ENVIRONMENTAL RESEARCH

Impact of Idols immersion in river Yamuna in Delhi

The impact of immersion of worship idols in Yamuna River after Dushehra festival has been studied at Delhi stretch from upstream Wazirabad to downstream Okhla barrage. It was estimated that as many as 1600 idols were immersed in Delhi stretch of River Yamuna. The impact on water quality of river with respect to levels of Conductivity, Total and Dissolved solids, Bio-chemical oxygen demand have been observed. River bed sludge analysis reflects elevated levels of iron, arsenic and mercury. Based on the study the following measures are suggested to reduce the pollution load from idols immersion activities.

- The offerings like flowers & leaves may be collected in separate containers or in pits for composting.

- After immersion, the recyclable articles like jari, clothes, plastics aluminium foil, wood and bamboo may be taken out from the water bodies. The civic authorities may engage agencies/persons for doing the job.

- Areas may earmarked for immersion & such other activities to prevent indiscriminate disposal and to help retrieval of recoverable materials.

- Environment friendly practices such as use of bio-degradable dyes and paints may be encouraged.

Spore Testing Methodology for Efficiency Testing of Autoclaves used for Bio-Medical Waste Treatment

Bio-medical waste treatment and its safe disposal has become a matter of serious concern in recent years. The Bio-medical Waste (Management & Handling) Rules, 1998 notified by Govt. of India has stipulated rules for proper collection, storage, transportation, treatment and disposal of bio-medical waste. For treatment of bio-medical waste, the nursing homes and hospitals have to install the treatment facilities for bio-medical waste like incinerators, autoclaves etc. and it is necessary that these treatment facilities should operate at designed efficiency level.

For assessment of efficiency of autoclaves, spore testing methodology has been undertaken by using the spores of Bacillus Stereothermophilus, which act as biological indicator. The assessment of efficiency of autoclaves installed at various hospitals of NCT Delhi and Hydroclave installed at Bhaunti, Kanpur was undertaken regularly. The observations and findings indicate that the bio-medical waste treatment by autoclaves/Hydroclave was satisfactory with respect to waste sterilization undertaken at various hospitals monitored.

Determination of Effluent Toxicity from Pulp and Paper Industries

For the development of toxicity based Minimal National Standards in Agro based or mixed type of pulp & paper industries, the collaborative project study had been carried out in collaboration with four prominent laboratories viz. National Institute of Occupational Health, Ahmedabad; Gujarat Pollution Control Board, Gandhi Nagar; and CPCB Zonal Laboratories at Kanpur and Delhi.

The analytical results indicate that the toxicity factor (TF) in the untreated effluent ranged between 1 to 16 whereas in treated effluent, its value ranged between 1 to 4. The range of percent toxicity reduction after treatment varied from 0 to 100%. In few cases, increase in the level of toxicity after treatment was also observed.

On the basis of studies, the toxicity standard for pulp and paper industries under Minimal National Standards (MINAS) has been recommended as TF 2. The standard indicates that the treated effluent should not cause any fish mortality, if exposed in the effluents diluted two times with specified dilution water, for a period of 48 hours.

Development of Trihalomethanes (THM's) Analysis Facilities for Environmental Samples (Drinking Water)

The halomethanes include all one carbon compounds with substituted chlorine or bromine. The sources of these compounds are industrial discharges and the synthesis during disinfection with chlorine. Trihalomethanes (THM's) occur in drinking water principally as a product of reaction of chlorine with naturally occurring material and bromide that may also be present. With respect to drinking water contamination, four members of THM's viz. chloroform, dichlorobromomethane, dibromochloromethane and bromoform are important. World Health Organisation (WHO, 1993) has already enacted the health related guidelines values in drinking water.

In order to monitor the presence of these compounds in drinking water, the infrastructure facilities are being developed at CPCB Laboratories.

Geo-accumulation and Bio-accumulation of Heavy Metals and Pesticides

With increasing paucity of fresh water untreated/partially treated sewage water is increasingly utilized for irrigation of soil and growing of crops. The sewage wastewater generation from urban areas has been constantly increasing, while the wastewater treatment capacity is quite less than the total wastewater generation. The treated/untreated wastewater is increasingly utilized for irrigation of crops, vegetation etc. To study the impact of wastewater on geo-accumulation and bio-accumulation on irrigated soil and crop vegetation in Delhi, a project has been undertaken.

