolid's own 9/26 photo (three torch-cut holes in a cut shaft) and in Murat's photos, but not in the logs.
- First attempts left off the final log: the original 10″ piles 110 and 111 (about 5,550 ft-lb before the units were fixed), 93, 94, 95 and the early pile 80. Pile 145's sheet says "snapped lead."
- The N·m pile from 9/24 10:47 am is unidentified.
- Piles 109 and 125 first appear on the final log.
- Pile 12's original test isn't in the log.
What this could cost
| Item | Amount | Basis |
|---|---|---|
| Cantsink base (via Keystone) | $86,700 | Proposal: piles to 17 ft |
| Depth over 17 ft, if billed | $23,058 – $33,684 | $28/ft × 824 ft (net depth) to 1,203 ft (installed length). Only through a signed change order (Keystone addendum §7). |
| Two extra piles (128–131) | $0 | Andrew: "will not be charged to anyone" |
| Load test on 2–3 piles | quote pending | Quartet hasn't quoted yet |
Range only. Which depth Cantsink bills on (installed length or depth in the ground) isn't settled, and nothing has been invoiced.
So what do you do?
The next tab lays out the steps in order, with who owns each one and what has to be true before concrete is poured.
10 · What To Do