Impact of Onsite Sanitation System on Groundwater in Different Geological Settings of Peri Urban Areas

Available online at www.sciencedirect.com

ScienceDirect Aquatic Procedia 4 (2015) 1162 – 1172

INTERNATIONAL CONFERENCE ON WATER RESOURCES, COASTAL AND OCEAN ENGINEERING (ICWRCOE 2015)

Impact of onsite sanitation system on Groundwater in different Geological settings of Peri Urban areas. Shivendra. B. Ta*, Ramaraju. H. Kb a b

Dayananda Sagar College of Engineering, Kumarswamy Layout, Bangalore-560078, India Dayananda Sagar College of Engineering, Kumarswamy Layout, Bangalore-560078, India

Abstract Pit Latrines and Septic tanks are common modes of onsite sanitation commonly used in India. These modes of onsite sanitation are becoming source of Groundwater contamination. The chemical contaminants and pathogenic bacteria released from these onsite sanitation systems are in filtered into the surrounding groundwater sources through soil media and causing the threat. This threat is more severe in dense habitation where both onsite sanitation and drinking water resources are spaced very close. In the present study Field investigations are carried out in peri urban areas having different geological settings in Bangalore Rural district and Ramanagara district. Water and soil samples are collected during all seasons of a year near onsite sanitation system and analyzed for critical pollution parameters. The analysis of results reveals that concentrations of critical parameters exceeding the permissible limits of drinking water quality. © 2015 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license

© 2015 The Authors. Published by Elsevier B.V. (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of organizing committee of ICWRCOE Peer-review under responsibility of organizing committee of ICWRCOE 2015 2015. Keywords: Onsite Sanitation System; Groundwater Contamination; Nitrate; E-coli

1. Introduction Due to the requirement of enormous investment in capital costs, high operation and maintenance cost, severe financial constraints and requirement of considerable quantity of water, sewerage is not the answer to solve the

* Corresponding author. Tel.: +0-973-181-2013; E-mail address: [email protected]

2214-241X © 2015 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of organizing committee of ICWRCOE 2015 doi:10.1016/j.aqpro.2015.02.148

