As reported in the last issue of IET the Environment Agency, who regulate England and Wales, established its Monitoring Certification Scheme: MCERTS nearly ten years ago to deliver quality environmental measurements. The scheme has evolved over this time to provide for the product certification of instruments, the competency certification of personnel, an inspection scheme and the accreditation of organisations based on international standards. One of the recent extensions to MCERTS has been to cover all regulatory monitoring activities for water industry applications which includes product certification of Continuous and Portable water monitoring equipment. Details of this part of the scheme is as follows;

MCERTS - Continuous Water Monitoring Equipment:
The Environment Agency is interested in the monitoring of waste-water discharges and receiving water quality as a means of assessing the environmental impact of the industries it regulates. Actions can then be taken to prevent, or minimise, any impact and prevent potential harm from occurring.

Continuous water monitoring equipment must be of an acceptable standard to ensure that the environment remains properly protected. Regulations such as Pollution Prevention and Control (PPC) require operators to use MCERTS approved products. Equipment is certified and tested under the MCERTS Continuous Water Monitoring Equipment scheme, which covers three types of equipment:

• Automatic wastewater sampling equipment
• On-line analysers for turbidity, pH, COD, TOC, dissolved oxygen, total phosphorous, nitrates and total oxidised nitrogen
• Water flowmeters

MCERTS - Portable Water Monitoring Equipment:
The requirements for certain types of portable water monitoring equipment are also addressed. Portable water monitoring equipment is used for the monitoring of water and waste-water, rivers, lakes and estuaries, reservoirs, boreholes and trade effluents. The determinands covered include temperature, pH, conductivity, dissolved oxygen, turbidity, ammonia, nitrate, nitrite, orthophosphate and chlorophyll a. This list of determinands may grow in the future if there is sufficient support from manufacturers and/or user groups.

A number of instruments have gone through certification and many more are in the process, for full details visit www.mcerts.net. Examples of MCERTS equipment in use and experience of certification is highlighted in the following case studies;

Case Study 1:
Turbidity monitors, supplied by Partech Instruments, contribute to high accuracy flocculent dosing at Devon land fill site

A problem that almost all landfill sites face is the treatment of surface water run off and in particular removing suspended solids prior to discharge. Where the landfill site is at Deep Moor in a rural area above one of the Devon’s most beautiful river valleys and haven for aquatic wildlife, the problem is all the more acute.
For Devon Waste Management, surface water run off from its Deep Moor site outside Great Torrington, goes back into the water course and eventually back into the River Torridge. However, before it is discharged into a local stream, the water is subjected to a treatment process that following an upgrade in 2005 now incorporates a flocculent doing system that is reliant on the performance of two Partech Turbi-Tech monitors.
Accepting 85,000 tons of domestic and commercial waste a year, Deep Moor is Devon Waste Management’s only landfill and covers some 35 hectares. Around 50% has already been fully landscaped and a further 30% is currently being landscaped, leaving 20% that is currently active. All of the roads and partially restored areas generate surface water and this collects at the lowest point on the site. The Environment Agency’s discharge consent level for the site is 60mg/l of suspended solids.

In addition to this constant monitoring, the discharge stream is monitored weekly both by ourselves and the Environment Agency.”
“The dosing system is very special because we have always wanted to ensure that the site has operated a truly effective system, “continues Colin Brown. “The success of the system is down to Greenacre who were able to combine their knowledge of pumping systems with an awareness of the capabilities of Partech’s turbidity monitors. The challenge that we face here at Deep Moor is the very wide turbidity which results from the different conditions on site. Coupled with this are the varying water run off flows which can range from 10l/sec up to 80l/sec. The system had to cope with a huge range on both scales.
The dosing control system reads both the turbidity and the flow and then works out the dosage and multiplies the dosage according to the flow. It is simple to describe, but to get a workable system was a much more challenging design problem.
The effectiveness of the flocculent dosing system has been quickly identified by the operators at Deep Moor, who report that since the system was commissioned in the autumn of 2005, it has provided the highest levels of accuracy and efficiency throughout the rigours of winter and the unusually dry summer.

