CHAPTER VII

7.19 ASSIMILATIVE CAPACITY STUDIES OF DIFFERENT RIVERS.

Wastewater of industrial and domestic origin is ultimately discharged to the rivers. The natural assimilation capacity can take care of these pollutant to some extent though discharge on excess amount may cause upset of such system. Capacity of assimilation of pollutants generally varies river to river. If capacity of assimilation can be ascertained the fate of the pollutants can be predicted. Keeping this in view The study has been undertaken to assess the fate of pollutants after discharge. Different types of carbohydrates, metals, urea, EDTA etc were added to 40 litres. of river water and the water was aerated to keep the particulate matter in suspension to simulate the riverine condition. The samples were collected 2 hourly intervals. The analytical results obtained in this study revealed that quantity added was not adequate to distinguish the changes by the methodology adopted. Overall declined trend was observed for BOD, COD, Alkalinity, and Faecal Coliform (FC) and inclined trend was observed for pH, nitrate and total Coliform. Further study was conducted increasing the quantity of chemicals for Damodar and Hugli river with limited parameter. The level of decreasing of COD, BOD, FC, etc was varying depending on the substances added and the concentration of suspended solids in river water. The metals like Iron, Zinc and Manganese were removed sharply in river Hugli due to co-precipitation (Table 7.24). Though these inferences can not be drawn firmly with one round of monitoring, but it may be mentioned that assimilation capacity of different rivers can be ascertained covering other rivers with number of trials.

7.20 POLLUTION POTENTIAL OF LEACHATES FROM SOLID WASTE & BIO-MEDICAL WASTE DUMP SITES AT DHAPA AND BANTALA IN KOLKATA

Dumping of Solid Waste leads to soil and groundwater pollution. To study the Pollution potential of leachates from solid waste an active dumping site at Dhapa and Bantala area was selected. Lysimeters of about 3.0 m was installed at both the sites.

At regular interval leachates were collected for assessment of relevant physical, chemical and biological properties from 3 m depth of the active dump site. The results indicate the microbial contamination is very high both in soil and leachate along with the presence of high content of toxic metals like manganese, iron, lead, zinc, chromium (Table 7.25).

TC - Total Coliform ; ECLO -Escherichia Coli like Organisms FCLO -Faecal Coli like Organisms SLO - Salmonella like Organisms SHLO - Shigella like Organisms VLO - Vibrio like Organism SFLO - Streptococcus like organisms PLO - Pseudo monas like Organisms

The ground water quality was monitored at old dump site at both in Dhapa and Bantala area in some important places like ITC Group Hotel Sonar Bangla , Science City and P.C.Chandra Site, CMC Village - a Slum Settlement. The minimum depth of Well was 45 m at CMC Village site and maximum was 165 m at science City.

The Water quality monitored may be corroborated with the findings of leachate and soil. The Ground water Conductivity ranged from 1772 to 1968 µs/cm whereas TSS varied from 2 to 33 mg/l. The concentration of SO42-, PO43-, Na+, K+, Ca2+, Mg2+, NO3- Cl- are above the critical limit given by WHO. Alkalinity and hardness ranged from 324.5 to 385.0 mg/l and 535 to 644 mg/l respectively which is much higher than the critical limit of safe drinking water. The heavy metal content in these ground water was found in low concentration but the alarming concentration of different microbes (Tables 7.26 & 7.27) in these area ground water is a cause of serious concern.

7.21 ASSESSMENT OF EFFICIENCY OF SEWAGE FED PONDS WITH RESPECT TO CONVENTIONAL SEWAGE TREATMENT PLANT

The conventional sewage treatment processes such as activated sludge and trickling filters are quite efficient for removal of pollutants from wastewater but these hardly remove 20-25 percent of inorganic nitrogenous and phosphates present in sewage. These nutrients still remaining in treated water, play important roles causing algal blooms and thus deteriorating water quality in the receiving bodies of water. In order to get suitable quality of water, tertiary treatment is required and this makes conventional process more expensive and unattractive whereas sewage has long been considered as an important source of nutrients and organic matter for agriculture and aquaculture. Use of sewage for fish culture is being practiced since long. Aquatic plants and micro-organisms grown in those sewage fed ponds help to maintain the purity of water. Therefore adoption of pisciculture utilising sewage in a very scientific manner may be one of the best options to minimise the pollution load in wastewater canal. Also aquaculture is not only a potential system of sewage disposal but also offers attractive economic and social benefits.

