1. All I want is Planning Permission?

Planning Permission on its own is of no benefit. Presumably you intend to live in a development or to sell it. A manipulated Site Assessment may result in a planning refusal and will ensure pollution and future significant remedial costs.

2. Why do I need to consider who does my Site Assessment?

Under European Law the polluter pays principle is fundamental. This means that the householder is ultimately the person responsible. Think about this! Not the Architect, Engineer, Site Assessor, Builder, but the householder. If you got a “guy down the road” to do the site assessment, to design the system or to install the system, who does not have Professional Indemnity insurance for the specific task, then the problem is yours. You may engage a Site Assessor with PI insurance for site assessment, but who may not be qualified or insured to design a system. Again the problem is yours. You may have an appropriate Assessment but the Builder did not install the system as recommended or conditioned in the assessment. The problem is yours. Appropriate design and supervision by a Professionally Indemnified Chartered Engineer based on a correct Site Assessment is your guarantee that you are not ultimately responsible. We are, if you engage us.

3. Why do I need a Site Assessment?

Strictly speaking, under current Planning Legislation you may not need a “Site Assessment” per say. The requirement is founded in S.I. No. 685 of 2006 — Planning and Development Regulations 2006 and article 8 of this Regulation amends the previous Regulation to include article 22(2)(c) which states; “where it is proposed to dispose of wastewater from the proposed development other than to a public sewer, information on the on-site treatment system proposed and evidence as to the suitability of the site for the system proposed”. The two words are emphasised by us and whether these constitute a requirement for a “Site Assessment” makes for an interesting question. However, planning permission should not be your ultimate goal. A system which treats your wastewater correctly, as cost effectively as possible, potentially for the life-time of your home, is what you really require. Cutting a corner now, even if you get it past the planning process, could well cost you many thousands of Euro’s in the future. Ask your friends and neighbours who have problems with their systems or those who fear upcoming inspections.

4. What is Site Assessment?

Site Assessment for on-site wastewater treatment is commonly called percolation testing. It has evolved from the above that it is a requirement for anybody applying for planning permission in a rural (un-serviced) area. Quite apart from planning permission, and ideally long before an application for planning permission is even considered, the Site Assessment should be used to decide on whether a site can treat the wastewater which will arise if a development is constructed. It should be used to determine appropriate sites for sale/purchase or the location of an appropriate site on your own land. If a rural site cannot treat wastewater, or if the cost of treating is prohibitive, then alternative sites should be considered. It is important to determine this at the earliest stage to avoid unnecessary costs. Site assessment will increasingly be required to provide fundamental engineering information to design remedial solutions to dysfunctional legacy wastewater treatment systems. Traditional means of assessment using trial pits and test holes are not appropriate in such circumstances. Proper soil sampling analysis and on-going monitoring of the water table, along with sampling of groundwater is required in order to design an appropriate sustainable and cost effective solution. Our Site Assessment process includes a 3D Topographical survey of the extents of the particular site. Further soil sampling to include valuable information for Civil & Structural Engineers in relation to foundation design can be carried out at the same time. The survey and foundation soil test results will save you money in planning your project.

5. When should a Site Assessment be carried out?

Site Assessment should be carried out at the earliest opportunity. If you intend building on your own land the assessment should be before you approach anyone to create drawings or make a planning application. Ideally it should be done before you purchase a site. It would be pragmatic for the vendor to have the Site Assessment available prior to advertising a site. The assessment is site specific. The actual design proposal will be based on the ultimate design of house but will be founded in the Site Assessment. Furthermore, in some circumstances the location of a dwelling on a given site may be influenced by the requirement of the site to treat the wastewater. Therefore, issues such as location of dwelling, floor levels, location of well for drinking water, and access for maintenance form important considerations at the outset of the development planning process.

6. How do we carry out a Site Assessment?

Firstly, with Percol8.ie there is no need to hire a “digger” to excavate dangerous trial holes, which have to be left open for several days and then back-filled. We have a purpose built Percussion Drive Sampling Rig which takes undisturbed soil samples and forms percolation test holes. These soil samples are later analysed in accordance with BS. 5390: 1999. There are different stages to producing a valid Site Assessment. The first stage is a desk study. This is carried out before the Assessor visits the site. It is used to identify important information relating to the specific site. Expected soil type, bedrock type, surface and groundwater flow directions, archaeological issues, topography, County Development Plan’s, vulnerability categories, and adjacent wastewater treatment systems installed in the locality form part of this desk study which is used to inform the Assessor about the specific site.

