THRESHOLD COMPLEX EXPLORATION LOG
Designation / Log ID: 46-Q43
Apparent Date/Time: 21 September 2026 / 08:47 (local) — secondary stamp reads 14:22 07 March 1971
Entry Method: Single steel door marked “C-44 CLARIFIER GALLERY – AUTHORIZED PERSONNEL ONLY”. Exterior clear aperture measures 1.98 m × 2.41 m. Interior aperture measures 2.15 m × 2.28 m on entry and 1.87 m × 2.53 m on exit.
Environmental Baseline
Lighting: fluorescent tubes, color temperature measured at 3980 K. Intensity constant at 51 lux.
Ambient temperature: 15.9 °C. Humidity: 67 %.
Background sound: continuous low-frequency clarifier drive resonance at 22 Hz. Baseline reading 21 dB.
Air movement: none detected. Barometric pressure 1013.4 hPa on entry; 1008.1 hPa after 3.8 m of travel.
Spatial Observations
Gallery estimated 68 m long by 8.1 m wide by 4.4 m high. Laser measurement returns 44.2 m long by 7.6 m wide by 3.9 m high.
Floor: sealed concrete with gray chemical-resistant coating. Coating thickness measures 2.3 mm. Surface remains uniform under repeated contact.
Walls: painted concrete block with five vertical clarifier tank arrays. Paint thickness measures 1.0 mm. Surface remains uniform under repeated contact.
Ceiling: exposed structural beams with eleven recessed lamp fixtures. Fixture count remains eleven after fourteen visual inventories.
Repeating motif: every 8.1 m a clarifier tank is mounted against the south wall. Tank height measures 3.22 m. Scraper assemblies are identical across all tanks.
Anomalies
Visual inventory of clarifier tanks returns 5. Physical inventory returns 5. Measured sludge blanket height equals 0.0 m while calculated solids mass across the same tanks equals 24.7 kg.
Floor remains level under spirit level. Measured residual film on the lower wall panels slopes 1.9° toward the west wall. Slope reverses after 5 minutes of continuous observation without change in physical orientation.
Gallery pressure measures 1010 hPa while the external door indicator reads 1015 hPa. Seal integrity lights remain green.
Sound of residual scraper cycle arrives 2.8 seconds after the corresponding surface disturbance is detected. Delay increases by 0.28 s for every additional 1.5 m of distance from the entry door.
Humidity at mid-gallery remains 67 % while residual film forms on the tank housings after 6 minutes of observation. Film disperses without measurable change in local humidity.
Local magnetic field strength measures 0.3 gauss at floor level and 1.9 gauss at 1.8 m height. Field direction reverses after 6 minutes without change in gallery state.
Solids gauge needle count on the status array decreases by 11 over 13 minutes while measured underflow at all transducers remains 0.0 L/min.
Surface of residual film on tank housings exhibits electrostatic cling of 3.8 cm against vertical surfaces. Cling collapses after 37 seconds without measurable change in surface charge.
Entity Notes
None observed.
Exit / Continuity Status
Exit achieved through the same steel door after 47 minutes of observation. Exterior aperture on exit measures 1.87 m × 2.53 m. Residual film on boots dissipates within 9 minutes of exit. Local magnetic field returns to baseline 0.5 gauss within 14 minutes. No further residual effects recorded.