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Mining/
Specialized fields/
Placer and alluvial miningPlacer and alluvial mining, measured downstream.
Placer gold, tin and gem gravels are worked in rivers and floodplains, often far from power and networks and often by small and artisanal operators. What matters is what leaves the site: sediment and turbidity in the river, sometimes mercury, the stability of settling ponds and the land handed back. Solar stations, LoRaWAN and satellite links make all of it measurable and shareable.
Plan a deploymentHow it worksStation Builder- Industry
- Mining
- Measurements
- 6
- Sources cited
- 6
Mining · Placer and alluvial mining
A river that carries the evidence
Placer mining washes gravel with river water and returns it, so the river carries the evidence of how a site is run. Many workings are small, remote and informal, and the people downstream live with the result. Measuring what leaves the site, openly, is the foundation of a licence to operate and of responsible sourcing.
What is measured
Sediment, level, chemistry and rain
Sondes measure turbidity, pH, conductivity and temperature upstream and downstream of the workings and at pond outlets. Level sensors gauge the river and the spillways, a rain gauge watches the catchment, and laboratory samples for mercury are taken where and when the continuous record shows they matter.
- Instruments
- Water-quality sondes · Level sensors · Rain gauge · Laboratory samples
The base node
Stations that need no grid
Each station is a sonde and a level sensor read by a battery LPWAN endpoint, with a small solar panel. The endpoint stamps and sends short readings to the gateway, which checks them against the upstream reference, signs them and keeps a local copy until the backhaul confirms delivery.
Radio and links
LoRaWAN up the valley, satellite out
One LoRaWAN gateway on high ground hears stations along the reach. Where a public network reaches the valley, a cellular modem carries the data; where none does, a LEO or satellite IoT terminal does. The choice comes from the survey, and the stations do not change if the backhaul does.
- Radio
- LoRaWAN · Satellite · Public cellular
How it works
From a sonde to a shared record
A sonde reports over SDI-12 to its endpoint, the endpoint sends over LoRaWAN to the gateway, and the gateway forwards over satellite to the governed record. There, each reading is compared with the upstream station, flagged for quality and published to the operator, the agency and, where agreed, the community.
From order to operation · Order
Scope the reach and the permit
The scope starts with the river: where the workings are, where the reference and compliance points must be, what the permit or the community agreement requires and whether mercury is part of the story. Nexus Observatory Inc. returns a station plan, the radio approach, the sampling programme and a price per reach.
Plan a deploymentFrom order to operation · Survey
Walk the river with the people who use it
The crew walks the reach with the operator and, where agreed, with community monitors. It chooses stable sections for sondes and gauges, checks flood marks, finds high ground for the gateway, measures radio coverage and records every position with photos, coordinates and the landholder’s consent.
From order to operation · Permits
Water, land and community agreements
Stations in a river need the consent of the landholder and, often, of the water authority. Discharge monitoring follows the operator’s permit, and mercury sampling follows the national plan where one exists. Agreements say who may see which data before any station is installed.
From order to operation · Build
Build stations that survive floods
Sondes, level sensors and endpoints are assembled with their solar panels and batteries, configured and tested on the bench, then enrolled with their identities. Mounts are chosen for scour and debris, and every part is labelled so a local technician can swap it in the field.
Open the Station BuilderFrom order to operation · Install
Install in a low-water window
Installation is planned for low water. The gateway and its backhaul go in first, then the upstream reference, the downstream compliance stations, pond outlets and the rain gauge. Every station is levelled to a benchmark and photographed for the record.
From order to operation · Commission
Commission against samples
Each station proves its identity, then its readings are compared with grab samples analysed by a laboratory and with a manual level reading. Alarm levels for turbidity come from the permit or the agreement, and a test alarm runs from the river to the operator’s phone.
From order to operation · Operate
See the plume as it forms
The console shows each station against the upstream reference, so a plume from a wash plant or a breached pond is visible as it forms. Alarms reach the operator and, where agreed, the agency and the community, with the data and the location attached.
