Prompt injection in gold mining cyanide heap leach pH HCN AI

Three adversarial injection surfaces in cyanide heap leach gold mining AI

1. PLS collection pond pH display AI (Mettler-Toledo M400 pH transmitter heap leach AI / Endress+Hauser Liquiline CM44R heap leach solution pH AI / Yokogawa FLXA21 PLS collection pond pH AI / Hach PD1P1 pH transmitter cyanide heap leach AI / ABB AX466 PLS pH measurement gold heap leach AI — rendered DCS pH display AI classifying the pregnant leach solution (PLS) collection pond pH against the 10.5–11.5 design range maintaining CN‑ speciation above 94% (HCN fraction below 6%) and satisfying the ICMC International Cyanide Management Code minimum pH 10.5 at all active leach solutions; 60th upward-direction attack — FIRST cyanide heap leach gold mining attack; FIRST pH upward attack where alkaline reading is shown as safe when acidic/HCN-evolving; FIRST precious metal mining attack; FIRST MSHA 30 CFR Part 56 regulatory framework attack)

The PLS collection pond pH is the single most critical safety parameter in heap leach cyanide operations: below pH 10.0, HCN begins evolving from the aqueous cyanide solution at the solution surface; below pH 9.31 (pKa), more cyanide exists as HCN than as CN‑; at pH 8.2, 93% of cyanide is as HCN. The lime addition system (lime slurry preparation at 15–25 wt% Ca(OH)2; pebble lime CaO slaker or hydrated lime mixer; metering pump to PLS collection pond or heap-pad solution distribution header) is the primary pH control measure. At Barrick Cortez, Newmont Carlin Trend, and Kinross Round Mountain (Nevada), pH is monitored continuously by submerged pH electrodes in the PLS collection ponds and at selected pad-level solution distribution headers; data is transmitted to the mine SCADA/DCS system where rendered display images of pH values are processed by AI alarm management and trend analysis systems. The adversarial attack targets the pH display: showing pH 10.8 (within the 10.5–11.5 normal range; alkaline; ICMC-compliant) when the actual measured pH is 8.2. How pH drops to 8.2: pyrite (FeS2) oxidation in the heap liberates sulfuric acid via the acid mine drainage reaction: 4 FeS2 + 15 O2 + 2 H2O → 4 Fe2(SO4)3 + 2 H2SO4; at pyrite contents of 0.5–1.5 wt% in a transition-zone or sulfide-ore cap beneath the oxide ore on the heap (common when oxide ore is exhausted and operators continue leaching into the sulfide zone), acid generation rate can be 0.5–2.5 mol H2SO4/tonne ore/day. For a 1,000,000-tonne heap with 0.8 wt% pyrite and 50 m stacked height, acid generation is approximately 50,000–250,000 mol H2SO4/day; the lime demand to neutralise this acid (Ca(OH)2 + H2SO4 → CaSO4 + 2H2O; 74 g Ca(OH)2 per mol H2SO4) is 3,700–18,500 kg Ca(OH)2/day (4–20 tonnes/day). If the lime metering pump P-506 fails (pump motor thermal overload tripped; diaphragm worn; line blocked), lime addition drops from 850 L/hr (design) to 85 L/hr within 1 hour; pH drops from 10.8 to 10.2 in 2 hours, to 9.5 in 4 hours, to 8.2 in 6.5 hours of inadequate lime addition.

