Faecal Sludge Natural Treatment plant (FSNTP) at Ponnampatti Town Panchayat Trichy District, Tamil Nadu 1 Introduction Ponnampatti Town Panchayat is located 64 km from Trichy on the Trichy-Madurai National Highway (NH-47) in Marungapuri Block of Trichy District, inclusive of Thuvarankurichi Town. In view of the very innovative and pioneering initiatives in the field of Solid Waste Management, sanitation, Faecal Sludge Management, Drinking Water Supply, continuous Sustained awareness programme, The Ponnampatti Town Panchayat was adjudged as the Best Town Panchayat by Tamil Nadu Government in 2017. It is fast developing as a Sanitation destination in the State and Country. Tamil Nadu Chief Minister Edapadi Palanisamy hand over the Award to Mr. Shakul Ameed, E.O, in the presence of Ms. Girija Vaithiyanathan, IAS., Chief Secretary. 1 The PTP has a population of about 18,000 and is divided into 15 wards spread over an area of 10.83 km2. The area of the Resource Recovery Park is 2 acres (0.81 ha) and was established on a rocky rugged elevated space, is 3km from the Office. Total number of households is 4,120. Total administrative staff is 12 and has 48 field staff. It has two higher secondary schools, one matriculation school and 9 Panchayat Primary schools. 1. Sanitation Background in the Country: Flush Toilets linked to Septic Tanks or Leach Pits are the most popular types of toilets in unsewered area in India irrespective of whether it is a Metro, City, Municipality or a Panchayat. Use of Septic Tanks, an anaerobic baffled reactor as per theory, results in generation of sludge settling at the bottom which needs to be removed every -5 years to keep the Septic Tank functional without problems. The sludge from the Septic Tank generally referred to as Septage, in theory will be digested sludge. However, most of the Septic Tanks are not designed or constructed properly as per the stipulations in the BIS Code of IS 2470 Part 1. This makes the safe treatment and disposal of septage still more challenging a task since the material available by de-sludgng an improper Septic Tank will be a mixture of partially digested and undigested sludge along with some digested material and thus having characteristics resembling raw sewage than septage. The faecal sludge removed from lakhs of houses in the Country are transported for disposal in a most unhygienic manner by faecal sludge tankers and are emptied in river, river beds, canal bunds and on deserted roads. (See photo) This practice contaminates the surface water, underground water and air. After knowing the major hygienic problems caused by the practice the Government of India formulated a Septage and Faecal Sludge Guidelines and ask the State Governments a formulate the Necessary Regulatory Acts. Tamil Nadu was the first State in the Country to come out with the septage management policy and formed the guidelines. 2 As per the act all the new households in the State will be granted approval for the construction only if the plan has a sanitary toilet as per the Public Health Act of the State. The approval for the use of the house after construction will be granted only after the house was provided a Septic tank as per the plans. The Town planning Act also was suitably amended. However, almost all urban local bodies were rather indifference in implementation of the Act. Naturally disposal of septic tank faecal sludge is standing is major health hazards a very large number of cities and towns in the Country. 2. Options for Treatment and Disposal/Reuse of Septage/Faecal Sludge 3.1. Background 2.1.1 Faecal sludge is often a misunderstood term. Even those in positions of authority use the term faecal sludge and excreta interchangeably. While excreta is the raw matter discharged from a toilet, the faecal sludge is the material which has undergone a certain amount of biological degradation in one or other means of collection and processing. In an ideal condition, the faecal sludge will be in fully processed condition and hence in a stabilized form. Due to this confusion, some among the very few initiatives in India to set up and operate faecal sludge treatments adopted the approach focusing on perceiving FS more are sewage while others approach starting from handling digested FS. While there is very little work done on analysing the potential of use of treated sludge alone or in combination with other materials as manure, considerable amount of time, energy and funds are spent to focusing on the effluents from the sludge processing systems. Over and above this, FS is perceived as a problem to be solved and not a resource to be utilised. 