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problem of human waste management in India. The majority of people living in the rural areas and on the urban fringes in developing countries still lack satisfactory sanitation. Septic tank and pit latrine modes of on-site sanitation systems are commonly used in India. Septic tank has problems like periodic cleaning and disposal of sludge. In urban areas where household and communal toilets are more prevalent, 2.1 billion people use toilets connected to septic tanks that are not safely emptied or use other systems that discharges raw sewage into open drains or surface water bodies. (WHO2013).Effluent disposal from septic tank is a potential source of foul smell, mosquito breeding and health hazards. Leachate from onsite sanitation system is the one the source of ground water pollution. (ARGOSS 2001) The chemical contaminants and pathogenic bacteria released from these onsite sanitation systems are in filtered into the surrounding groundwater sources through soil and causing the threat. This threat is more severe in dense habitation where both onsite sanitation and ground water resources are spaced very close. There is shortage of drinking water in almost all peri urban areas of the country; hence water has to be conserved. Contamination of drinking water by pathogens and nitrate are two major public health issues commonly related to onsite systems. (Lewis.et.al 1980) Lot of research work is carried out by various authors on the assessment of impact of on-site sanitation system on groundwater contamination(Kligler 1921, Caldwell and Parr 1937; Caldwell 1938b; Dyer 1941 , Viraraghavan 1978 , Brown et al. 1979 Lewis et al. 1980 Nichols et al. 1983, Padmasiri et al. 1992, Chidavaenzi et al. 2000; H.K. Ramaraju2009, Lawrence et al. 2001; Chidavaenzi etal.2002; Dzwairo et al. 2006 Pujari et al. 2007; Lu et al. 2008; Banerjee 2011, Sudhakar .M Rao, et.al 2013 ). In their studies they used installed observation wells or existing wells on the downstream side of on-site sanitation system for collection of water sample or soil samples or both during wet and dry seasons. The extent of groundwater pollution, depends on hydro geological and soil condition of surrounding Environment, depth to water table and distance between groundwater source and onsite sanitation system. In addition to above along with onsite sanitation system, the ground water pollution increased by livestock and stored manure, solid waste landfills and leakage from wastewater pits.(Banks et,al 2002). The highest nitrate concentrations in groundwater were associated with the highest population and pit latrines densities of the settlement.(Zingoni et.al.2005).Chloride, nitrate, and fecal coli forms are the indicator parameters used to assess impact of onsite sanitation systems by most of researchers((Lewis et al. 1980; Lawrence et al. 2001).The studies by (Chidavaenzi et al. 2000; Mafa 2003; Vinger et al. 2012) found that higher concentration of nitrate above the drinking water standards. near downstream side of the onsite sanitation system, on the other hand studies by (Baars 1957; Vinger et al. 2012) found nitrate concentration is below the drinking water standards. Dzwairo et al. (2006) in their studies on assessment of impact of pit latrines on groundwater in Kamangira village in Zimbabwe found that the microbiological impact up to 25 m from onsite sanitation system. Studies on impact of septic tank system on groundwater quality carried out in India, and China by Pujari et al.( 2007) and Lu et al. (2008).found increased concentration of nitrate and bacteria in groundwater near onsite sanitation system. In study carried on microbial movement near onsite sanitation systems by Banerjee2011 in West Bengal in India found that increased concentration of total and fecal coli form during monsoon period in saturated condition of sandy soils and less in clay soils . In his studies he observed safe distance between on-site sanitation units and groundwater supply sources is 10 meters. The National Environmental Engineering Research Institute (NEERI), Nagpur conducted study on impact of onsite sanitation on ground water in ten cities of India. The study concludes that geological setting also plays in groundwater contamination in addition to other parameters. The groundwater pollution due to on-site sanitation system relates primarily to unconfined and, to a lesser degree, to semi-confined aquifers. If groundwater supplies are drawn from deep and confined aquifers, on-site sanitation does not pose a significant hazard. Hence the hydro geological characteristics plays a role in groundwater contamination due to onsite sanitation systems.(NEERI 2005) .In their studies they found that study area with shallow water table and fracture rock aquifers were contaminated more compared to alluvial formations. Sudhakar .M. Rao, et.al (2013) in their studies on Impact of pit-toilet leach ate on groundwater chemistry and role of vadose zone in removal of nitrate and E-coli pollutants in Mulbagal town, India found that the nitrate concentration of 30-140 mg/l in surrounding bore wells near onsite sanitation system. The nature of the geological strata and thickness of the unsaturated zone determine risk of pollution. Groundwater flow in unsaturated soils normally does not exceed 0.3 meter/day (Lawrence et al. 2001). An important exception may occur in fissured rocks and coarse gravels. Flow rates in excess of 5 meter/day may occur in fissured rocks and coarse gravel (Franceys et al. 1992) and the potential for