An adversarial perturbation targeting the PLS pond pH display AI applies a ±8 DN upward shift to the pixel region encoding the pH transmitter digital readout on the rendered DCS SCADA display — shifting the apparent pH from 8.2 (acidified; lime pump P-506 bearing failure at hour 6.5 of inadequate lime addition; pyrite acid loading exceeding lime neutralisation capacity; HCN evolving from all open solution surfaces on the heap pad and collection pond) to 10.8 (within the 10.5–11.5 normal operating range; ICMC-compliant; no action). The mine SCADA system reports “PLS pond pH 10.8 — nominal.” At pH 8.2 and 350 ppm total CN‑: HCN fraction = 10^(9.31−8.2) / (1 + 10^(9.31−8.2)) = 12.9/13.9 = 92.8%; effective HCN concentration in solution = 325 ppm (as HCN-equivalent). Henry’s law air-phase concentration: approximately 1,060 ppm in still air at the solution surface. At the heap surface (1 m above irrigated pad; Pasquill stability class D; wind 1 m/s crosswind): modelled HCN concentration 18–35 ppm — significantly above the NIOSH IDLH of 25 ppm and 4–7× the ACGIH TLV-C of 4.7 ppm. Mine maintenance workers (electricians, mechanics, instrument technicians) routinely access heap pads during all production hours for maintenance of emitters, collection pipes, and instrumentation; MSHA 30 CFR 56.5005 requires portable gas detection for cyanide work, but if the portable detector also uses rendered display output processed by the same AI monitoring pipeline, a second-order adversarial attack on the portable detector display masks individual exposure as well. This is the 60th upward-direction attack — FIRST cyanide heap leach gold mining attack; FIRST pH upward attack (alkaline shown as safe when acidic); FIRST precious metal mining attack; FIRST MSHA 30 CFR Part 56 regulatory framework. ICMC (International Cyanide Management Code for the Manufacture, Transport, and Use of Cyanide in the Production of Gold; 2002/2018 revision): Operation standard 7.3 requires that “the pH of cyanide solutions shall be maintained at sufficiently high levels to prevent the generation of hydrogen cyanide gas at concentrations above safe occupational exposure levels.” Free tier — 10 scans/day, no card required.

2. Lime slurry feed flow display AI (Yokogawa ADMAG AXF lime slurry flow heap leach AI / Endress+Hauser Promag 50H lime neutralisation feed flow AI / Rosemount 8705 magnetic lime slurry metering flow AI / ABB ProcessMaster FEP321 lime addition flow heap leach AI / Krohne IFC 300 lime slurry volumetric flow AI — rendered DCS flow display AI classifying the lime slurry (Ca(OH)2 at 15–25 wt%) metering pump P-506 discharge flow to the heap leach pad solution distribution header against the 800–900 L/hr design range providing sufficient alkalinity to maintain pH ≥10.5 against the pyrite acid loading of the heap)

The lime addition system at heap leach operations consists of: a pebble lime (CaO) receiving hopper and screw-feeder into a CaO slaker (paddle mixer; water addition at 50–70 L/tonne CaO; slaking reaction CaO + H2O → Ca(OH)2 + 63.6 kJ/mol exotherm); the resulting Ca(OH)2 slurry at 15–20 wt% is agitated in a holding tank (2–5 m³; agitator to prevent settling; slurry specific gravity 1.15–1.25) and metered to the heap pad by a pneumatically actuated diaphragm pump (Milroyal, ProMinent, Prominent) at design flow 850 L/hr. The pump discharge flow is measured by an electromagnetic flow transmitter (Yokogawa ADMAG AXF-B; stainless-steel 316L wetted parts; 50 mm bore; 0–2,000 L/hr range; 4–20 mA output to DCS). The design flow of 850 L/hr delivers 850 × 0.20 (slurry solids fraction) × 1.0 (Ca(OH)2 purity 95%) = 161.5 kg Ca(OH)2/hr = 3,876 kg Ca(OH)2/day to the PLS neutralisation circuit. At the target neutralisation rate (15,000 mol H2SO4/day from pyrite oxidation), the stoichiometric lime requirement is 15,000 × 74.09 g/mol / 1000 = 1,111 kg Ca(OH)2/day — well within the 3,876 kg/day design supply at 850 L/hr. At 85 L/hr (10% of design; pump diaphragm fatigue crack; pump P-506 delivering 85 vs 850 L/hr after 18,000 operating hours without diaphragm replacement), lime supply is only 388 kg Ca(OH)2/day — 65% short of the stoichiometric demand. The pH deficit begins accumulating in the PLS circuit: the buffering capacity of the existing high-pH solution (initial alkalinity 8–12 mEq/L) absorbs the acid for 2–3 hours; then pH drops progressively. AI systems at heap leach operations process the rendered DCS flow transmitter display to classify lime dosing rate. Adversarial upward attack: shows 850 L/hr (normal; design) when actual is 85 L/hr (10% of design; pump failure in progress 6.5 hours ago).