Sewage water is extensively used in West Bengal for fish culture. The large quantity of waste water from Kolkata metropolitan is carried to Kulti estuary through a very long dry weather - storm water flow combined canals. From these canals sewage is utilised into sewage fed fish ponds on the eastern fringe of city. The area covered by sewage fed fisheries was more than 11000 acres in 1945 with a production of 3.39 Quintal per acre. With the rapid urbanisation the most of the area has been reclaimed and the current sewage fed fisheries area has declined to less than 8000 acres. However, production per acre has increased to 10 quintals per acre. Currently 148 units of such fisheries are reportedly operating in Eastern Kolkata.

Considering the above, a study was undertaken to assess the status of sewage fed ponds located close to Kolkata city and its level of efficiency with respect to conventional sewage treatment system. In this study emphasis was given on characterisation of water and sediment in different ponds to assess the status of pond ecosystem, suitability of fish growth and the efficiency of removal of pollutants. The samples were collected from different ponds at different seasons to study the seasonal and pond to pond variation. For comparison of efficiency, average values at inlet and outlet of the ponds are presented in Table 7.28.

The result obtained from different STPs in West Bengal were incorporated in Table 7.29 to compare the efficiency of conventional treatment with sewage fed pond.

Based on the data, it may be mentioned that remarkable reduction was achieved for all the parameters generally considered as criteria parameters in both the system however sewage load in STP was higher but at the same time , it was not ascertained the optimum load of sewage that could be utilised by sewage fed pond. Sometimes in sewage fed ponds inlet BOD and COD were higher due to presence of algae. To study the impact of algae on BOD/COD values, measurement were carried out in filtered and unfiltered samples. The strong correlationship was observed between BOD/COD and TSS. The ratio of BOD/COD both filtered and unfiltered are presented in Table 7.30 to evaluate the performance and cross checking of data.

F- Filtered, UF- Unfiltered

The reduction of bacterial load is significantly high in sewage fed ponds as shown in Table 7.31. Though reduction of pollutants in sewage fed ponds was not at par in all the cases but cost wise sewage fed ponds is more attractive.

Texture and metal content of sediment were incorporated assess the holding capacity of metals and their interaction with pond water (Table 7.32).

Zooplankton, phytoplankton and chlorophyll was measured and incorporated in the Table 7.33 to asses the availability for fish and identify the groups of Zooplankton and phytoplankton to asses the suitability of food to the fishes.

The study revealed that overall management of sewage fed ponds not very scientific but still performance of sewage fed pond in these situation indicated tremendous potential in treating sewage water with valuable return. Further improvement may be possible if following aspects will be taken into account :

Ø Dosing of sewage.

Ø Prevention of addition toxic substances.

Ø Composite fish culture.

Ø Quality fish fry/finger links.

Ø Maintenance of water level.

Ø Regular harvesting of fish.

Ø Maintenance of fish food.

Ø Removal of excess mud on the bottom.

7.22 STUDY ON STATUS OF SEWAGE TREATMENT PLANTS IN GANGA BASIN

The major source of organic pollution in fresh water bodies is sewage. In India, all the cities and towns did not have sewage treatment facilities. Untreated or improperly treated human wastes disposed into aquatic resources from where the downstream city’s water requirements are drawn, constitute a big public health hazard in terms of their potential for spreading water borne diseases.

As per the latest estimate out of 22,900 Mld of wastewater generated, only about 5900 Mld (26%) is treated before letting out. The rest i.e., 17000 Mld is disposed of untreated. Twenty-seven cities have only primary treatment facilities and forty-nine have primary and secondary treatment facilities. The level of treatment available in cities with existing treatment plant varies from 2.5% to 89% of the sewage generated.

The Ganga is the largest and the most important river of India. The catchment area of the river Ganga in India is 861,404, covering 26.2 percent area of India’s total geographical area. The watershed of river Ganga spread over ten States of India, namely: Uttaranchal, Uttar Pradesh, Bihar, Jharkhand, West Bengal, Himachal Pradesh, Rajasthan, Haryana, Madhya Pradesh and Delhi.