From order to operation · Maintain
Clean, calibrate and train locally
Sondes foul in sediment-laden water, so cleaning and calibration follow a schedule driven by the data itself. Local technicians and community monitors are trained to do routine visits, and every visit updates the record that the next person works from.
Book field servicesData products
One river, several readers
Operators see their discharge against the upstream reference and their permit; water authorities receive compliance series in their own system; communities see the agreed stations in their language; health agencies receive mercury results with their chain of custody. Rehabilitation maps show the land handed back, season by season.
See the data productsEvidence
Evidence for permits and responsible sourcing
Station positions, calibrations, laboratory results and every alarm are kept as signed records. Discharge monitoring follows the operator’s permit, mercury work follows the Minamata Convention’s approach for artisanal gold, and data moves through OGC standards, so a buyer, an agency or a community can verify it independently.
- Drawn against
- Minamata Convention · 40 CFR Part 440 · WMO-No. 168
What you get
Environmental and permit monitoring
Emissions, water quality, noise and dust monitoring for permit conditions, with traceable calibration and evidence bundles. Delivered as managed service and data licence, for industrial operators, municipalities, regulators. Scale: Site to portfolio. Service levels are written as numbers you can measure on your own dashboard.
Talk to salesNext step
Plan placer and alluvial mining with us
Tell us the site, the measurements and the rules it answers to. We reply with a survey proposal, a design and a scope for placer and alluvial mining. An engineer replies with a survey proposal and a scope, and the plan grows from one site to the network you need, at your pace.
Plan a deploymentOpen the Station BuilderOpen the Studio
01The place and its hazards
Where it runs, and what can go wrong.
Operating contextPlacer deposits concentrate heavy minerals in river gravels, terraces and floodplains. Operations range from dredges and excavator-and-wash-plant sites to small and artisanal workings. Water washes the gravel and returns to the river, so sediment and turbidity are the defining environmental measurements, and where mercury is used to amalgamate gold its release threatens people and rivers far downstream.
Hazards
- Turbidity and sediment plumes downstream of wash plants
- Mercury release where amalgamation is used
- Failure of settling ponds and small dams in floods
- Collapse of riverbanks and pit walls in loose gravels
- Flash floods reaching workings in the channel
02What must be measured
What, where, how often, and under which rules.
Each measurement names where it is taken, how often, and the public standard or regulation behind it. Numbers in the sources column open the cited source below.
| Measurement | Where | Cadence | Sources |
|---|---|---|---|
| Turbidity and suspended sediment | Upstream and downstream of the workings, and at pond outlets | Continuous | 12 |
| River level and flow | Gauging points on the reach and pond spillways | Continuous | 3 |
| Mercury in water and sediment | Downstream reaches and community water points | Laboratory samples on a schedule, guided by the continuous record | 4 |
| pH, conductivity and temperature | With turbidity at every water station | Continuous | 3 |
| Rainfall | In the catchment upstream of the workings | Continuous | 5 |
| Land disturbance and rehabilitation | The whole lease, from satellite and drone imagery | Each new image, at least every season | 6 |
03The observation stack
From one base unit to a network.
The same blocks at every scale: instruments and a base node, a site with its radio, a fleet run as one, and a network federated on the open protocol.
- 01
Base unit
A solar water station: a sonde and a level sensor read by a battery LPWAN endpoint, or a small node with a satellite modem where no gateway reaches.
Build a station → - 02
Site
A reach of river: an upstream reference station, downstream compliance stations, pond outlets and a rain gauge, with a LoRaWAN gateway on high ground.
Plan a site → - 03
Fleet
Every lease and wash plant of an operator, or every operator in a district, measured the same way so that results compare.
Managed offers → - 04
Network
Catchment agencies, operators and communities share one record of the river, each with the access their agreement gives them.
The open protocol →
- 01Water quality sonde
- 02Water level gauge
- 03Compact weather station
- 04LPWAN endpoint
- 05LoRaWAN gateway
- 06LEO flat-panel terminal
- 07Solar array
- 08Pole
Radio and links
LoRaWAN
Small readings from many river points travel a long way to one gateway on a hill, from stations that run on batteries and small solar panels.
