WPD-Case study-FINAL4

CASE STUDY

Western Power DistributionPole Storage Creosote Pollution & ISO14001/EA Compliance Challenges

ase study

Case Study: Western Power Distribution / Pole Storage Creosote Pollution & ISO14001/EA Compliance Challenges 1

The Western Power Distribution (WPD) Wapley site had an imminent ISO 14001 audit. The facility had no containment provision around the pole storage area and some contamination was occurring from creosote leaching out of the poles and into the environment. This would lead to a non‐compliance during the annual ISO14001 audit and failure to adhere to Environment Agency regulations, specifically PPG5. The Depot and Environmental Managers needed to identify a quick, effective and permanent solution to be installed and commissioned prior to the site audit.

CONTENTSBackground

Solution

Environmental Compliance

Health and Safety Risk Liability Decreased

Reduced Project & Operational Costs

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3

5

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BackgroundWestern Power Distribution utilise high volumes of creosote impregnated distribution poles during its day‐to‐day operations. Distribution poles are installed during planned capital works programs, repair and maintenance, and emergency works. The high volume of planned and reactive installations means that WPD need to store creosote impregnated timber distribution poles at strategic geographical locations across its network.

A positive environmental impact is a paramount concern and focus for any WPD facility, and this directly influenced a review and upgrade of the environmental protection systems to prevent pollutants entering the ground at Wapley (Bristol) sub‐station ‐ home to a distribution pole bulk storage site.

The facility had no containment provision around the pole storage area and some contamination was occurring from creosote leaching out of the poles and into the environment. This would lead to a non‐compliance during the annual ISO14001 audit and failure to adhere to Environment Agency regulations, specifically PPG5. The EA has the power to apply financial penalties for non‐compliance and/or pollution of the environment up to a £50k maximum.

Utility pole storage with no environment protection.

The Western Power Distribution Wapley site had an imminent ISO 14001 audit, so the Depot and Environmental Managers needed to identify a quick, effective and permanent solution to be installed and commissioned. Capture Green was engaged by WPD to undertake an evaluation, then propose and recommend a resolution that could be implemented and delivered in an extremely cost efficient way.

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Full site survey and written proposal development completed within 1 4 days.Construction start date within 1 3 days of WPD’s proposal acceptance.No significant or timely groundwork preparation.No or only a small amount of concrete construction formations.A permanent solution to creosote pollution at a significant lower CAPEX to comparable concrete containment.Easy access for inspection and service.Low frequency of preventative maintenance interventions.Full polluted water remediation to meet with the EA’s excepted discharge levels.A solution which assimilates with the surrounding area.Complete project delivered and commissioned within 3 weeks.

The stakeholders outlined the following criteria which Capture Green needed to address:


SolutionA secondary containment and water remediation system for the safe compliant storage of creosote impregnated timber utility poles.

Capture Green has worked closely with WPD to design a pole storage system that ensures it meets its corporate, social and regulatory responsibilities by preventing creosote contaminants from entering the environment. The system has also been designed to work to the specific requirements of the site.

Secondary containment and water remediation system for the safe compliant storage of creosote impregnated timber utility poles.

The secondary containment installation comprises of two 135m2 (9x15m) storage bays that join end‐to‐end. Both bays are hydraulically linked. The containment areas have been formed with a selection of resilient impermeable and puncture‐resistant membrane materials, on an area of stabilised land capable of withstanding the loads subjected by a quantity of stored distribution poles.

Situated at the centre of the two bays, buried beneath the final level of pea shingle reinstatement, is a water retention area, also known as a sustainable (urban) drainage system (SUDS). This is essentially a void created below the ground that enables large volumes of water to be stored before processing or natural ground percolation occurs. Capture Green Ltd integrate this feature to alleviate the burden on the remediation system during heavy rainfall and flash flooding. The retention area slows the drainage process down, ensuring the remedial chamber has time to process contaminated surface water.