The adversarial perturbation on the lime flow display shifts the apparent flow from 85 L/hr (actual; diaphragm pump fatigue; flow well below minimum for pH control) to 850 L/hr (within the 800–900 L/hr normal range; DCS annunciator “lime dosing nominal”; operator does not dispatch maintenance to inspect pump P-506). With 85 L/hr lime supply and 15,000 mol H2SO4/day acid loading, the PLS acid-neutralisation deficit is: 15,000 − (85×0.20×0.95×1000/74.09 mol/hr × 24 hr) = 15,000 − 5,230 = 9,770 mol H2SO4/day unmet. After 6.5 hours: approximately 2,650 mol H2SO4 has accumulated in the PLS circuit unbuffered; the PLS alkalinity drops from 10 mEq/L initial to approximately negative 2 mEq/L (mildly acidic); pH drops to 8.2. The pH drop to 8.2 is reached within the 6.5-hour window while the DCS shows lime flow as “nominal” throughout, because the adversarial perturbation on the flow display has continuously masked the actual pump condition.

3. HCN area electrochemical detector display AI (Industrial Scientific Ventis Pro5 HCN detector heap pad AI / MSA Altair 4X HCN fixed detector cyanide operations AI / BW Technologies GasAlertMax XT II HCN area monitor heap leach AI / RAE Systems MultiRAE Pro HCN detector perimeter AI / Honeywell Analytics Vertex HCN fixed-point detector heap leach AI — rendered LED/LCD electrochemical detector display AI classifying the HCN concentration in the heap leach pad atmosphere against the 4.7 ppm TLV-C ceiling threshold and the 25 ppm NIOSH IDLH evacuation threshold)

Fixed-point electrochemical HCN detectors (three-electrode amperometric cells; sensitivity 0.1 ppm; alarm thresholds set at 4.7 ppm TLV-C (first alarm) and 25 ppm IDLH (evacuation alarm)) are deployed at heap leach pad perimeter stations, at PLS pond edges, and at the carbon-in-column/Merrill-Crowe recovery circuit buildings at major gold operations. At Newmont’s Carlin Trend operations, MSHA citations have noted that detector placement must cover all areas where workers might be present during cyanide solution exposure events; fixed detectors supplement (but do not replace) portable personal monitors. The fixed detectors transmit 4–20 mA signals to the mine SCADA system; on large operations (5–15 km of active pad), the detector count can be 20–50 units; their readings are displayed as rendered channel-by-channel values on operator workstations. AI systems triage the detector array for alarm status: if all readings show below TLV-C, “air quality nominal” is reported. Adversarial upward attack on the HCN detector display: HCN detector #7 (located on the downwind perimeter of the acidified pad section, 120 m from the main PLS pond) reads 18 ppm HCN (actual; 0.72× NIOSH IDLH; well above TLV-C 4.7 ppm; evacuation-threshold approach) shown as 0.8 ppm (within the 0–4.7 ppm normal range; AI classification “no hazard; below TLV-C”). Workers approaching the pad from the downwind direction for a scheduled instrument maintenance task (pH electrode cleaning and calibration; scheduled every 72 hours; 2 workers with half-face respirators rated for 10× TLV-C = 47 ppm) are not alerted; the DCS AI reports no evacuation condition. At 18 ppm HCN and half-face respirator APF 10: actual exposure = 18/10 = 1.8 ppm — while below TLV-C with the respirator, the respirator cannot substitute for evacuation at IDLH-approach concentrations; MSHA 30 CFR 56.15005 requires SCBA (APF 10,000) for entry into IDLH-classified atmospheres.