Radio and links
Satellite
LEO broadband or satellite IoT carries the gateway’s data where there is no cellular network in the valley.
Radio and links
Public cellular
Where a public network reaches the river, a cellular modem is the simplest backhaul.
Edge computeA small node at the gateway checks every reading against its upstream reference, flags plumes as they form and keeps a local copy, so a lost satellite pass never loses data.
PowerEvery station runs on solar and batteries sized for the cloudiest season; the gateway shares a solar skid on high ground, out of reach of floods.
04How it works
From the instrument to the product.
One observation’s path, tier by tier, with the interface on every link and a bill of materials below; then how the one node grows to a site, a fleet and federated networks.
Placer and alluvial mining: data path
– of 07
01 Instruments Measurement with sensor identity andcalibration 02 Field radio 03 Gateway 04 Backhaul 05 Site Consumer inbox deduplicates and applieseach record once into governed data 06 Data store Governed product through API, map orexport, correction-aware 07 Products OGC SensorThings APILoRaWANWaterML 2.0 08 Power and structure Supplies 12 V DC, 48 V DC to the fieldequipment 01 Water quality sonde SDI-12 · RS-485 · Ethernet 02 Water level gauge SDI-12 · RS-485 · Ethernet 03 Compact weather station SDI-12 · RS-485 · Ethernet 04 LPWAN endpoint Analogue I/O · SDI-12 · RS-485 05 LoRaWAN gateway Ethernet · RF · GNSS antenna 06 LEO flat-panel terminal Ethernet Site MQTT 5 with Sparkplug B Governed data store Versioned, correction-aware Turbidity and sedimentrecord against the upstreamreference Discharge compliancereports River level and flood alerts Mercury sampling resultswith their chain of custody Disturbance andrehabilitation maps 07 Solar array RS-485 08 Pole SDI-12 SDI-12 RS-485 LoRaWAN Ethernet Satellite IP| Item | Equipment | Data ports | Protocols | Power in |
|---|---|---|---|---|
| 01 | Water quality sondeMulti-parameter sonde for temperature, conductivity, pH, dissolved oxygen and turbidity. | SDI-12RS-485Ethernet | SDI-12, Modbus, MQTT 5, OGC SensorThings API | 12 V DC |
| 02 | Water level gaugeRadar, pressure or float gauge for river, lake, reservoir or tide level. | SDI-12RS-485Ethernet | SDI-12, Modbus, MQTT 5, OGC SensorThings API | 12 V DC |
| 03 | Compact weather stationAll-in-one or compact station for temperature, humidity, pressure, wind and rain at a site. | SDI-12RS-485Ethernet | SDI-12, Modbus, MQTT 5, OGC SensorThings API | 12 V DC |
| 04 | LPWAN endpointBattery-powered endpoint on LoRaWAN, NB-IoT or LTE-M that carries one or more sensors. | Analogue I/OSDI-12RS-485 | LoRaWAN, OMA LwM2M, CoAP | Internal battery, Energy harvesting |
| 05 | LoRaWAN gatewayMulti-channel LoRaWAN gateway that forwards uplinks to a network server and schedules downlinks within duty limits. | EthernetRFGNSS antenna | LoRaWAN, MQTT 5 | PoE, 12 V DC |
| 06 | LEO flat-panel terminalElectronically steered flat-panel user terminal for low-Earth-orbit broadband constellations. | Ethernet | — | PoE, 48 V DC, AC mains |
| 07 | Solar arrayPV modules with charge controller sized to the site’s load and climate. | RS-485 | Modbus | — |
| 08 | PoleUtility, street or dedicated pole with clamp positions. | — | — | — |
How it scales
01 Instruments Arbitrary qualified sensors and instruments whosemeasurements are ingested with calibration, units,geometry, time, custody and uncertainty. ×n 02 Node The minimum useful deployable unit: server, ruggedappliance, radio node, sensor gateway, satelliteterminal, AI, scientific, vehicle or virtual node. Node Node agent 03 Site The minimum independently operable localgovernance and failure domain: one or more nodesplus local network, identity, policy, evidence,storage, products and operator surfaces.SITE
Node Node Node ×n 04 Cluster An optional scale or specialisation domain forscheduling, shared storage, accelerators or datalocality.CLUSTER
×n 05 Fleet Coordinates plans, acknowledgements,convergence evidence, update campaigns andcorrection propagation across nodes and sites.FLEET
Fleet controller ×n 06 Federation An exchange of products, capabilities, events orwork across approved, independently administeredtrust domains, using explicit trust, policy,data-locality, version and correction contracts.TRUST DOMAIN
TRUST DOMAIN
TRUST DOMAIN
×n Verifier Applications Data in the field Telemetry Control Data upstream Control Data upstream Control Exchange Evidence Events Exchange- Data in the field
- MQTT 5 with Sparkplug B; connectors for LoRaWAN, OPC UA and instrument buses.
