STUDY AREA
3.17 DATA COLLECTION
To assess the effect of water and wastewater quality on various environmental aspects such as aquatic lives, human health etc. various water and wastewater quality parameters were monitored. The parameters monitored for this purpose were pH, color, turbidity, alkalinity, Biochemical Oxygen Demand (BODs), Chemical Oxygen Demand (COD), Faecal coliform and Nitrate.
The physical, chemical and biological qualities of the water and wastewater were assessed through laboratory test. The experimental procedure of each parameter is described in a nutshell in this section.
(i) pH: pH, determined by ASTM Dl293-84 (ASTM, 1988) was carried out by electrometric measurement using the glass electrode as the sensor. pH was determined calorimetrically by choosing indicators with colors that are highly pH dependent in HACH DR-EL/4 Photo spectrometer(HACH, 1984).
(ii) Color: Color caused by colloidal form of impurities is called true color and that caused by suspended matter is called apparent color. Color was determined by HACH DR-EL/4 apparatus using diluted sample (APHA, A WW A, WPCF, 1985) (iii) Turbidity: Turbidity was measured by the deflection of light caused by variety of
suspended matter, depending upon the degree of turbulence. Turbidity was measured by Nephelometric method with turbidimeter using highly diluted sample.
(iv) Alkalinity: The alkalinity of water is due principally to salts of weak acids and strong bases. Alkalinity is measured volumetrically by titration with N/50(i.e.
0.02N) H2S04 and is reported in terms of equivalent CaCOJ.
(v) Biochemical Oxygen Demand (BOD): BOD test was performed according to the recommended winkler procedure described in Methods 507 (APHA, A WW A, WPCF,1985).
(vi) Chemical Oxygen Demand (COD): In the determination of COD, equal volumes (lOml) of diluted sulphuric acid and potassium permanganate are added to 100mi of sample and heated in a water bath for 30 minutes. 10mi of standard ammonia oxalate is added to the boiled sample. The standard potassium permanganate is then added to the mixture until first permanent pink color is obtained from the additional volume of standard potassium permanganate added to the sample. '
(vii) Faecal Coliform: It is important to note that the sensitivity of this test depends on heat shock. Which inhibits non-faecal coliform organism. Therefore, the culture was placed into MF-Millipore incubators at 45 degree centigrade temperature.
The filter was examined after 24 hours by a strong magnifier and in presence of light. Non-faecal coliform usually produces a gray to cream color.
(viii) Nitrate: Determined by HACH Program 2520 N, Nitrate MR. The reagent used was Nitra Ver 5 Nitrate Reagent powder pillow.
3.17.5 Test Result and Analysis:
The tests carried out in DND area in five locations during September 200 I are presented in the Table-3.9. Some of the results were found within the acceptable range but some were not. It is observed that in all cases the Color, Alkalinity, Nitrate, COD and BODs values increased in Sitalakhya downstream than its up stream because of the industrial pollution load from industries like Karim Jute mill, SCAN cement etc lying down side of the river. DND canal would be used to supply water from the river Sitalakhya. The BOD value of DND canal was found higher than the acceptable limit of 3mg/1. This is because the water was stagnant during test period and the Saidabad water treatment plant was non-functioning at that period. Considering BOD value the water of the river Lakhya may be used for drinking purpose after conventional treatment. The BOD value for the stagnant water was found high because of the presence of water plant in the pond, which decomposes. For all the locations COD, pH, Alkalinity, Color, turbidity and Nitrate value found are within the acceptable limit. From the test it is observed that the quality of ground water in Jatrabari area is acceptable.
Table: 3.9 Comparative statement of various tests around DND Area Test Period September 2001
Locations pH Color Alkalinity Nitrate Turbidity FC COD BODs
as CaCo]
(TCU) (mg/I) (mg/I) (NTU) (Nr) (mg/I) (mg/I)
Sitalakhya 6.7 65 5.8 0.3 17
-
2.61.6
-up
Sitalakhya- 6.7 170 7 0.4 67
-
3.32
Down
Stagnant 7.4 71 14 0.2 46 600 9.6
6.6
Water
DND Canal 7.3 74 14 0.2 27 2000 7.3 4.7
Jatrabari 7.0 8 16.5 0.2 0.57 Nil 0.5
0.3
WASA
4.1 Introduction:
CHAPTER-4
Probable Discharge Point From N. Gonj to downstream Laklya, Tejgaon to Balu Turag khal to up stream Balu.
Ghorasal to Lakhya
N. Gonj to down stream Lakhya, Tejgaon to Balu, Tongi to up-steam Balu Tejgaon to Balu Tongi to Balu Type of Pollutants
Oil, grease, chlorinated Hydrocarbons acids, alkalis, HZs. CN, Cr, Cd, Ni, Cu, Zn, Ag
Acid mists, vapourts Metal and lime sludges.
Cr, Pb, Cu, Cd, organic, solvents, Cyanides Organic solvents, Packing materials (rejected paint cans)
Alkali, CI. Dyes, organic matter, detergents, N,P,SS
SMP, yam, cloth, packing Materials, ink waste
Organic matter, 55, NH], color, Zn, Hg, Sox, particulate matters, Wastewater sludge, ash, bark wood waste, paper etc.
H2S04, H)P04, HF, fluorides, phosphates, NH, NH4- , salts, Amins, CH3-0H, HZs, SPM, fluorides, CH3, HZ, S, Ash, gypsum
Wastewater Gaseous emission Solid waste Wastewater Gaseous emission Solid waste Type of Emission Wastewater Gaseous emission Solid waste Wastewater Gaseous emission
Solid waste Wastewater Gaseous emission Solid waste Industries
Electroplating Industries
Paint Industries
4.2.1 Surface Water Quality:
Fertilizer Industries
ENVIRONMENTAL IMPACT ASSESSMENT
Paper and Pulp Industry Textile Industries (Dying &Printing)
Table 4.1: Examples of some Polluting Industries around Balu and Lakhya River Surface run-off include the pollution load run-off due to all human and other related concerns such as domestic, industrial, agricultural and other related activities. The river Sitalakhya is mainly used for navigation purposes. Regarding pollution load concern, Sitalakhya River receives discharges from all the industries situated up and down stream (Table 4.1) which include Textile, Jute Mills, Soap Industries, Pulp and Paper Mills's etc.
A few of them have some effective treatment plant. Besides the industrial pollution, the domestic effluent is also discharged into the Lakhya. Engine boat and shipping activities are also added considerable source of pollution to the river in terms of oil and grease.