The survey has been conducted at Najafgarh drain basin and dry cultivated areas in river bed of Yamuna after confluence of various drains, where sewage water is being used for irrigation of soil and growing crops vegetation. Water, soil, plants and vegetables such as Brinjal, Spinach, Bitter gourd, Lady's finger etc. have been collected and analyzed for trace metals and pesticides during consecutive random sampling rounds. From the analytical data, it has been derived that sewage irrigated soil and vegetables may contain elevated level of selective metallic content, which may be the cause of one or the other disorder.

Detection of Pesticides and Metals in Fish in West Bengal

With the increasing influx of industrial effluents in rivers, ponds and sea, there is possibility of contamination of metals in fishes. Keeping this in view, a study was carried out to ascertain the level of metal content in edible fishes, consumed by human, from different sources.

Fishes from two locations (Digha and Diamond harbour fish landing stations) from the coast of West Bengal were collected for the analysis of heavy metals. Results indicate that the concentrations of all metals analysed were within the prescribed limits for human consumption.

Assimilative capacity studies of different rivers

Wastewater of industrial and domestic origin is ultimately discharged into the rivers. The natural assimilation capacity can take care of these pollutants to some extent, though discharge of excess pollutants may upset such system. Capacity of assimilation of pollutants generally varies from river to river. If capacity of assimilation can be ascertained the fate of the pollutants can be predicted.

A study has been undertaken to assess the fate of chemicals added to the limited quantity (20 lits) of river water with aeration. Different type of carbohydrates, metal, urea etc were added to the water and samples were collected at 2 hours interval for analysis of pH, BOD, COD, TKN, NO3, ammonia, total coliform and metals.

The results obtained using river water collected from Hugli revealed that decreasing trend was observed for BOD, COD and alkalinity whereas increasing trend was observed for pH, nitrate, and total coliform along with lowering of biodegradability. The metals like iron, zinc, manganese were removed sharply due to co-precipitation.

Pollution potential of leachates from SW & BMW dump sites at Dhapa - Bantala, West Bengal

Recycling of solid waste is of two types, namely (i) Vegetable cultivation and (ii) picking from the disposal ground. Nutrient recycling by way of growing vegetables on such solid waste dump provides a very effective route for solid waste management. However, such dumping may lead to soil and groundwater pollution due to, among others, its high content of toxic compound.
To study the 'Pollution potential of leachates from solid waste' an active dumping site is chosen at Dhapa, where newly developed Bio-medical waste treatment facility has been build up and the other site which is chosen is the old dumping site marked as Bantala area, a site selected for promotion of Hotels and Resort (P.C Chandra Green Project) situated opposite to the Science City. Lysimeters of 10 ft. have been installed at both the sites.

In the present study quality of leachates from 10-ft depth of active dump has been examined by way of assessing the relevant physical, chemical and even biological properties of the same. For this purpose leachates are being collected at regular interval from the month of August.

The results of analysis reveals that microbial contamination is very high as well as the presence of toxic metals like manganese, iron, lead, zinc, chromium, Sodium and potassium concentrations are also found above the recommended standard for drinking water and irrigation water quality criteria.

Pollution Potential of Leachates from Solid Waste Dump

During the study, quality of leachates from different depths of active dump/soil is examined by way of assessing the relevant physical, chemical and biological properties. For this purpose, leachates from designated depths are collected at regular intervals with the help of soil sampler (or lysimeter). Transport of solution down a profile plays a significant role in determining the accumulation at any particular depth and often bears relationship to the potential for contamination of groundwater reservoir. The ability to predict the mobility of dissolved solutes in the soil solution (i.e. leachate) is of considerable value in managing and disposal of solid waste. Indeed salt concentration gradient may greatly affect water movement in soils. The study of these processes is relevant with regard to modes of leaching solute accumulation nutrient movement, evaporation, as well as ground water pollution. The present study has been concentrated with the parameter such as reflection coefficient (d) mechanical filtration capacity (Lp), solute permeability.

In addition, column studies may also be undertaken in the laboratory under conditions simulating those existing in the field/dump. Attempts may be made to relate the findings to the Darcy's hydraulic conductivity, solute accumulation and relative hold-up of solutes by the given perineating media, as represented by the breakthrough curves. This could be of interest for a better understanding of the deposition as well as concentration of the dissolved solutes down the soil profile.

Coastal Aquaculture in India

There are about 1.2 million hectares of brackish water area of which about 0.14 million hectares is used for shrimp farming. This rapid expansion is likely to lead to a number of social and environmental problems. A study is being carried out to assess the pollution potential of the coastal aquaculture. Some of the observations made during the study are unlike other industrial processes, as it is not a continuous process and it runs twice annually. Therefore, the discharge of effluent is one time during the season in which huge quantity of wastewater is discharged in a short span of time in specific area.