Leachate Treatment in India

Image by Sustainable sanitation via Flickr

The continuing poor management of landfills in India is a disgrace, so it is no surprise that although we have seen evidence that there is growing interest in the scientific application of good leachate treatment practice in India, it would seldom be possible to apply it, given the unscientific way in which so called "landfills" (dumps?) are currently engineered and managed.

The following is an extract from an article on 24 April of this year (this month) on which I rest my case, since it is based upon the wealthy capital city of the nation:

Delhi government calls its three garbage dumps at Ghazipur, Okhla and Bhalswa landfills. In reality, they are far from what a landfill should be. These are monstrous trash mountains, including hazardous waste, leaching out toxic liquids and emanating noxious fumes. Thousands of scavenging birds swarm over them as they grow larger every day.

The situation could have been different had the corporations given more thought to managing them. Ask any waste picker who scavenges on these dump yards about why this waste could have been a treasure...
...there are hundreds of waste pickers who pick up whatever they can without using masks, gloves or any other protection. Some even tie a magnet to a long stick to pull up metal objects.
 Credits: Capital dumps a fortune at its landfills - Times of India
 

In my opinion the provision of proper waste disposal facilities should be on the very top of the agenda as any nation industrializes and becomes more wealthy. If India cannot devote just a small amount of it additional wealth which has been accruing at a historically uniquely rapid rate for more than the last ten years, then it is a failing state.

To deny pickers the ability to make a living can be an evil, but so many other nations (including many of lesser wealth) have found a way to recycle waste in a way that provides jobs for the local community without recourse to the life threatening and certainly extremely unhealthy practice of "picking".



At the same time, it has been possible to provide reliable leachate treatment and disposal once the landfills are properly managed and built in accordance with good sanitary landfill practices as have been acheived in the majority of nations around the world.

Providing successful leachate treatment plant designs in India, for the old existing dumps is an impossible task. That is because the prediction of leachate quality is rendered from scientific capability to a matter of guesswork by a lack of data and controls, and this is made even worse by India's monsoon climate which means that any leachate treatment plant needs to be able to run at almost no flow in the dry periods and very quickly at the start of each monsoon be able to treat it's maximum design flows.

As the most effective, and lowest cost forms of leachate treatment rely on biological processes and these cannot be quickly switched on therein lies another problem for leachate treatment in India.

Then finally, any leachate treatment plant designer for Indian landfills will discover that the water quality that the Indian government's own rules require the leachate to be treated to, are as strict, or require higher water quality after treatment, than even many authorities require in the wealthiest industrialized nations.

Unfortunately, waste management and especially landfill methods don't seem to get any better in India, despite increased wealth. They won't be able to do so, until the central Indian government revises the rules and makes them realistic, less strict but much better value for money, and appropriate to what the municipalities can afford to spend.

The 80/20 rule should be adopted, at least to start with for all future leachate treatment projects because by reducing the specifications for final water quality and using innovative solutions Indian landfill operators should be looking to spend 20% of the cost they are being quoted currently for leachate treatment plants for 80% of the treatment quality, and that treated quality would be good enough for the local rivers for the health of the rivers to which the leachate plants discharge, and for those using the water from them.

Report on Leachate Management Solutions Offered in Recent Articles

Let's start this article about leachate management by going back to basics and defining what we mean by the term leachate, and the way I suggest that we do that is to refer to the recent post from ET Environmental which gives a clear definition for any one reading this page who is unsure:

When liquid passes through trash material, such as in a landfill, “leachate” is generated. Rainwater is the largest contributing factor of leachate, but natural decomposition and discarded chemicals also contribute Credits: Leachate: What is it? - ET Environmental

Leachate management is the planned operation of landfill sites in such a way as to avoid the production of leachate as far as practicable, and to drain, collect, treat as necessary, and dispose responsibly of the leachate which is not prevented.