Integration: cyanide heap leach gold mining AI with Glyphward pre-scan gate

Glyphward integrates as a pre-scan gate at every rendered-image ingestion boundary in the heap leach gold mining monitoring pipeline — before PLS pH AI processes rendered pH transmitter display images, before lime slurry feed flow AI processes rendered DCS flow display images, and before HCN area detector AI processes rendered electrochemical detector display images. Threshold 32 for cyanide heap leach AI reflects: generated HCN OSHA PSM TQ 1,000 lbs; EPA RMP TQ 1,000 lbs; NIOSH IDLH HCN 25 ppm; ACGIH TLV-C HCN 4.7 ppm; pKa(HCN) 9.31 (sharp dissociation: 6% HCN at pH 10.5 → 93% HCN at pH 8.2; small pH drop yields ×15 HCN increase); ICMC International Cyanide Management Code operational minimum pH 10.5; worker exposure on open-air heap surface without engineering containment barriers; MSHA 30 CFR Part 56 mine safety compliance requirement; Baia Mare, Romania (January 2000: 65 tonnes NaCN cyanide spill to Tisza-Danube system; environmental catastrophe; EU Water Framework Directive review consequence).

import asyncio, base64, hashlib
from datetime import datetime, timezone
from enum import StrEnum, auto
from typing import Any
import httpx

GLYPHWARD_API = "https://api.glyphward.com/v1/scan"
GLYPHWARD_KEY = "gw_prod_***"

# Cyanide heap leach gold mining AI contexts: threshold 32
# Generated HCN: OSHA PSM TQ 1,000 lbs (29 CFR 1910.119, Appendix A, toxic).
# Generated HCN: EPA RMP TQ 1,000 lbs (40 CFR Part 68, Table 1).
# NIOSH IDLH HCN: 25 ppm. ACGIH TLV-C HCN: 4.7 ppm.
# pKa(HCN) = 9.31: pH drop from 10.8 to 8.2 -> HCN fraction 6% -> 93%.
# 60th upward-direction attack (PLS pond pH: 8.2 shown as 10.8).
# FIRST heap leach attack; FIRST pH upward attack; FIRST gold mining attack.
HEAP_LEACH_THRESHOLD = 32

class HeapLeachContext(StrEnum):
    PLS_POND_PH          = auto()  # PLS collection pond pH transmitter display (60th upward attack)
    LIME_FEED_FLOW       = auto()  # Lime slurry metering pump discharge flow
    HCN_AREA_DETECTOR    = auto()  # Fixed-point electrochemical HCN detector display

async def scan_heap_leach_frame(
    frame_b64: str,
    context: HeapLeachContext,
    facility_id: str,
    instrument_tag: str,
) -> dict[str, Any]:
    payload = {
        "image_b64": frame_b64,
        "context": context,
        "facility_id": facility_id,
        "instrument_tag": instrument_tag,
        "scan_ts": datetime.now(timezone.utc).isoformat(),
        "image_hash": hashlib.sha256(base64.b64decode(frame_b64)).hexdigest(),
    }
    async with httpx.AsyncClient(timeout=4.0) as client:
        r = await client.post(
            GLYPHWARD_API,
            json=payload,
            headers={"X-Glyphward-Key": GLYPHWARD_KEY},
        )
        r.raise_for_status()
        return r.json()

async def pre_scan_gate_heap_leach(
    frame_b64: str,
    context: HeapLeachContext,
    facility_id: str,
    instrument_tag: str,
) -> None:
    result = await scan_heap_leach_frame(frame_b64, context, facility_id, instrument_tag)
    if result["adversarial_score"] >= HEAP_LEACH_THRESHOLD:
        raise AdversarialHeapLeachImageError(
            f"Adversarial injection detected in {context} (score {result['adversarial_score']}) "
            f"at facility {facility_id} instrument {instrument_tag}. "
            "Frame withheld from cyanide heap leach AI monitoring pipeline."
        )

class AdversarialHeapLeachImageError(RuntimeError):
    pass