A stillage is formed in each bay to prevent excessive movement of stored poles. The stillage comprises of driven vertical timber posts that are held in place with structural concrete. Timber laterals are bolted between the uprights and these form bearers that the stored poles sit on top of. The laterals timbers not only spread content weight but also keep the load off the ground. This brings a number of benefits in areas like water flow, logistics, and protecting the liner by lifting the load off the bed of the site. HDPE top hat sleeves are formed around timber uprights and fused to the lined base to seal the joint between the two components.


Each bay has been designed to hold around 80 poles. Together, the two bays enable approximately 160 poles to be safely stored at the site.

During the design phase, it was decided that a third bay may be required at a later date. With this in mind, Capture Green designed the water remediation system with enough capacity that a third bay could be easily linked to it at a later date.

The Capture Green Water Remediation Chamber houses a number of water processing devices that remove compounds typically found in water arising from pole storage sites. This includes hydrocarbons (used for diluting the creosote down), sediment and debris (often contaminated), phenols and cresols.

There is a common misconception that traditional oil water separation systems can be installed to carry out the task of removing creosote from water. This is not the case – and inevitably results (carcinogenic) Polycyclic Aromatic Hydrocarbons PAH’s migrating into the environment. Water solubility increases as compounds start to breakdown (emulsify), particularly during warmer months. Compounds less dense than water that would typically be separated in a conventional system can be carried through the discharge point as they adhere to heavier contaminants. To counter this, Capture Green have design a remediation system specifically for creosote, utilising a number of proprietary filtration and biological processes to remove compounds (typically found in creosote) from surface water.

Discreet Compact Water Remediation Chamber

WPD Wapley Capture Green Pole Storage Layout


Health and Safety Risk Liability DecreasedIt is important to acknowledge all of the health and safety benefits associated with the installation and utilisation of the Capture Green Pole Storage System. These are not just limited to the “day‐to‐day” operational use.

The Pole Storage System at Wapley took 3 weeks to install. Contrastingly, a typical concrete containment installation at a site the size of Wapley would take around 10 weeks to construct. This demonstrates a 70% reduction in time on site and a significant reduction in the possibility of time on site associated health and safety breaches.

Looking at ongoing health and safety benefits, the stillage installed within the containment area aids risk management efforts by minimising pole movement during loading and unloading. Capture Green have also designed a clear, safe working area around the stillage, reducing potential contact between plant, poles and operatives.

Reduced Project & Operational CostsSince Capture Green have pioneered the creosote containment and removal concept within the industry, direct cost comparisons are a challenge. Capture Green are aware that some of its clients have built concrete containment areas costing hundreds of thousands of pounds. Carrying out an analysis of the particulars of the site against a hypothetical concrete containment design, we are confident that cost savings will be in the region of 30 to 35% less CAPEX. This is a direct comparison of a concrete containment area against a turnkey Capture Green containment and remediation solution, not accounting for the ongoing operational costs of vacuum tankers to remove contaminated water.

Environmental ComplianceThe system has been solely designed to mitigate environmental risk. It is an offence to knowingly pollute the environment by allowing harmful compounds to enter it. The system design and installation ensures that WPD always remain compliant and importantly meet ISO14001 requirements.

Completed Bulk Pole Storage Facility

6Case Study: Western Power Distribution / Pole Storage Creosote Pollution & ISO14001/EA Compliance Challenges

Further information

+44 (0) 1206 299388Address:

Unit 3 Gattinetts Hadleigh Road East Bergholt Colchester C07 6QT [email protected]

www.capturegreen.com

About the Author

Rees Westley is an accomplished and dynamic project manager, helping develop pollution prevention solutions for electrical utilities. He’s used to working in the most challenging and deadline-driven industry environments. His ability to instill a “can do” positive attitude creates a motivated, cohesive team, enabling the safe delivery of a project, on time and under budget, with healthy profits.

Capture Green Limited is a company dedicated to providing electrical utilities with total solutions to prevent dielectric fluid and creosote pollutants entering the eco‐system, therefore protecting the environment.

Rees Westley Operations Director at Capture Green Limited

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