So, now that leachate has been defined we look further around the web and find that there is a discussion of managing landfill leachate seepages (often called "breakouts" in the waste industry), below the final capping membrane at Waste360.com, as follows:

Leachate seeping out of landfill slopes is a common occurrence. Operators struggle to address leachate seeps and manage liquids reaching landfill boundaries. During dry spells, it takes less effort on the part of operators to control liquids on landfill surfaces, and seeps are therefore more manageable. But during periods with frequent storm events or in high-precipitation regions, landfill operators must work constantly on slopes to stop seeps or devise means to control liquids when they do ...Credits: The Use of Leachate Toe Drain Systems Can Deal with Seeps After ...

The authors must be referring to landfills in very wet climates, as such seeps should not normally occur when landfill cells are covered rapidly after filling to avoid the potential for vermin to breed, and for odor production, as required by sanitary landfill procedures (US), or the EU Landfill Directives and related regulations.

Rather than build temporary toe drain systems at substantial cost it is normally recognized to be better to plan the cellular construction of a landfill for smaller cells and to bring those cells up to completion at the surface of the landfill as quickly as possible. Capping and restoration of areas of the landfill prevents further rainfall ingress and that not only allows a permanent landfill gas extraction system to be installed as soon as possible for maximum landfill gas capture, but minimizes leachate production. That's the best form of leachate management there is, namely - make sure that the landfill produces as little as possible!

While browsing for leachate management solutions, we found our own website back in 2011/12, which contains some articles on the subject, namely:

The starting point in any discussion about UK/ EU leachate management techniques is to begin by stating the overriding rule upon which all landfills are operated, in compliance with the EU Landfill Directive. That is that as far ... Credits: Leachate Management Techniques | The Leachate Expert Website

However, perhaps the best page about leachate management is to be found on the leachate Wikipedia page.

Recent Leachate Problems And How To Cure Leachate Breakouts

There have recently been a number of articles on the web that help with solving many of the recent leachate problems which have been publicised.

The types of problems which landfill operators are experiencing have been exemplified in the following articles already this year:

1. Leachate Produced that must be Treated Before Disposal

The landfill site in Memelhakha in Thimphu has started producing leachate. Leachate ,the liquid produced by waste, is said to be poisonous as it contains toxic chemicals. Leachate can also contaminate the ground water and ... 

Credits: Memelhakha landfill starts producing toxic leachate | BBS

2. Leachate which Escapes a Watercourse Before It Can Be Collected and Treated for Safe Disposal

The following was reported on the Department of Environmental Quality's Riverbend Landfill website,  but don't bother looking online for information about the January leachate leak -- that information is no longer there.

Leachate release — On February 10, 2014, landfill personnel observed leachate escaping from the landfill’s northern boundary. Waste Management reported that this leachate reached a creek approximately 300 feet from the landfill.
This leachate was primarily liquid that had collected in the landfill’s gas extraction wells. To keep the extraction wells working properly, this leachate is routinely pumped from the wells to three 21,000-gallon storage tanks near the north side of the landfill. This leachate is kept separate from the majority of the landfill’s leachate, which is pumped to the onsite leachate pond.
This reason for this separation is that leachate associated with the gas extraction wells is more concentrated than the rest of the landfill leachate, and is therefore sent to a different offsite facility for treatment and disposal.
Tanker trucks that routinely haul this leachate to an offsite treatment plant were unable to get to the site because of heavy snow and icy roads.Flow of leachate from the landfill to the tanks was stopped because the tanks were full.
This is believed to be the reason leachate began seeping from the landfill. To prevent this problem in the future, Waste Management has connected these tanks to the pipeline leading to the onsite leachate storage pond.

 Credits: January Leachate Leak? - Stop The Dump Coalition - Blogger

3. Leachate Which Escapes Into the Ground and Creates a "Plume" of Pollution Below the Ground

The investigation was carried out to ascertain leachate plume generation and migration and its impact on the surrounding soil and the groundwater. 2D electrical resistivity imaging using Wenner array was used to delineate ... 

Credits: 2D Electrical Imaging Surveys for Leachate Plume Migration at an ...

Solutions And How To Cure Leachate Breakouts

The breakout of leachate both to the ground around and below a landfill can be prevented by good landfill lining design, and high quality construction of the liner with a high degree of construction quality control, preferably by an accredited independent organisation.

Find out more at http://leachate.eu