Introduction

Illegal dumping or unauthorized dumping is the disposal of waste at private or public places around the city which is not permitted as per law (Corbyn Lisa, 2008).  With the enactment of the MSW2000M&H rules, most cities in India have begun to shift to regulated USW collection and centralized processing systems.  Each urban unit has identified at least one site where the USW collected from the city is being landfilled or otherwise processed to compost, recyclables and a certain fraction as landfillable inerts.  Earlier a large fraction of USW remained on city streets to be partially dried and partially consumed by stray animals.  This partially reduced the weight.  Sometimes such partially dry wastes were burnt in the bin or at the dumpsite to make way for fresh wastes to be added.  As these practices have been stopped and contracts issued to various garbage contractors to lift such garbage from community bins to designated USW processing sites.  As a result there is a gradual shift from the earlier haphazard dumping on road sides to an increased level of wastes sent to and processed by waste treatment facilities and landfilling. Yet this slow transition is still accompanied by several kinds of leakages and spillages, wherein a certain fraction of total USW is even now dumped at a few of the less visible locations in order to save transportation costs or to cover up delayed arrival at the wastes processing site – processing sites close operations at sunset and trucks filled with USW need to wait till 0900 or 1000hrs when the processing sites open their activities in the morning.  To overcome such waits, USW is dumped by these transporters in remote locations just outside city limits.  Such small and continuously changing dumpsites are sufficiently important because of the plastic and recalcitrant waste components that firstly spread by wind and water and become anaesthetic.  Second, wastes attract the next potential dumping instance and more of the wastes are dumped nearby in the next instance of illegal dumping. Waste materials dumped in this fashion generally include construction and household wastes that can be treated and recycled to be reused as resources.  

Everyday Bangalore generates around 3600t of urban waste and 55% of this waste is contributed by residential houses.  It is estimated that nearly 90% of the fresh USW generated in Bangalore is fermentable and can have a high C-footprint if not handled adequately (Chanakya and Sharatchandra, 2005). Bangalore city employs a quasi centralized collection system achieving a 75-90% of waste collection efficiency, which is satisfactory and keeps the city clean (Chanakya et al., 2009).  This means primary collection system functions with reasonable efficiency in terms of time of collection and the extent of collection.  The wastes collected are meant to be transported immediately to the designated waste processing sites.  However, for example when small tipper autos collect one round of USW from households they are expected to tip the collected wastes to the next larger vehicle or a large bin.  In the event such a bin is not free or delayed in its arrival at the designated point, the tipper autos or handcarts dump the collected wastes from the first round at this site and move on to the next round of collection.  Such an act renders small waste dumps within the city limits but is ephemeral – they are cleared within a few hours.  Yet they constitute small temporary dumps.  It is believed that when the system efficiency improves such small dumps would be eliminated.  However, the larger and randomly carried out dumps that occur on the outskirts of the city remain for a long time and is the concern of this study.

There are three designated waste treatment and disposal facilities in Bangalore; Mandur, Mavallipura and Karnataka Compost Development Corporation (KCDC).  Presently KCDC has been closed and not working. During the early stages, when the city produced about 650tpd (1988), about 100tpd of market wastes were taken back to villages for direct application on land and another 150tpd was handled by KCDC.  The rest, comprising a large fraction of decomposable was ‘open dumped’ along various arterial roads leading out the city (Rajabapaiah, 1988).  This trend has continued till about 1999-2000 and the proportion of wastes carried to these arterial roads were approximately same (TIDE, 2000; Chanakya and Sharatchandra, 2005; Lakshmikantha, 2006).  There are social and technical limitations which lead to this problem.  Primary measures like fine for illegal dumping and transport vehicle with Global Positioning System (GPS) were taken up in 2010 to avoid this kind of dumping, but failed to control it.  Finding the location and quantification of unauthorized dumps is still a difficult task because these occur at random and since Bangalore USW has a very large decomposable fraction, much of it would be decomposed in a few weeks leaving behind predominantly the non-decomposable fraction that gradually spreads and becomes unaesthetic.  Most often the size of this dump could be that equal the one caused by tipping the contents of a single truck (c.5t) and this cannot be detected easily.   However, when more than 2-3 truck loads are tipped, the sizes become cognizable both visually as well as from remote sensing techniques.  In few locations in Japan satellite images (Quickbird, 0.61m resolution) were used to find the locations of unauthorized dumping (Yonezawa, 2009).  However, most studies have failed to quantify waste which goes for open dumping.  As discussed above there are usually two categories of open dumping - one that is temporary, ephemeral and keeps on changing in locations while the other is larger and frequented many times and persists longer. Obviously the one time event type of dumping is difficult to quantify.  However, there is potential to quantify the latter 

Much of the illegal dumping that is discussed above occurs outside the limits of the city on generally lesser used land (land that is not under cultivation but is left unattended for a long time).  Mush of the waste at this stage is carried by trucks that require a motorable road and in addition that can take the kind of weight of a truck.  This significantly reduces the points where wastes can be dumped to places along temporary and asphalted roads on the outskirts of the city.  Such roads are few in number and therefore the extent of survey to be carried out is also small.  This article focuses on the method to find the location and to determine the volume of waste disposed illegally.  A second problem of undertaking a conventional survey by a few investigators is the rate of degradation of components of USW which makes it difficult to determine the rate of dumping.  In order to overcome this difficulty it is necessary to carry out a large volume survey with a large number of semi-trained volunteers driving motor-cycles and scooters around these poorly motorable roads and tracks.  Here, in order to find the locations of dumpsites intense field survey was conducted in all the outer part of the city.  The study site, the entire city and its outskirts has been divided city into grids and almost all grids were covered in field survey. This provided the required data to determine the causes of unauthorized dumping in addition to identifying all the dump sites.