MCERTS schemes for water monitoring
The various Environment Agency Schemes have been rolled out over the last 10 years and include the following;
Ø Continuous emissions monitoring systems
Ø Manual stack emission monitoring
Ø Automatic Isokinetic Samplers
Ø Portable systems for air emissions monitoring
Ø Continuous ambient air quality monitoring systems
Ø Continuous water monitoring equipment
Ø Portable water monitoring equipment
Ø Self-Monitoring of effluent flow
Ø Chemical testing of soils
Ø Environmental data management software
MCERTS schemes focused at the water industry
These schemes for the water monitoring industry have seen the most significant advancement.
Self monitoring of effluent flow
MCERTS sets a target of +/- 8% uncertainty for the total daily volume of effluent discharged. The scheme has already been successfully applied to the ten Water Utilities where nearly 3000 MCERTS site conformity inspection certificates have been issued. MCERTS has also been applied to industrial installations with effluent flow monitoring limits included in their Environmental Permitting Regulation (EPR) permits. Many inspections have taken place and we are working with industry to complete the remaining inspections as soon as possible.
Flow monitoring inevitably measures high if it is not installed correctly or properly maintained. Following the MCERTS inspections there have been cases of significant cost savings made by operators - up to £100,000. Measuring flow correctly also allows operators to manage their process to identify product loss and minimise water/power use.
MCERTS: self monitoring of effluent flow is now being considered for introduction to other sites that we regulate with effluent flow monitoring specified in their permit such as:
Ø non Water Utility sites regulated under the Water Resources Act
Ø sites regulated under the Radio Active Substances Act
Ø other EPR sectors such as the waste industry.
Water monitoring equipment
MCERTS sets out our performance requirements and test procedures for three types of continuous water monitoring equipment and for analytical portable water monitoring equipment. Testing includes both laboratory and field trials to provide evidence that the performance requirements can be achieved. This evidence can be provided by data from new tests or in certain circumstances by using existing traceable and verifiable data. An audit of the manufacturing process is also a MCERTS requirement. This audit ensures that all equipment is produced to the same standard.
Parameters included in the on-line analyser standard are: Turbidity; pH; ammonia; COD; TOC; dissolved oxygen; total phosphorus; nitrates; total oxidised nitrogen. Conductivity, total chlorine and free cyanide were added to the latest version of the MCERTS standard published in March 2008. The addition of toxic metals is now being considered.
Direct toxicity assessment of effluents
Direct toxicity assessment (DTA) is a technique used to measure the environmental hazard (toxicity) of a complex effluent and assess the whole effluent toxicity. DTA complements traditional substance specific testing, and is particularly useful for complex effluents where it provides an integrated assessment of all constituents, some of which may not have been identified or be amenable to chemical analysis.
Six laboratories have now gained approval to carry out regulatory work for the Environment Agency by following our published test methods, having an appropriate quality management scheme and participating in the EA DTA proficiency testing scheme (DTAPS). The list of approved laboratories is available on the MCERTS website.
Five test methods have been published, covering both fresh and saline waters:
1. Daphnia magna immobilisation
2. Freshwater algae inhibition of growth
3. Oyster Embryo-Larval development
4. Tisbe battagliai lethality
5. Marine algae inhibition of growth
The DTAPS scheme has been granted accreditation by UKAS and the fourth annual round has been distributed. Reports from previous rounds of DTAPS are available on the MCERTS website.
Sampling and analysis
An MCERTS performance standard has been developed to cover sampling and analysis of effluents. Initially it will be applied to sewage treatment works effluents regulated under the WRA, because Water Companies are moving towards an operator self monitoring regulatory regime. Water companies will be required to ensure that all sampling and analysis of effluents comply with this MCERTS performance standard. MCERTS provides formal accreditation in accordance with European and international standards.
The standard makes sure that the Environment Agency, the public and other organisations involved in the testing of sewage effluents can be confident that the test results presented are reliable and of an appropriate quality whatever the source.
This MCERTS scheme is based on the requirements of the international standard ISO 17025, which is a general standard for competence of testing and calibration laboratories. ISO 17025 recognises that it may be necessary to develop applications to supplement the standard for specific fields of sampling and analysis. The MCERTS ”Performance Standard for Organisations Undertaking Sampling and Chemical Testing of Water: Part 1 - Sampling and chemical testing of untreated sewage, treated sewage effluents and trade effluents” is one such application.