- Telemetry
- OpenTelemetry OTLP.
- Control
- TLS 1.3 with mutual authentication; protobuf messages over gRPC or HTTP/2.
- Data upstream
- At-least-once publication with repeat-safe keys over the control channel or NATS JetStream; QUIC MAY be used on lossy links.
- Evidence
- DSSE-signed in-toto statements; SLSA provenance; SCITT transparency receipts.
- Events
- Event envelopes mapped to CloudEvents 1.0; channels described in AsyncAPI 3.
- Exchange
- OpenAPI 3.1; the OGC API family; SensorThings; STAC; WIS 2.0.
05From order to operation
Every step, from the first call to a running site.
The same crew and the same record carry the work from scope to maintenance.
- 01 Order
Scope the reach and the permit
The scope starts with the river: where the workings are, where the reference and compliance points must be, what the permit or the community agreement requires and whether mercury is part of the story. Nexus Observatory Inc. returns a station plan, the radio approach, the sampling programme and a price per reach.
- 02 Survey
Walk the river with the people who use it
The crew walks the reach with the operator and, where agreed, with community monitors. It chooses stable sections for sondes and gauges, checks flood marks, finds high ground for the gateway, measures radio coverage and records every position with photos, coordinates and the landholder’s consent.
- 03 Permits
Water, land and community agreements
Stations in a river need the consent of the landholder and, often, of the water authority. Discharge monitoring follows the operator’s permit, and mercury sampling follows the national plan where one exists. Agreements say who may see which data before any station is installed. 24
- 04 Build
Build stations that survive floods
Sondes, level sensors and endpoints are assembled with their solar panels and batteries, configured and tested on the bench, then enrolled with their identities. Mounts are chosen for scour and debris, and every part is labelled so a local technician can swap it in the field.
- 05 Install
Install in a low-water window
Installation is planned for low water. The gateway and its backhaul go in first, then the upstream reference, the downstream compliance stations, pond outlets and the rain gauge. Every station is levelled to a benchmark and photographed for the record.
- 06 Commission
Commission against samples
Each station proves its identity, then its readings are compared with grab samples analysed by a laboratory and with a manual level reading. Alarm levels for turbidity come from the permit or the agreement, and a test alarm runs from the river to the operator’s phone.
- 07 Operate
See the plume as it forms
The console shows each station against the upstream reference, so a plume from a wash plant or a breached pond is visible as it forms. Alarms reach the operator and, where agreed, the agency and the community, with the data and the location attached.
- 08 Maintain
Clean, calibrate and train locally
Sondes foul in sediment-laden water, so cleaning and calibration follow a schedule driven by the data itself. Local technicians and community monitors are trained to do routine visits, and every visit updates the record that the next person works from.
06Data products and integration
What it delivers, to whom, and into which systems.
Data products
- Turbidity and sediment record against the upstream referenceOperators, water authorities, communities
- Discharge compliance reportsEnvironmental managers and regulators
- River level and flood alertsSite supervisors and downstream communities
- Mercury sampling results with their chain of custodyHealth and environmental agencies
- Disturbance and rehabilitation mapsLease holders, land agencies, rehabilitation funds
Integration
- Agency water information systemsSeries are exchanged through OGC SensorThings and the formats the agency’s hydrometric system accepts.