Urban population consisting of Class I Cities and Class II Towns in the Ganga basin is 57 million (as per 1991) which is projected to be over 72 million in 2002. There are 101 Class I cities and 122 Class II towns in the basin. The recent survey of Class I and Class II cities indicated that about 8250 mld of wastewater is generated in the Ganga basin out of which treatment facilities are available only for 3500 mld of wastewater . Out of 3500 mld treatment capacity, 880 mld is created under the Ganga Action Plan, 720 mld under the Yamuna Action Plan and about 2189 mld is created by Govt. of Delhi for restoration of water quality of river Yamuna. The treatment facilities at 48 additional towns along the Ganga and 23 towns on its tributaries/sub-tributaries are being created under Ganga Action Plan Phase-II and National River Action Plan. It is expected that after completion of these plans, an additional capacity of about 1500 mld will be created. However, still there will be a large gap between the wastewater generation ( 8250 mld) and treatment capacity (3500 mld) (Table 7.34, 7.35 and 7.36).

Table 7.36 Summary of Sewage Generation Treatment and Disposal in the Ganga Basin

(i)Sewage Generation

7.23 sewage treatment status in the yamuna sub-basin

Delhi generates about 3600 mld of wastewater. Out of which treatment facility is available for only 2109 mld. Plant-wise sewage treatment capacity is provided in Table 7.37. It is observed that there is continuous efforts by the Govt. of National Capital Territory of Delhi to augment the treatment capacity. However, the exponential population growth is nullifying the results. The gap between sewage generation and its treatment is continuously widening inspite of the efforts of the authorities and monitoring of the Hon’ble Supreme Court.

The Cities and Towns discharging municipal wastewater in the River Yamuna in Haryana and Uttar Pradesh are taken up under Yamuna Action Plan. There are 12 Towns in Haryana and 8 Towns in Uttar Pradesh considered for setting up of sewage treatment plants.Two sewage treatment plants in Delhi also constructed under this plan at Sen Nursing Home Drain and Delhi Gate Drain with a design capacity of 10 Mld each. Under the plan 34 STP’s are commissioned with a treatment capacity of 743.25 Mld. The deatails of STP’s in each town, capacity and the type of sewage treatment plant is presented in Tables 7.38 & 7.39.

7.24 Treatment Technology adopted under Ganga Action Plan

The STPs were either renovated or constructed to treat the domestic sewage by adopting treatment technologies such as low cost waste stabilisation ponds, conventional Activated Sludge Process (ASP) Trickling Filter (TF) and Upflow Anaerobic Sludge Blanket (UASB) treatment systems. The details are provided in Table 7.40.

· Out of 35 STPs planned under GAP Phase I ( 3 STPs in Uttaranchal, 10 STPs in UP, 7 STPs in Bihar, and 15 STPs in West Bengal), 32 STPs are commissioned and 29 STPs were found functioning.

· Adequate fund allocation for O&M of STPs is not provided particularly in Bihar and U.P.

· A number of sewage treatment plants are under loaded e.g. Jajmau Kanpur, DLW Varanasi, Naini Allahabad while some other are over loaded e.g. Dinapur and Bhagwanpur at Varanasi.

· Many treatment plants need upgradation e.g. all the STPs of Bihar, Swargashram at Rishikesh, Kankhal Haridwar, Jajmau Bhatpra E Titagarh, Panihati.

· Out of 1345 mld of sewage joining the Ganga as estimated during 1985, the STPs were planned for only 875 mld. Since then, the volume of sewage has significantly increased.

· In Bihar, the treatment plants at Karmali Chak (Patna), and Munger are yet to be constructed. Similarly STP at Chapra and Bhagalpurare under-designed as their capacity is 2 MLD & 11 MLD against 8.74 and 28 MLD respectively. The Chapra STP is not receiving the sewage, as it is located far away ( 5 km) and there is siltation in the drain which is supposed to carry the sewage through gravity flow.

· None of the STPs has obtained consent from the concerned State Pollution Control Boards, although it is obligatory under the Water Act, 1974.

· Inadequacy of trained personal for O&M work is a major shortcoming.

