Dr Richard Coulton, CEO at Siltbuster, talks to us about the Environment Agency’s new Regulatory Policy Statement and the impact it has on the construction industry as a whole.
On 7th February 2018 the Environment Agency published a new Regulatory Policy Statement (RPS) entitled ‘Temporary Dewatering of Excavations to Surface Water’. The statement sets out the circumstances under which water can be discharged off site without the need for a Bespoke Discharge Permit. It also states that contractors need a permit if they want to discharge off site into the surrounding environment for anything other than clean water.
It’s important that the construction sector gets to grips with these changes especially with the new sentencing guidelines in place. These are resulting in a growing number of high fines being metered out. For instance, the Environment Agency recently prosecuted a Leeds-based house building company £120,000 for illegally polluting a watercourse, by not controlling silty run-off.
So, When Are Permits Necessary?
Bespoke Discharge Permits have always been mandatory if the water being released is from land or groundwater that is known to be contaminated, or from any form of quarrying activity. However, outside of this, there have been some areas that were open to an individual’s interpretation. This is no longer the case, with the RPS providing specific directions for contractors on site.
The Discharge Must:
- Be clean water
- Not result in water containing fine or coarse suspended solids entering surface water
- Not last more than three consecutive months, including if the activity stops and then restarts
- Be made to surface water
- Have a method statement that minimises the risk of pollution
The Discharge Must Not:
- Pollute surface water
- Contain any chemical dosing agents, flocculants or coagulants
- Be from a site contaminated by oil, metals, hydrocarbons, solvents, pesticides or any other polluting substance
- Result in the spread of non-native invasive species, parasites or disease
- Cause flooding from surface water
- Erode the banks or bed of the receiving watercourse
- Contain concrete wash water, even after it has been successfully treated
- Include site drainage from surface areas, such as haul roads, storage or working areas
- Come from a site with naturally elevated concentrations of substances which exceed environmental quality standards
Before Work Starts
Given that most UK soils contain silts or clays, almost all construction projects will potentially generate unclean wastewater. Therefore, any construction work that companies predict will not meet the criteria outlined in the RPS must have a Bespoke Discharge Permit.
This means that contractors need to be better prepared than ever and more proactive in their planning around the management of excess waters on-site. They will need to implement accurate and clear plans to either treat the wastewater on-site, or find an alternative, and often more expensive, disposal route, either by tankering off-site or discharging to sewer, which requires prior approval of the local utility company.
As a collective, the construction industry will have to be more responsive to the notion of discharging water and in turn, become more educated on the subject.
Those in charge of sites will need to be able to distinguish between excess water due to rainfall and water created by construction processes, which can be extremely polluting. For example, washing down concrete lorries, produces alkaline waste waters with a pH as high as 13 (equivalent of oven cleaner), which if released back into watercourses untreated will damage ecosystems and kill aquatic life.
In addition to this, the RPS means decision-makers must determine the correct water treatment solution prior to pumping. Plus, it suggests that the use of low tech solutions, such as Floc Blocks, is riskier than ever, as the RPS now demands no carry over of any chemical dosing agents.
Planning is Paramount
The RPS effectively makes the preparation of a Site Water Management Plan prior to commencing work mandatory, no matter if a Bespoke Discharge Permit is required or not. For those sites that require a permit, a clear and well-thought-out plan is essential, not only to guarantee a permit is granted, but also to ensure the smooth running of a project once work commences.
The plan must:
- Endeavour to minimise risk and the amount of contaminated water generated by isolating clear surface and groundwater as far as possible from construction activities
- Isolate concrete wash water and any potentially oil contaminated water from the rest of the site
- Estimate the amount of contaminated water that will be generated and put in place suitable treatment methods
- Include contingency plans to cover the scenarios that are unlikely, but still possible
- Demonstrate adequate site operator training and awareness of the environmental issues associated with the risk of waterborne contamination
- Document the procedures put in place and provide evidence of compliance
Act Now
Complying with these requirements clearly requires planning and means a major increase in workload for engineering and environmental departments. Specialist knowledge of not only the proposed construction works but also the site’s hydrology and the appropriate methods of water treatment are all now needed.
To help companies prepare for this change, Siltbuster provides technical support, CPD accredited courses plus bespoke and tailored technical training days. For more information call 01600 772256, email [email protected] or visit https://www.siltbuster.co.uk/cpd-courses/.