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groundwater contamination under these conditions is extremely high. The rock type, and especially the grade of consolidation and presence of fractures, is key factors in assessing vulnerability of aquifer to pollution. The extent of contamination of Groundwater wells is poorly recognized in many developing countries because of lack of monitoring. Hence, monitoring of groundwater water quality is essential. A comprehensive study and assessment of contamination of ground water sources and to suggest corrective & remedial measures for its mitigation is the present need of the society. With this background, in the present study Field investigations are carried out in peri urban areas having different geological settings in Bangalore Rural district and Ramanagara district. Water and soil samples are collected in all seasons of the year near onsite sanitation system and analyzed for critical pollution parameters and to know the status of nearby ground water. 2. Objectives of the Study The objective is to assess threat of contamination to Groundwater and practical means of evaluating future vulnerability based on Hydro-Geological features of the area, To predict the impact of low cost on site sanitation system on subsurface water and soil environment. To establish safe distance between on-site sanitation units and Groundwater supply sources, to suggest remedial measures for prevention of contamination of Groundwater. 3. Study Areas 3.1. Doddaballapura Doddaballapura is a peri urban town 40 Km from Bangalore City. Doddaballapura (Table.1) is located at latitude 77° 32′ 34.8″ E and longitude. 13° 17′ 31.2″N. The area is characterized by undulating topography with Dendritic to subdendritic drainage system. The elevation of the area ranges from 917 to 1175 above Mean sea level (MSL). The city has a population of 85,000 as per the census of 2011. The geographical area is 7.2 square kilometres. The surface geology is Tonalitic Gneisses and Gneisses. The soil is Sandy loamy, Clay and Loamy sandy. The average Annual rainfall is 768mm. Doddaballapura is 100% depended on ground water, with municipal and private water supply. Water is drawn from 400-600 feet and is declining. The major source of potable water is tankers (50%) and Municipal water (47%). The city has very limited sewer connection and is under construction Most of houses in the areas have septic tanks. 25% of people has access to private toilets, 76% own toilets and 09% shared toilets. 15% of population does not access to private toilet.7% community toilet and 8% open toilet. The main reason for not having toilet is financial constraints (61%) and space (65%) (ASHWA). Water table is very deep in the city and tube wells are the common water sources. The depth of the well varies from 400-800 ft and distance of sanitation pit from bore well varies from 10 -150feet. People are dependent on the public bore wells installed by the Municipal Corporation there are public tube wells at many places in the locality. The public tube wells are also close to the open drains, which carry the sullage as well as effluent from the toilets. The sampling locations were decided on the basis of visits to different localities. Preliminary survey is carried out in selected layout of study areas by visiting the houses. Details regarding sources of water supply, sanitation and health related disease is collected by questionnaire. After preliminary survey, Sampling points are fixed based on distance between source of water and sanitation system. 09 (Nine) Bore well water sampling locations are selected in the T-cross, D-Cross, Sommeswara Extension and R.L. Jalappa Engineering Extension. All the houses in the localities are not having proper collection of waste water and unsewered with septic tanks and disposal of sullage water in open drain is commonly observed. 3.2. Kanakapura Kanakapura is a town and the headquarters of Kanakapura Taluk in the Ramanagara District in the state of Karnataka, India. Kanakapura (Table.1) is situated 55 km south to Bangalore on the banks of the river Arkavathy and this town is famous for the production of silk and Granite. Kanakapura is located at12.55°N 77.42° E. It has an average elevation of 638 meters. The geographical area is 7.2 Square kilometres. The surface geology is Granodiorite and granite. The soil is Sandy Clay Loamy. The average annual rainfall is 750mm. As of 2011 India census, Kanakapura had a population of 70,150. Kanakapura is depended on ground water, and municipal water supply. Water is drawn from 150-300 feet and is declining. The distance of sanitation pit from bore well varies from

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10 -150feet. No Sewerage facilities is existing in town and septic tanks are common mode of sanitation used in the residential areas and waste water is diverted through major storm water drains to Arkavathy river and tank near melkote. The sampling locations were decided on the basis of visits to different localities. Preliminary survey is carried out in selected layout of study areas by visiting the houses. Details regarding sources of water supply, sanitation and health related diseases are collected via questionnaire. Bore well water sampling locations are selected in Municipal area and Housing board area, Melkote and Rice mill area. All the houses in the localities are not having proper collection of waste water and unsewered with septic tanks and disposal of sullage water in open drain is commonly observed.