The on-site process involves several procedures. The first involves a topographical survey of the complete site, identifying boundaries, existing ground levels related to a Temporary Bench Mark, locating any existing structures etc. The second stage involves geotechnical soil sampling using a Percussion Soil Sampling Rig. Undisturbed soil samples are taken and labelled. A pvc liner is installed in a strategically located monitoring well. This well is sealed and capped to facilitate future monitoring of the Water Table and seasonal variations. This well will also facilitate future sampling of groundwater to verify appropriate treatment by the system. Depending on the site, three to six percolation test wells are strategically located, at the appropriate level, in order to facilitate the verification of permeability results from soil sampling. We return to the site at a later date in order to record the level of the water table and to verify results obtained in the lab from analysis of the soil samples. An important benefit of the Percol8.ie assessment is that undisturbed soil samples are available for the Planning Authority if verification is required and both the water table level and percolation test holes remain available for the Local Authority to verify results. Furthermore, the strategically located monitoring well is intended for on-going future sampling of the groundwater to verify treatment of the wastewater. These are unique capabilities compared with traditional on-site wastewater treatment assessment. The soil samples are photographed and uniquely labelled. An appropriate section of soil sample is taken to the Laboratory for testing. The remaining samples are held by the Client for later inspection by the Local Authority if required. Following results from the sampling which is carried out in accordance with BS 5930: 1999 and takes a minimum prescribed time, the level of the water table is recorded and percolation is verified in the percolation test holes. The final report is then generated and a design proposal is included. The design proposal is based on the results from the various stages of the assessment.

7. What is Wastewater?

Put simply, would you drink it? If the answer is no, and if it’s not rain water, then it’s wastewater. Wastewater is any used water generated in your dwelling. Water originating from toilets, sinks, showers, baths, washing machines, dish washers, or food grinders is wastewater and requires treatment before re-entering surface water or groundwater. If these waters are not treated you are considered to be polluting and the policy is that the “polluter pays”. That means that you, the householder, will be held responsible. In any case, would you want to pollute you neighbours well or even your own? It’s much easier do this correctly from the start. Proper design and, most importantly, supervision during installation ensure this. It is a source of amazement the number of “Builders” who still do not know the correct plumbing arrangements for wastewater. If they still insist their way is correct ask them to provide you with indemnity insurance for this. There are horrendous costs associated with correcting these problems. Foot-paths and lawns usually have to be dug up in order to rectify these matters. The cost of doing it correctly the first day is insignificant when compared with the cost of solving problems.

8. What is a Wastewater Treatment System?

There is much confusion about some of the terms used. A dictionary definition of System is “an assembly of parts which form a whole”. In this case it involves everything from your toilet, sink, shower, bath etc., the connecting pipework, a septic tank or a packaged wastewater treatment plant/unit or an intermittent filter, any necessary pumps, distribution chambers, percolation area or polishing filters, including the soil in these and/or reed beds and even tertiary disinfection equipment if installed. A common mistake is to call a packaged wastewater treatment plant or unit a system. It is only one part of a system. On its own it would treat nothing unless it is connected to other parts of the system. Treating wastewater is a completely natural process. The best results occur when we engineer or facilitate the conditions for this natural process to operate. It is not rocket science. The secret to successful treatment is attention to detail in design and installation, followed by appropriate desludging and maintenance.

9. Septic Tank or Packaged Wastewater Treatment Unit/Plant?

In general, mankind cannot improve on nature. Put quite simply, wastewater treatment is a natural process. It is well recognised, and has been academically verified by research, that in the appropriate soil conditions, a septic tank and percolation is as good a method of treating wastewater as any other. A septic tank and percolation area is much less expensive to install and importantly, much less expensive to operate and maintain. With appropriate desludging a correctly designed septic tank and percolation can work for the lifetime of a home. There are some situations where a secondary and/or tertiary packaged treatment plant is appropriate and may be necessary. In the first instance it is our policy at Percol8.ie to investigate if the conditions are available, or if they can be engineered, so that a septic tank and percolation will provide for the wastewater treatment. If this is possible significant cost savings will accrue to our Client. We do not benefit from any particular result. We consider it our duty to propose the best outcome to our Client. Packaged systems generally require a constant power supply and contain pumps and/or mechanised parts. These will require servicing and ultimately replacement. Two fundamentally important points are correct design and correct installation. This does not need to imply extra or higher costs. In fact it is our experience that many people, who were inappropriately advised, wasted significant funds on unsuitable expensive systems which were incorrectly installed. We commit to proposing a system in the absolute best interest of our client. We have no agreements with manufacturers or suppliers of systems.

10. Who are our Clients?
  • Individuals intending to build a home in the countryside.
  • Architects, Engineers or agents making planning applications on behalf of clients. As part of the Site Assessment we include a topographical survey of the site in CAD and permission for its use by the planning agent for the benefit of the client. This facilitates a cost saving to the Agent and Client.
  • Individuals who are aware that their system is dysfunctional or polluting and wish to have a sustainable solution designed and costed.
  • Individuals who have been notified that their system is dysfunctional or polluting following a Local Authority Inspection.
  • Public Bodies, Local Authorities, Housing Agencies, with residential or commercial property using on-site wastewater treatment systems.
  • Private commercial enterprise with a requirement for on-site wastewater treatment.
  • Vendors of development sites.
  • Civil Engineering practices with a requirement for information gained from geotechnical soil sampling for foundation design.
11. What is BS 5930:1999?
British Standards Institution

A standard is an agreed way of doing something. Standards are knowledge and in this case when applied correctly will provide fundamental information about the capabilities of the soil on your site. BS. 5930: 1999 is the British standard for soil analysis. It deals with the investigation of sites for the purposes of assessing their suitability for construction and civil engineering. The methods of this standard provide Engineers with knowledge of the characteristics of a site that affect the design and construction.