Case Study 2:
Emerson Gains MCERTS Approval for Rosemount Analytical® pH Analysers

Approval applies to analysers used for pH monitoring in England & Wales.
Emerson Process Management has gained UK MCERTS approval for its Rosemount Analytical range of pH analysers and sensors, which are used to monitor process conditions and discharges to rivers, smaller watercourses and the sea in England and Wales. The certificates were issued by Sira who operate the MCERTS scheme in England and Wales on behalf of the Environment Agency.
The approvals cover any combination of Rosemount Analytical Xmt, 54e, 1055 and 5081 transmitters with 399, 399VP and 381+ sensors. These products have been tested and found to comply with the Environment Agency’s performance standards for continuous water on-line analysers. Emerson Process Management is currently the only company to have successfully obtained MCERTS approval for pH analysers and sensors, and this involved working closely with the Environment Agency throughout the process.
Businesses that make emissions to air, land and water are regulated by the Environment Agency under strict European, English and Welsh laws, to protect the environment and human health. Permits are issued to enable companies to operate and this normally requires emissions to be monitored to ensure they meet the necessary quality standards.

“Operators are being increasingly required to continuously monitor their discharges and provide valid records to us,” said Paul Wiggins, Technical Adviser, of the Environment Agency. “Cornerstone to this scheme is the confidence that the records submitted are from an instrument that is both accurate and reliable. Data from an instrument which has MCERTS approval will normally be accepted without any further evidence being required, allowing operators to run their businesses in the most efficient way. Our policy is that where MCERTS equipment is available and appropriate, we expect operators to install it.”
In order to be granted MCERTS approval, analysers are performance tested in the laboratory, and must undergo three months of field trials – or the manufacturer must submit field data from existing installations – in order to assess factors such as accuracy, repeatability, linearity and long term stability.
To meet the requirements for field data, Emerson used the records from a Scottish and Southern Energy (SSE) installation at Keadby Power Station near Scunthorpe, where Rosemount Analytical sensors are used to continuously monitor the pH of water which is extracted from the river and used for cooling. The on site laboratory had been analysing samples independently so that direct comparisons could be made between the laboratory results and instrument readings.
“We appreciate the assistance that the SSE’s Team at Keadby Power Station have given us in helping Emerson gain MCERTS approval,” said Stéphane Canadas, Business Development Manager for Emerson Process Management. “Emerson is committed to ensuring that its products meet the latest industry standards. Using products with MCERTS approval brings many operational benefits for our customers while ensuring their operations meet strict environmental standards.“
“By submitting its products for independent testing, Emerson has demonstrated its confidence in the performance of the Rosemount Analytical analysers,” said Paul Wiggins. “Emerson has worked closely with the Environment Agency and Sira to help develop this particular scheme and we are pleased that these products have been awarded MCERTS certificates.”
The MCERTS Scheme is formally recognised in England and Wales and accepted internationally. It provides instrument manufacturers with an independent authoritative endorsement of the practical performance of individual products.
Companies listed above are some of the founder members of the Water Monitoring Association (WMA) which has been set up this year WMA represents the interests of companies involved in all aspects of water monitoring.
It was formed to influence the development of standards, equipment, personnel and applications that affect qualitative and quantitative water monitoring.
The objectives of the Association are to;

• provide an independent technical resource for members and their clients;
• influence appropriate industry standards, codes, safety procedures and operating principles;
• encourage the professional development and a high level of ethical conduct of industry personnel;
• seek co-operative endeavours with other professional organisations, institutions and regulatory bodies, nationally and internationally.

Membership is open to any company or individual that has an interest in the monitoring of water and related fields. For more details of WMA visit: www.w-m-a.org