· Non- availability of uninterrupted power is another problem at most of the places. Since the STPs are biological in nature, their continuous operation is must in order to maintain the biological growth at activated level.

· In most of the cities/towns included in GAP, is proper sewerage system does not exist and the sewage flows in open drains causing scenic and odour probloem. In rainy season, the run-off water generally mixes with sewage. Since the diversion of drains through pumping is taking care of only dry weather flow, during rainy season it cannot pump the additional load of run-off water. Thus, such interception will not be effective in controlling pollution of the river during rainy season.

· In many cities, the sewage is not reaching the STPs due to non- existence or non-functioning of sewage transport system.

· There are 21 towns under Yamuna action plan, 3 under Gomti action plan and 12 under Damodar action plan, 3 under Betwa action plan, 3 under Chambal action plan and one each under river Shipra and khan

· There are 223 cities/ towns (Municipalities/Corporation) generating significant amount of sewage in the Ganga basin. These cities/ towns generate about 8250 mld (million litre per day) of wastewater, out of which about 2460 mld is directly discharged into the Ganga river, about 4570 mld is discharged into its tributaries or sub- tributaries and about 1220 mld is disposed on land or in low- lying areas

· Out of 8250 mld of wastewater generated in the Ganga basin, the treatment facilities are available only for 3500 mld of wastewater (town-wise) treatment capacity is provided. Out of 3500 mld treatment capacity, 880 mld is created under the Ganga Action Plan, 720 mld is created under the Yamuna Action Plan by NRCD, MoEF Govt of India and about 2189 mld treatment capacity is created by the Govt. of Delhi for restoration of water quality in Yamuna river

· The treatment facilities at 48 additional towns along the Ganga and 23 towns on its tributaries/ sub- tributaries are being created under GAP Phase-II and National River Action Plan. It is expected that after completion of these plans, an additional capacity of about 1500 mld will be created. However, still there will be a large gap between the wastewater generation (8250 mld) and treatment capacity (3500 mld).

7.25 MONITORING OF GROUND WATER QUALITY AROUND SOLID WASTE DISPOSAL SITES IN DELHI

Delhi is one of the largest Municipal solid Wastes (MSW) generating cities in India. The quantity of wastes is nearly 7000 metric tonnes per day. These wastes are disposed mainly on land at three Land Fill Sites (LFS), namely Ghazipur (East), Okhla (South) and Bhalswa (North). These wastes include mainly organic materials (60%) obtained from various sources like domestic, vegetable markets, hotels, commercial areas etc. In addition, these LFS receive debris of building materials, drains sludge. Sediments etc. The solid wastes are being filled in the solid waste disposal sites for the nearly past 15 years. These sites are not having any lined materials for avoiding percolation of leachate from the solids. With the result there is an ample possibility of contamination of groundwater in those localities. In order to estimate the levels of groundwater contamination in these localities, a project on the monitoring of ground water quality around solid waste disposal sites in Delhi has been taken up. Groundwater samples in around the sites will be collected and analyzed for various physicochemical parameters including heavy metals, pesticides, and bacteriological parameters. The samplings were undertaken for four seasons such as summer, monsoon, post monsoon and winter.

7.26 ANALYTICAL QUALITY CONTROL (AQC/WATER) FOR THE LABORATORIES OF POLLUTION CONTROL BOARDS/COMMITTEES AND EPA RECOGNISED LABORATORIES

Analytical Quality Control (AQC) is one of the tools for generating good and accurate data. Environmental measurements and subsequent data generation should be high quality, in order to take good and correct decision for environmental management. Analytical Quality Control (AQC) is one of the main components of Quality Assurance system, wherein the quality of analytical data being generated in any laboratory is controlled through minimizing or controlling errors to achieve target accuracy. The AQC exercise is a routine activity of Central Pollution Control Board for improving the analytical capability of the concerned laboratories besides enhancing integrity of the data being reported upon.

