Leachate Treatment for discharge to
Surface Water Discharges.
Many Enviros leachate treatment plants discharge to rivers and streams where 100% compliance is mandatory and is routinely achieved.
Our very first plant at Bryn Posteg 22 years ago was designed to comply with the requirements of the surface water discharge consent issued by the environmental regulator (at that time the National Rivers Authority).
That same plant provides testimony to the reliability of the our processes, as it with many others continues to work, with necessary equipment updates and replacement (of worn-out aerators and pump motors at the end of their economic lifetimes), and it continues to discharge to that watercourse.
In the UK discharge consents are issued on a site specific basis, and for a number of important water quality contaminants, a degree of flexibility is available within defined stringently applied limits, such that provided that for example dilution is available, some strengths required by the consent may be somewhat relaxed, This is of course, provided that the relaxed limit will not cause an environmental impact.
This degree of flexibility is not permitted by the regulating authorities in many countries. Even within the EU (where such interpretation is perfectly permissible within the regulations), many countries enforce national consent limits within which there is often no flexibility once the category of discharge is agreed.
However, a degree of flexibility in the discharge consents issued by any regulator is essential if the principle of BATNEEC (Best Available Technique Not Entailing Excessive Cost), is to be applied (as is also permitted within the IPPC Regulations).
One clear example where a “national standard” can result in excessive cost, (where a treatment cost would not benefit the environment), is that of a strict salinity limit set in a national standard, where say a small leachate treatment plant discharges in to a large river close to where the river discharges into a saline estuary, and the lowest flow of the river can be as large as 1000 times the discharge flow.
The presence of a discharge possessing a salinity slightly above the national standard would not, in this example, cause any environmental impact at all. In fact, it would be undetectable within 2 metres of the discharge point where it would fall into the river and be swept away immediately.
The cost of removing the salinity may well double (or more) the price of the leachate treatment plant, and while it may be essential for a discharge to a small river in midsummer at a different location, where much of that river’s flow is being used for irrigation, it would make no sense to remove salinity in the example we have just described.
We have found, nevertheless, that even in countries where prescribed national standards apply, Enviros has on occasions been able to negotiate the one-off relaxation to certain surface water discharge consent requirements, by the presentation of a rigourously made scientific case.
Call, or contact, Howard Robinson at the telephone number, or email address, below.
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