- Community dashboardsAn open view of agreed stations is published for downstream communities, in their language.
- GIS and lease recordsDisturbance maps are delivered as georeferenced layers alongside the lease boundaries.
Exchanged through OGC SensorThings API, LoRaWAN, WaterML 2.0.
07Questions buyers ask
Before you scope it.
Can small operators afford this?
Stations are compact and solar powered, and a district can share one gateway and one service. Programmes are often funded by agencies or buyers who want verified responsible sourcing.
Can communities take part?
Yes. Community monitors can host and read stations and see the agreed data. Their readings carry the same metadata and quality flags as every other source.
Do sensors measure mercury directly?
No. Mercury is measured from samples in a laboratory. The continuous record shows when and where to sample, and the results join the same record with their chain of custody.
What happens in a flood?
Stations and the gateway are sited and mounted for flood flows, and every station stores its data until the link returns.
08Resources
The sources behind this page.
Public standards, regulations and guidance, cited where they apply. Each applies only where its jurisdiction or scope does.
- 140 CFR Part 440: Ore mining and dressing point source categoryUS Environmental Protection Agency (eCFR)
- 2National Pollutant Discharge Elimination System (NPDES)US Environmental Protection Agency
- 3Guide to Hydrological Practices (WMO-No. 168)World Meteorological Organization
- 4Minamata Convention on Mercury (Article 7, artisanal and small-scale gold mining)United Nations Environment Programme
- 5Guide to Instruments and Methods of Observation (WMO-No. 8)World Meteorological Organization
- 6Copernicus Sentinel-2 optical missionEuropean Space Agency
09Related
Use cases and solutions.
Use caseLow-cost stream gauge network
Radar or pressure level sensors with low-power radio and solar power, as a cheaper tier beside a national gauge network.The full use case →SolutionEnvironmental and permit monitoring
Emissions, water quality, noise and dust monitoring for permit conditions, with traceable calibration and evidence bundles.Solutions for mining →SolutionHydrometeorological and flood observing networks
Stream gauges, rain gauges, weather radar and automatic weather stations built to WMO practice, reporting through WIS 2.0 where the agency requires it.Solutions for mining →SolutionSatellite and non-terrestrial backhaul
LEO and GEO backhaul, 3GPP non-terrestrial integration and direct-to-device fallbacks for remote sites.Solutions for mining →10Mining: specialized fields
Other fields of this industry.
Specialized fieldOpen-pit mining
Slope radar, prisms and GNSS on the pit walls, private LTE or 5G for dispatch and autonomy, blast vibration and dust at the fence, on one site network.The full field →Specialized fieldUnderground hard-rock mining
Microseismic arrays, ventilation on demand, gas and refuge monitoring, people and vehicle tracking, and a private LTE or leaky-feeder backbone that follows the headings.The full field →Specialized fieldUnderground coal mining
Methane, airflow and carbon monoxide under explosion-protection rules, dust exposure, communication and tracking that survive an emergency, and methane drainage measured for safety and emissions.The full field →Specialized fieldIn-situ recovery
Wellfields that dissolve ore underground, watched through monitoring-well rings, wellhead flow and pressure, groundwater chemistry and leak detection, with every excursion caught and reported.The full field →Specialized fieldQuarrying and aggregates
Blast vibration and air overpressure at the neighbours, boundary dust, noise, discharge water and face stability, on simple, low-cost links for a site that sits next to a town.The full field →Specialized fieldTailings storage facilities
Piezometers, inclinometers, GNSS, satellite radar and water balance for tailings dams, with trigger levels from the engineer of record and evidence aligned to the global tailings standard.The full field →Specialized fieldSeabed and marine minerals
Environmental baselines and plume monitoring for nearshore dredging and seabed mineral exploration: moored and seabed instruments, ocean-ready links and data that regulators and scientists can verify.The full field →Bring us the site.
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