Analytical Quality Control (AQC) is one of the main tools by which the performance of a laboratory can be assessed in terms of accuracy and reliability of analytical data generated by the laboratory. The Central Pollution Control Board (CPCB) is monitoring 507 water quality monitoring stations under GEMS, MINARS, GAP and YAP Programmes comprising rivers, lakes, wells, and ground waters spread over 23 states and five Union Territories through various State Pollution Control Boards (SPCB). In order to obtain reliable and accurate analytical data, CPCB has started regular and organized Analytical Quality Control (AQC) exercise for about 110 laboratories of SPCB/PCC, Environment (Protection) Act recognized laboratories Under this project, 9th round of AQC exercises covering 21 physico-chemical parameters were carried out during 2001.

The overall performance of the laboratories was assessed for various parameters as listed below. Ammonical Nitrogen, Chloride, Chromium, Calcium, Boron, Total Hardness, Potassium, Total Dissolved solids, Conductivity, Chemical Oxygen Demand, Sodium, Magnesium, Fluoride, Sulphate, Total Kjeldahl Nitrogen, Nitrate-N, Biochemical Oxygen Demand, Fixed Dissolved solids, Total Suspended Solids, Phosphate-P, pH.

7.27 DEVELOPMENT OF CERTIFIED REFERENCE MATERIAL (CRM) OF GAS MIXTURES

Central Pollution Control Board has undertaken a study to develop standard gas mixtures. The study is being carried out under a project sponsored by Department of Science and Technology (DST). Standard gas mixtures are an accurate and cost effective method for calibrating air monitoring instruments. They are stable and provide a repeatable reference concentration that can be used for regular calibrations. Each air quality standard contains one or more components mixed with nitrogen or air. At present there is no agency in the country, which has the capability and authorization to certify gas standards. On successful completion of the study, CPCB will qualify as a center for traceability of all gas measurements. Traceability of gases is necessary if the standards which are directly traceable to national primary gases, not only do the quality of measurement increases but at the same time measurements performed in different laboratories can be compared.

The Static Injection system and the Dynamic dilution system installed in the laboratory were employed for developing the gas mixtures. The above systems have been thoroughly tested and had been used for conducting five rounds of inter-laboratory comparisons of gas measurements, in addition to calibration of air monitoring analysers. Results from the inter-laboratory comparisons have shown that the standards developed by CPCB are comparable and reliable. Trial attempts have also been conducted to refill gas cylinders with low concentration (ppb levels) of gas mixtures. These low concentration gases in gas cylinders can be directly used for calibrating air monitoring analysers installed in the field stations thus preventing the cumbersome process of transporting analysers to the central lab for calibration. In the last phase of the project it is envisaged to compare gas standards produced in CPCB with standards procured from internationally reputed agencies such as NIST, USA to ensure that the gas standards produced are comparable and traceable to international standards.

7.28 FOLLOW-UP ON NABL LABORATORY ACCREDITATION OF CENTRAL POLLUTION CONTROL BOARD’S LABORATORY

The follow-up continued further for NABL Accreditation Central Pollution Control Board’s laboratories by National Accreditation Board for testing and calibration Laboratories, Department of Science & Technology, New Delhi. As a part of implementation of quality assurance system at Central Pollution Control Board laboratories. The following activities have been undertaken during the year:

Ø Quality plans for analysis of various parameters has been drafted and finalized.

Ø Contribution and periodical review of activities in laboratory Incharges Meetings organized from time to time viz. 7th Meeting: 23.5.2002; 8th Meeting: 3.9.2002; 9th Meeting: 13.11.2002; 10th Meeting: 14.1.2003; 11th Meeting: 4.3.2003.

Ø Internal auditing of laboratory and verification of facts during auditing during October 3-4, 2002 and closing meeting on 7th October, 2002.

Ø Internal auditing and verification of facts of implementation of points of auditing.

Ø Second Management Review Meeting related with NABL accreditation system was held on 9th January, 2003 at CPCB Conference Room, 2nd Floor.

Ø Presentation of Sh. S. K. Karmakar, consultant on `Introduction of ISO/IEC 17025’ on 23rd May, 2002.

Ø NABL Accreditation Team comprises Sh. V. Sesharaman, Lead Assessor; Sh. S. K. Gaind, Dr. S. K. Raza, Dr. R. S. Saini and Dr. B. K. Rana visited CPCB Laboratories during 25th – 26th March, 2003 for Quality Assessment for Accreditation of CPCB Laboratories.