Sewage treatment monitoring regime gets an update
Five-yearly audits give way to annual inspections for waste water treatment sites under new guidance from the Environment Agency.
The Environment Agency's regime for monitoring waste water treatment facilities has been updated with new guidance on how to carry out an Operator Monitoring Assessment (OMA). The guidance covers sites that discharge to water subject to the Environmental Permitting regulations (EPR), Operator Self-Monitoring (OSM) and the Urban Wastewater Treatment Directive (UWWTD). Although the updated OMA guidance is primarily intended for use by Agency staff, it can also be used by site operators to prepare for inspections.
The biggest change in the new version of the guidance document (Guidance on undertaking an Operator Monitoring Assessment of discharges to water subject to Operator Self-Monitoring and Urban Wastewater Treatment Directive self-monitoring, Version 2) removes a previous requirement for five-yearly UWWTD audits at sewage treatment works that are subject to UWWTD self-monitoring. Instead it introduces a requirement to carry out a UWWTD OMA each year.
This change brings the guidance into line with a new 'operational instruction' document for Environment Agency inspectors, which tells them how to carry out audits, site inspections and sampler assessments at water company sites subject to OSM and UWWTD self-monitoring. Water company site inspections, sampler assessments and audits for OSM and UWWTD operator self-monitoring (operational instruction 97_09) was issued on 14 March.
Self-monitoringSelf-monitoring has been an increasingly important aspect of the regulatory framework for environmental protection in recent years and OMA enables Environment Agency inspectors to identify any shortfalls and potential areas for improvement in the monitoring arrangements established by potential polluters.
OMA site inspections normally include a check that the site operator is complying with all the conditions of any permits, as well as scrutinising the suitability of sampling points and equipment. Sampler assessments check that anyone taking samples has been properly trained and that the arrangements for scheduling, collecting, transporting, storing, analysing and reporting any samples are all up to scratch.
Risk assessmentThe Agency takes a risk-based approach to its inspections, with the frequency and thoroughness of any programme of visits designed to be proportionate to the environmental risk presented by each site.
Operational risk appraisal (Opra) was introduced in April 2011 as the risk assessment tool to help inspectors size up that risk, so one of the first steps for site operators is to calculate where they sit on the Opra spectrum. While standard permits can be issued for sites discharging small amounts of secondary treated domestic sewage, municipal sewage treatment facilities will generally be classed among the most complex class of sites, which are known as Tier 3.
The variable permits issued for Tier 3 sites take account of specific local issues and activities. The full Opra assessment is based on five key attributes: complexity, emissions and inputs, location, operator performance and compliance rating. These are combined to produce a banded profile that the Environment Agency can then use to determine how much regulatory effort it needs to put into the site and how much it will charge the site operator for carrying out the work.?
Extra unprogrammed site inspections may be added into the schedule in response to specific incidents, and up to five additional site inspections may be programmed for each water service company to focus on UWWTD monitoring at sites that are not otherwise deemed a priority.
The four elements of OMAOMA inspections are structured into four sections, each containing a number of elements against which the Agency will score the operator's monitoring arrangements.The management, training and competence of personnel are all in the first section. The second covers the fitness-for-purpose of monitoring methods, and includes an element regarding the certification of equipment. The Agency's Monitoring Certification Scheme (MCERTS) is designed to ensure that any kit and labs involved in the process are capable of delivering accurate and reliable results, and lists of MCERTS-approved equipment is available online.
The maintenance and calibration of monitoring equipment is in the third OMA section, while quality assurance forms the fourth and final piece in the puzzle.
Each element in each section is scored separately and the overall result is derived from an appropriately weighted combination of them all.
Any deficiencies identified during an OMA inspection are reviewed on an ongoing basis, while significant changes to the monitoring arrangements may spark an extra OMA review.
An evolving systemThese systems are already well established for many industrial sites operating under the EPR. The new guidance effectively brings waste water treatment sites operating under UWWTD under the same permitting and self-monitoring umbrella.?
In the longer term, the Environment Agency expects to extend the use of OMA to other regulatory regimes. A harmonised approach to its inspections should enable it to deliver a more cost-efficient and effective service to site operators.
ABB has been a keen supporter of the Environment Agency's drive to ensure accurate monitoring measurement and reliable data for robust self monitoring regimes.
MCERTified products like WaterMaster electromagnetic flow meters are available and ABB Service Engineers are supporting industrial operators and wastewater companies with onsite electronic verification, VeriMaster certificates, sound installation advice, commissioning and other services.
ABB has also just opened a new dedicated operator training facility at its Flow Meter and Analytical Manufacturing site in Stonehouse, Gloucestershire. Operators can improve competency with monitoring and measurement equipment and see calibration laboratories.?