Fig.1. Location map of Study Area Table 1. Study area Details. Study site location

Doda ballapura (D and T cross and Someswara extension) Kanakapura (Municipal area, Melekote Muncipal court area)

Densi ty of popul ation Sq/k m

5642

9743

Mean annual rainfal l (mm)

Surface Geology

Soil type

768

Tonalitic Gneisses And Gneisses

Sandy loamy Clay Loamy sandy

750

Granodiori te and granite

Sandy clay loam

Sampl ing points monit ored

09

10

Nos of users in the families Max Min

10

80

6

04

Age of the tank Max

11

25

Type of construct ion

Min

Distance of tank From drinking water source (m) Max

Min

Fro m agric ultur al field (m)

02

Size stone masonry /rubble dry masonry

50

4

1000

05

Size stone masonry /rubble dry masonry

50

3

45

4. Material and Methodology Reconnaissance survey is carried out in selected layout of study areas by visiting the houses. Details regarding sources of water supply, sanitation and health related diseases are collected by questionnaire. After preliminary survey, Sampling points are fixed based on distance between source of water and sanitation system. 8-10 bore well

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water sampling locations are selected in each Taluk and continuously water samples are collected monthly from April 2013 to April 2014. Water samples are collected as per standard methods (APHA) in 2Litre plastic cans for physico-chemical analysis and 300 ml water sample in sterilized bottle for bacteriological study. The parameters analyzed are tabulated in Table 2 and 3. The parameters are also compared with the Bureau Indian standards .Soil samples were collected in all four direction of the pit at a distance of 1, 3,5m horizontally from the edge of septic pit and vertically at depth of 0.5, 1.01 and 1.5m.The soil samples were collected in polythene bags and were carried to laboratory for analysis of Macro and Micro nutrients and for horizontal and vertical direction movement of pathogens. Soil samples will be analyzed for physical properties( sieve analysis, permeability, bulk density, Specific gravity, Moisture content, Dry density, Void ratio, Porosity, Degree of saturation), in Geotechnical laboratory, Chemical (organic content, Electrical Conductivity, pH, available Phosphorus, available Potassium, Micro nutrients-Zn, Cu, Mn, Fe, Ca), and Biological parameters(Total coli form, E-coli) . 5. Results and Discussions 5.1. Water Sample Analysis Nine (09 nos.) groundwater samples were collected from the study areas of Doddaballapura during the study (depicted in Maps) period from April 2013 to April 2014.and analyzed for physico-chemical, and bacteriological parameters. Table.2. presents the values of Total dissolved solids, Chloride, Nitrate, Total coli forms and E-coli for all the three seasons. The values of Total Dissolved solids varying from 628-1371 mg/L during pre monsoon season, 609-1278 mg/L for Monsoon and 641-1080 mg/L. Post Monsoon as shown in. Fig 1.1 and Table2 .The values show not much variation in the three seasons. In study area 75% of samples are having maximum values of Total dissolved solids and are exceeding WHO Guideline of 1000mg/l. The bore water is not good for drinking purpose and is unpalatable. Except D3 and D6 all sampling stations Total dissolved solids are beyond drinking water standards. The high values of TDS can be attributed to the local geo-chemical characteristics. The values of chloride varying from 126-452 mg/L during pre monsoon season,129-454 mg/L for Monsoon and 213-610 mg/L Post Monsoon as shown in Fig 1.2 and Table1. In study area 90% (Except D3 station) of samples are having maximum values of chloride and are exceeding permissible limit of 250 mg/l. The values in pre monsoon, monsoon and post monsoon seasons show much variation. The values of chloride are maximum during post monsoon seasons. The Nitrate values are in the range of 4.1 to 28.3 mg/L during pre monsoon season, 2.1 to 17.46 mg/L for Monsoon and 9.45 to 27 mg/L Post Monsoon as shown in Fig .1.3 and Table1. In general, all the samples are within the desirable limit of 45 mg/L. Sample collected near D-cross shows less values of Nitrate compared to Sommeswara Extension and R.L. Jalapa Engineering College Extension. Nitrate concentration is more in winter than in summer and monsoon. The high nitrate values are noticed in post-monsoon the decrease in summer season can be attributed to the lowering of the groundwater table wherein anaerobic condition is created and nitrate is partially converted to nitrogen (Lawrence et al. 2001). The Total coli form count varies from 2/100 ml during pre monsoon season, 3 to 4 /100 ml Monsoon and 2 to 3 /100 ml mg/L Post Monsoon as shown in Fig .1.4 and Table2. The presence of Total coli form is observed in the entire sample during all seasons. The count is more in monsoon compared to other seasons. Apart from on-site sanitation systems, there are sources like open drains in the vicinity of the sampling locations, which carry the domestic wastewater from the houses. They may also contribute to the contamination the overall observation in Doddaballapura is that Total coli forms are present in bore water samples located at a considerable distance from the septic tank. Hence presence of Total coli forms in those samples may be due to infiltration of Leachate from the septic tank .The infiltration and recharge in the monsoon can lead to faster movement of the pathogens in the vadose zone, and presence of fractures in the rock, may lead to reach the water table at a faster rate in monsoon as compared to summer. This can be responsible for increase in the survival rate of pathogens and thereby increasing the Total coli form concentration in monsoon.(Pujari.P.R.et.al 2013). The increase in water table leads to aerobic conditions and thereby increasing the survival rate of the coli forms. The presence of Escherichia-coli is not observed in any of the sample during all seasons. Ten (10 nos.) groundwater samples were collected from the study areas of Kanakapura during the study period from April 2013 to April 2014 were analyzed for physico-chemical, and bacteriological parameters. Table 3 presents

