Sustainable water management system installed to dewater Quarry's Lagoon
Overview
Wenvoe Quarry near Barry, South Wales is a limestone quarry producing a range of construction aggregates and other lime products.
With a carboniferous limestone seam of over 260 metres and a very thin overburden layer, the modern-day Wenvoe Quarry has been operational since 1976.
Robust, efficient and compliant water management is important to quarry operator Breedon Group. The quarry has two areas with one being currently extracted and the older part now the crushing and screening area. A tunnel connects the two zones, with run-off water collecting in a lagoon wedge pit. When the silt has settled, water is pumped off for licensed discharge.
Challenge
The Breedon Group wants to remain at the forefront of environmental management and protection. To this end, they sought a better way to efficiently control and monitor their site water discharges.
Accurate record keeping improves decision making and stakeholder confidence, whilst providing the required data with speed and ease during inspections or requests from the authorities.
Wedge pits are an energy efficient and established way to clarify muddy water, allowing gravity the time to settle-out suspended silt and grit. Water is then drawn off the top when it is tested to have cleared sufficiently. However, working to this alongside the daily discharge limitations set by the environmental permitting authority, plus operational and weather events, puts a significant strain on management time.
Accurate water discharge logging records must be kept, for showing to the Environment Agency upon request, adding additional burden on the nominated person and introducing the risk of human error at many points.
The Cadoxton River, a small but important trout stream is in the vicinity of Wenvoe, so stringent environmental protection and monitoring helps ensure that this is protected at all times.
Introducing even inert silt can damage watercourses by blocking sunlight, changing flow patterns, reducing depth and blocking channels. Whilst Wenvoe Quarry has never been known to pose a risk to their surrounding watercourses, it has come at a high operational cost for the operator. With climate change bringing us frequent extremes and the desire to do more to support our environment, such operational challenges are poised to increase.
Solution
After searching the quarry water treatment market, Breedon answered these issues by tasking Atlantic Pumps to design and install an EnviroHub water monitoring unit, along with everything necessary to pump the tested water from the settlement lagoon to the discharge point.
Minimal energy use and reduced maintenance were also key to the successful design, specification and installation of this water treatment and control program.
The reason Atlantic Pumps were chosen came down to them having a proven solution that is designed, built and installed by one company, that could also give long-term support and aftersales backup.
With the new integrated pump and control package, EnviroHub’s intelligent monitoring automatically stops any non-compliant discharge, be it for excess volume, flow or lack of clarity, at any time of day or night.
When a pre-set ‘soft’ target is reached, the EnviroHub Monitoring Unit issues a warning SMS text message or email to management, whether they are within range or off-site. If no manual intervention happens and the readings continue their trend, the pump system will shut down before ‘hard’ limits are exceeded.
If the pumping suspension was due to volume limitations, the system restarts the pumping and testing cycle when into a new period, maximising daily discharge allowances in line with permit permissions. If the water is (still) cloudy, the pump turns off again for a pre-programmed time before re-testing and resuming discharge if clear.
Typical events that can cause suspended silt to contaminate site discharge water include storms, heavy rain or large-scale site operations. As some of these situations can occur out-of-hours or with little warning, the automation of EnviroHub’s environmental protection increases resilience and reduces residual risk.
EnviroHub is a modular system that can be added to as needed to meet future challenges or changes to requirements. For example, if the quarry ever requires a faster settlement process, a lamella settlement tank and flocculent dosing treatment module can be added. These EnviroHub modules reduce the need for a wedge pit, allowing more space for extraction, storage and processing equipment.
With EnviroHub constantly monitoring the clarity and volume of discharge water, and taking automated action to prevent pollution, quarry staff, the public, and the environmental authorities can have confidence that important tasks won’t be overlooked.
Products used in this dewatering and discharge system
- EnviroHub Monitoring system which included a 10” inline Monitoring Unit.
- Audex AS 6-7500 - 8” 75kW submersible pump, mounted on a bespoke pontoon.
- Senteos – the remote communication and secure portal for EnviroHub.
- 75kW Control Panel.
- 8” pipework with pipe floats.
Site water discharge – risk-free compliance for efficient site water disposal
EnviroHub monitors, records and treats site water for pH, temperature, solids content, flow and volume. On-site and off-site secure monitoring and control. For further information, please call our Sales team on 0800 118 2500 or click here to fill out our contact form.