For the final 9 years, Severn Trent Providers, has managed a contract for mine water remedy throughout the Coal Authority property, together with 73 mine water remedy schemes in England, Scotland and Wales. These schemes take the type of three varieties: passive, pumped-passive and energetic. Water ranges are one of many components monitored carefully at these websites, which have roughly 600 monitoring factors. The vast majority of the readings are obtained manually with dip tapes, and by utilising loggers, round 125 of that are OTT ecoLog water degree loggers.
At most websites, mine water is pumped to a remedy facility which employs oxygenation, filtration and sedimentation to lift the standard of the water in compliance with discharge consents.
“Mine water from legacy coal mines is handled at many of those websites utilising settlement lagoons and reed beds,” explains Oren Environmental’s Knowledge & Reporting Supervisor Paul Robinson. “The efficient administration of those sources is closely depending on dependable information together with water degree measurements, and we’ve got been utilizing OTT devices to assist this since 2016. With the advantage of water degree information, we will make sure that the movement of water via the lagoons and reedbeds maximises efficient remedy earlier than water is discharged to watercourse.
“One of many extra capabilities of the loggers is to create alarms and that is one thing we’re investigating for future use,” Paul explains.
“Along with the older ecoLog 500’s and the newer ecoLog 1000’s, we additionally utilise 5 ecoLog 800’s to gather and monitor conductivity measurements. Conductivity information can be utilized to evaluate the standard of water by figuring out minerals and many others. which might be current within the water.”
The place the ecoLogs are deployed in floor water weirs, the extent measurements are translated into movement, which additional informs the administration of the remedy course of.
Most of the authentic water degree loggers have been ecoLog 500 units, a few of that are nonetheless in operation. Nevertheless, these are being steadily changed by ecoLog 1000 devices. “The ecoLog 1000 has a particularly advantageous characteristic,” Paul explains. “Knowledge from the older models was collected utilizing a USB cable, nonetheless the newer devices have Bluetooth connectivity, which implies that our operators can join extra rapidly and in antagonistic climate. The place attainable, they’ll additionally drive near the logger and talk wirelessly with a smartphone or laptop computer from their car.”
The ecoLog 1000 is an all-in-one instrument, together with a water degree sensor, a logger, and a built-in modem. It requires no extra instruments for upkeep or battery substitute, and has been designed for long-term, unattended monitoring in difficult circumstances. Key options subsequently embody extraordinarily low-power operation together with Bluetooth Low Power, in addition to a rugged stainless-steel strain probe housing and a ceramic temperature compensated sensor. Usually, distant connectivity is achieved by way of mobile community LTE-M (Cat-M1).
Power Crag Mine within the Lake District is an efficient instance of a particularly distant former mine with difficult environmental circumstances. Mobile protection may be very restricted on-site, so OTT constructed a neighborhood community which transmits water degree information by way of radio to 2 loggers situated in a better place. Knowledge from these loggers are then transmitted repeatedly to Oren’s FTP Server.
Mining commenced at Power Crag in 1835, and it grew to become the final working steel mine (zinc, lead and barytes) within the Lake District, previous to its last closure in 1991. Metallic air pollution (zinc, cadmium and lead) from the mine polluted the Coledale Beck, a tributary of the River Derwent and Bassenthwaite Lake Particular Space of Conservation.
The Coal Authority, working in partnership with the Surroundings Company, Newcastle College and the Nationwide Belief, devised an modern passive mine water remedy scheme to cut back the degrees of steel air pollution coming into the river. The scheme, which formally opened in 2015, diverts water from the Stage 1 adit (horizontal passage to an underground mine) and routes it via a buried switch pipe to 2 vertical movement ponds for remedy.
The ponds have been constructed utilizing the prevailing bunding of the previous mining tailings lagoon, lined with a geomembrane, and full of a compost remedy combine. Water is fed into the ponds, the place it flows down via the compost and passes right into a wetland, planted with smooth rushes. The wetland filters any remaining solids and oxygenates the water previous to discharge into the Coledale Beck.
“Every web site presents its personal challenges,” Paul Robinson explains. “Many are in distant areas and in several environments, so we do our greatest to make sure we maximise the tools handy such because the OTT ecoLogs.” Wanting ahead, he says: “Distant telemetry is especially advantageous, as a result of it supplies entry to extra frequent information than guide dips as a result of schedule of visits that we work to.”