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the range of Total dissolved solids, Chloride, Nitrate, Total coli forms and E-coli for all the three seasons. The values are compared with Indian standards. The values of Total Dissolved solids varying from 489-1473 mg/L during pre monsoon season ,480-1354 mg/L for Monsoon and 504-1404 mg/L Post Monsoon as shown in. Fig 2.1 and Table. 2. In study area 75% of samples are having maximum values of Total dissolved solids and are exceeding WHO Guideline of 1000mg/l. The bore water is not good for drinking purpose and is unpalatable. Except K3 and K4 all sampling stations have Total dissolved solids are beyond drinking water standards. The high values of TDS can be attributed to the local geo-chemical characteristics. The values of chloride varying from 142-450 mg/L during pre monsoon season, 79-430mg/L for Monsoon and 84-435 mg/L Post Monsoon as shown in Graph2.and Table2.2 In study area 50% (K5 to K10 stations ) of samples are having maximum values of chloride and are exceeding permissible limit of 250 mg/l. The value of chloride is highest during post monsoon seasons. The nitrate values are in the range of 10.2to 49.5mg/L during pre monsoon season, 3.56 to 21.56 mg/L for Monsoon and 6.65 to 22 mg/L Post Monsoon as shown in. Fig 2.3 and Table 3. In study area, all the samples are within the desirable limit of 45 mg/L except K4 station. Sample collected near Municipal and Melekote areas shows less values of Nitrate compared to housing board area and Rice mill area.The Total coli form count varies from 0 to 7/100 ml during pre monsoon season, 3 to 20 /100 ml Monsoon and 02 to 4 /100 ml mg/L Post Monsoon as shown in Graph2.4 and Table.3. The presence of Total coli form is observed the entire sample during all seasons the count is more in monsoon compared to other seasons. The presence of E-coli form is not observed in any of the sample during all seasons. Table 2. Concentration of Indicator Parameters of Borewell water sample from Doddaballapura, Bangalore Rural Dist. Parameters

Total Dissolved Solids(mg/l)

Chloride(mg/l)

Nitrates(mg/l)

Total coliforms M.P.N/100ml

Seasons D1

D2

D3

D4

D5

D6

D7

D8

D9

Premonsoon

1245

1371

628

957

1346

739

1024

NM*

NM*

Monsoon

908

1115

609

823

1278

707

699

906

876

Post Monsoon

940

1080

641

856

1137

716

1015

942

870

Premonsoon

286

335

126

302

452

259

289

NM

NM*

Monsoon

308

408

129

297

454

251

236

299

312

Post Monsoon

347

370

213

407

610

305

250

405

343

Premonsoon

25.4

28.3

27.4

24

4.65

4.1

11.8

NM

NM*

Monsoon

17.46

14.7

9.3

5.84

2.1

4.5

3.1

10.33

14.44

Post Monsoon

21.3

21.1

19.85

11.55

13.6

11

9.45

17.55

27

Premonsoon

2

2

2

2

2

2

2

2

NM*

Monsoon

3

3

3

4

3

3

4

4

3

Post Monsoon E-coli;

