Wastewater Treatment plants suitable for use in Ireland
The National Standards Authority of Ireland (NSAI) in May 2015 published Standard Recommendation S.R. 66:2015. It provides guidance on small wastewater treatment products tested to the European standard EN 12566 series for use in Ireland. It reiterates the performance requirements outlined in the original National Annexes as well as including requirements relating to the number of de-sludgings carried out during the treatment efficiency test. It also introduced comparibility requirements for the tanks of small wastewater treatment products with shared ITT, which must be complied with. Where a family of products exist, claiming the same performance as the tested model, scaling rules were introduced.
The Dept. of Housing, Planning, Community and Local Government has amended the Technical Guidance Document H (TGD H) - Drainage and Waste Water Disposal to reference S.R. 66:2015 and remove references to national annexes. The amendments to TGD H will become effective from 1st January 2017 and all works started after that date involving small wastewater treatment systems will have to comply with the requirements of S.R. 66:2015. This means that all Wastewater Treatment products have to be in compliance with S.R. 66:2015 to be eligible for use in Ireland. In response to this and to ensure that appropriate certification is available to show compliance with S.R. 66:2015, PIA has developed a new list of products. These lists of products have been setup in consultation with the Irish Department of Housing, Planning Community and Local Government.
Small Wastewater Treatment Plants
Tested to the EN 12566 Standard Part 1/4, Part 3 or Part 6:
The certificates only give brief information. Technical details concerning the installation, maintenance and operation can be found in the manufaturers instructions, they cannot be derived from the information on the certificates.
Where manufacturers have a range of products claiming the same hydraulic/ treatment efficiency results, the certificates lists the plants in the range that meet the scaling rules outlined in S.R. 66:2015.
The listed certificates replace neither the declaration of conformity nor the CE marking.
Septic Tanks (Part 1/4)
Septic Tanks tested by a notified body to EN 12566 Part 1 - Pre-fabricated septic tanks, or Part 4 - septic tanks assembled insitu from prefabricated kits are listed with their certification displayed in a manner suitable for comparison with the requirements of S.R. 66:2015.
List of certificates in accordance to Part 1/4 and S.R. 66:2015 (in alphabetical order):
Septic Tanks S.R. 66:2015
NOTE 1: Capacity
The nominal capacity is only the numerical designation of the volume of a septic tank, expressed as an integer in cubic metres as required by the standard. Each tank in the range is declared as a separate nominal capacity on the certificate.
The usable capacity which is the total volume of the tank to the outlet invert level is also declared. This value is needed to fulfil the requirements of the following formula defined in the Environmental Protection Agencies Code of Practice- Wastewater treatment and disposal systems serving single houses and required by the Irish Building Regulations:
C = 150 x P + 2000 where C is the capacity (l) of the tank and P is the design population, with a minimum of four persons.
NOTE 2: Range
Scenario 1: The septic tank range of a manufacturer consists of three different tanks with usable capacity of 2,800 l, 3,800 l and 4,600 l.
So the nominal capacity is 2 m³, 3 m³ and 4 m³. All three of them were tested according EN 12566-1.
The hydraulic efficiency test was done on the 2 m² tank, the structural test was performed on the 4 m³ tank and the watertightness test was done on all of them.
Scenario 2: The range of a manufacturer consists only of one tank with a usable capacity of 4,600 l, and all relevant tests were performed on this tank. So the nominal capacity is 4 m³ with a usable capacity of 4,600 l. It is not possible to downscale this plant, e.g. to use it as a 2 m³ tank because the hydraulic efficiency was done on the 4 m³ tank.
Packaged Treatment plants (Part 3)
Wastewater treatment plants tested by a notified body to EN 12566 Part 3 - Packaged and/or site assembled domestic wastewater treatment plants, are listed with their certification displayed in a manner suitable for comparison with the requirements of S.R. 66:2015. The declared results as shown on the certificates are valid for an average test influent of 300 mg/l BOD5 or greater and when desludged not more than once during the test as required by S.R. 66:2015.
Where small wastewater treatment plants are produced by two manufacturers sharing other party results, ie one company produces the tank and the other manufacturer produces the technical kit (shared ITT), the standard EN 12566-3 requires that only one manufacturer is responsible for the compliance of the product. The manufacturer who places the product on the market is responsibility for the compliance with the requirements of all aspects of the wastewater treatment plant.
List of certificates in accordance with Part 3 and S.R. 66:2015 (in alphabetical order):
Packaged Treatment plants S.R. 66:2015
Secondary treatment plants receiving effluent from septic tanks (Part 6)
Wastewater treatment plants tested by a notified body to EN 12566 Part 6 – prefabricated treatment units for septic tank effluent, are listed with their certification displayed in a manner suitable for comparison with the requirements of S.R. 66. The declared results as shown on the certificates are valid for an average test influent of 300 mg/l BOD5 or greater.
The Part 6 unit must be installed in conjunction with a Septic Tank meeting the performance requirements for septic tanks stated in the S.R.66 (see above list)
As per S.R. 66, where it is proposed to retain an existing septic tank to be used with a secondary treatment system certified to EN 12566-6.
The septic tank to be retained should:
- Be structurally sound
- Be water tight
- Have a capacity in conformance with the EPA CoP for the size of the dwelling
- Be fitted with a suitable filter on the outlet.
List of certificates in accordance with Part 6 and S.R. 66 (in alphabetical order):
Secondary treatment plants receiving effluent from septic tanks