2.1.2 The type of toilet used has a significant impact on the characteristics of the sludge generated. For urine diverting toilets, there is practically no sludge with just the completely digested material in powder form as the end result. For flush toilets, the main options are Septic Tanks and Leach Pits for in situ treatment. In the case of the sludge from the pit of a Twin Leach Pit system is already fully digested material which can be used directly as manure without any concerns from the health angle. However, they may need to be removed by pumping which in turn warrants dilution of the same by addition of water. Either way, the material removed need not be 3 considered as sewage but the treatment, disposal/reuse method starts from dewatering rather than any pre – processing. Septic Tank sludge contains a mixture of fully digested sludge, partially digested material and a small quantity of fresh excreta. 2.1.3 Where Septic Tanks or Leach Pits are connected to a flush toilet, the feed determines the characteristics. The possibilities include all kind of discharges which include kitchen effluent, laundry effluent, bath water and toilet discharges, excreta alone or a combination of two or three streams mentioned. However, in India, we have a unique situation in which the tank which goes by the name Septic Tank, could be a huge tank with or without lining which effectively is an underground storage tank which if lined, may require frequent emptying and if unlined may need emptying only very rarely. In the case of a lined tank which requires frequent emptying, the material pumped out, is effectively equivalent to raw sewage. While it is acceptable that the material so removed is treated and disposed or used safely, it would be far more logical to modify such systems to make them good in situ treatment systems. Such initiatives had been made in India with good success rates and methodologies to convert such systems that too will be an objective of this guide. 2.1.4 In a system with Twin leach Pits or Urine Diverting Dehydration Toilets, the material emptied is almost safe to handle. However, in a Septic Tank, the situation is somewhat different since the contents could be a mixture fresh excreta, partially digested excreta and fully digested sludge. Handling of septic sludge constitutes a serious health risk, since people handling these materials may be exposed directly to pathogens. From human health risk a basic distinction should made between sludges, which, upon collection, are still relatively fresh or contain a fair amount of recently deposited excreta and sludges which have been retained in on-plot pits or vaults for months or years and are virtually free of pathogens. Black water, constitute high-risk material and exhibits characteristics similar to sludges collected at short intervals e.g. from public toilets with only holding tanks rather than a processing cum disposal system.. Special care is therefore necessary to prevent accidental contact and spills during 4 emptying of toilet pits or vaults by vacuum trucks, where varying amounts of water or wastewater are collected alongside the accumulated solids. 2.1.5 In most of India, disposal of faecal sludge has been a major issue but not addressed seriously by the authorities. In certain areas, there are common Sewage Treatment Plants (STP) which anyway have facility for treatment and safe disposal of sludge. Most of the STPs in India accept Septage/faecal sludge for a fee. Field observations, however, indicate that this facility is rarely being utilised by the public or local bodies. The reasons could be one or more of the following ❖ Distance of the STP from the point of collection ❖ The fee charged by the operators of the STP ❖ Lack of awareness on the side of operators of STP or the transporters of faecal sludge or even both ❖ Absence of legally binding guidelines of collection, transportation, treatment and disposal/reuse of faecal sludge. 2.1.6 Surprisingly no proper inventory has been made concerning quantities of the faecal sludge that needs to be disposed, or the type of sludge (quality) that needs to be treated and disposed. In the latter case a distinction should be made between fresh and old sludge, and septic tanks containing only toilet water (black water) or those containing toilet and wash water (black and grey water) and, possibly, even rain water. 2.1.7 Since the raw faecal sludge often has partially digested or even fresh excreta in it, many FSTPs adopt a system similar to Sewage Treatment Plants (STP) using one or the other aerobic systems for sewage treatment, followed by dewatering of the aerobic sludge obtained from the Sewage Treatment Plants. In cases when the faecal sludge is having a high solids content, the same is often diluted with water first in order to process in the STPs. 5 Prima facie, it looks counterproductive since dewatering should be, in theory, the first step for processing the faecal sludge.