Stations

2

2

3

2

2

2

3

3

3

Premonsoon

AB

AB

AB

AB

AB

AB

AB

AB

AB

Monsoon

AB

AB

AB

AB

AB

AB

AB

AB

AB

Post Monsoon AB AB AB AB AB AB NM=Not Measured DI toD9 are sampling stations at Doddaballapura,

AB

AB

AB

5.2. Soil Sample Analysis Soil samples were collected in all four direction of the pit at a distance of 1, 3 and 5m horizontally from the edge of septic pit and vertically at depth of 0.5, 1and 1.5m.The soil samples were collected in polythene bags and were carried to laboratory for analysis of Macro and Micro nutrients and for horizontal and vertical direction movement of pathogens. The soil physical properties are tabulated in Table.4.The soil at Doddaballapura site were sandy soils. These sites have organic content varying from 0.18 to 0.68 %. The soils were alkaline with PH varying from 7.7 to 8.3. The Electrical Conductivity is in the range of 0.10-1.23 and organic content is low (Measures of Nitrogen). Phosphorus is the second key plant nutrient and is required by all living organisms. In the study area it is

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Table 3. Concentration of indicator parameters of Bore well water samples from Kanakapura, Ramanagara Dist. Parameters

Seasons

Total Dissolved Solids(mg/l);

Chloride(mg/l);

Nitrates(mg/l);

Total coliforms M.P.N/100ml

E-coli;

K1

K2

K3

K4

K5

K6

K7

K8

K9

K10

Premonsoon

1062

1058

489

587

1281

1473

1124

1153

1160

1260

Monsoon

951

966

480

527

1222

1354

1033

1015

1032

1146

Post Monsoon

973

1137

504

535

1240

1404

1030

1028

1010

1228

Premonsoon

195

167

142

167

345

450

343

256

284

390

Monsoon

226

217

79

109

343

430

241

253

255

350

Post Monsoon

235

240

84

115

350

435

235

255

265

370

Premonsoon

29

21.06

18.6

49.5

16.9

17.8

24.5

29

25

10.2

Monsoon

21,56

14.16

5.7

12.67

14.9

11.37

9.63

14.43

15.03

3.56

Post Monsoon

22

18.1

13.7

14

16.4

16.1

21.4

23.6

13.7

6.65

Premonsoon

0

3

0

3

0

0

0

11

3

7

Monsoon

0

4

3

4

3

3

3

20

4

15

Post Monsoon

0

3

2

3

2

2

2

4

3

4

Premonsoon

AB

AB

AB

AB

AB

AB

AB

AB

AB

AB

Monsoon

AB

AB

AB

AB

AB

AB

AB

AB

AB

AB

AB AB AB AB AB KI toK12 are sampling stations at Kanakapura

AB

AB

AB

AB

AB

Post Monsoon

800

1500

600

1000 500

MONSOON

0

POSTMONSOON

400

Chloride

PREMONSOON

D1 D2 D3 D4 D5 D6 D7 D8 D9

Total Dissolved Solids

Stations

PREMONSOON

200

MONSOON

0 D1 D2 D3 D4 D5 D6 D7 D8 D9

POSTMONSOON

Stations Stations

30 25 20 15 10 5 0

Fig 1.2 Chloride variations among the the Sampling Station 5

PREMONSOON MONSOON POSTMONSOON D1 D2 D3 D4 D5 D6 D7 D8 D9

Total Coliform

Nitrate

Fig 1.1. Total Dissolved Solids variations among the Samping Station

4 3 2

PREMONSOON

1

MONSOON POSTMONSOON

0 D1 D2 D3 D4 D5 D6 D7 D8 D9 Stations

Stations Fig 1.3 Nitrate variations among the Sampling Stations

Fig 1.4 Total Coli form variations among the Sampling Stations

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Chloride

1500 1000 PREMONSOON

500 MONSOON

0

500 400 300 200 100 0

PREMONSOON MONSOON

POSTMONSOON

K1 K3 K5 K7 K9

Stations

Stations

MONSOON POSTMONSOON

Stations

30 20 10 0

PREMONSOON MONSOON K1 K3 K5 K7 K9

PREMONSOON

Total Coliform

Fig.2.2. Chloride variations among the Sampling Stations

K1 K3 K5 K7 K9

Nitrate

Fig.2.1 .Total Dissolved Solids variations among the Sampling Stations

60 40 20 0

POSTMONSOON

K1 K2 K3 K4 K5 K6 K7 K8 K9 K10

Total Dissolved Solids

2000

POSTMONSOON

Stations

Fig 2.3 Nitrate variations among the Sampling Stations

Fig.2.4. Total Coliform variations among the Sampling Stations

Table 4. Soil physical properties SL No

Location Community toilet with septic tank near D-cross Doddaballapura Septic tank near police station Municipal area Kanakapura

1 2

Specific gravity

Permeability m/day

Bulk density gm/cc

Dry density gm/cc

Void ratio

2.346

0.20

1.691

1.473

0.605

2.62

0.284

1.915

1.478

0.774

Table 5. Soil Analysis report for Physico-Chemical , Macro and Micro Nutrients (Doddaballapura) Sample point D11

D12

D21

D22

D31

Horizontal distance(M) 1.00

3.00

1.00

3.00

1.0

Depth (m) 0.50

7.9

1.23

OC (%) 0.21L

0.23D

0.66S

11.75S

19.98S

1.00

7.9

0.97

0.25L

8L

140H

0.69D

0.63S

16.38S

21.03S

1.50

7.8

0.83

0.32L

7L

112M

0.26D

0.74S

25.85S

68.98S

0.50

7.9

0.98

0.14L

8L

132H

0.85D

0.80S

5.295S

12.58S

1.00

7.9

0.71

0.18L

6L

102M

0.54S

0.54S

8.90S

12.58S

1.50

8.3

0.70

0.21L

7L

70M

0.55S

0.51S

14.83S

18.31S

0.50

7.9

0.92

0.28L

7L

120H

0.61D

0.82S

14.125

35.46S

1.00

7.9

0.89

0.29L

8L

85M

0.52D

0.71S

16.925

38.21S

1.50

7.8

0.73

0.31L

7L

60M

0.32D

0.48S

18.745

46.25S

0.50

8.0

0.65

0.25L

6L

72M

0.94D

1.31S

9,80S

31.24S

1.00

8.2

0.81

0.18L

7L

54M

0.33D

0.54S

8.89S

18.44S

1.50

7.9

0.96

0.21L

8L

38M

0.10D

0.36S

7.95S

8.59S

0.50

7.9

0.14

0.68L

9L

116M

1.40S

1.30S

12.59S

76.31S

1.00

7.7

0.10

0.40L

7L

90M

0.92S

1.10S

14.21S

79.40S

PH

(Dsm)

P205 Kg/ha 07L

K20 Kg/ha 320H

Zn

Cu

Mn

Fe

L=Low; M=Medium; S=Sufficient; E.C.=Electrical Conductivity; OC=Organic Content; P205 =Available Phosphorus; K20 = Available K

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B.T. Shivendra and H.K. Ramaraju / Aquatic Procedia 4 (2015) 1162 – 1172 Table 6. Bacteriological analysis of soil, Doddaballapura (Pre-Monsoon season) SL NO

Sample point

Horizontal distance (M) 1.00

Depth (M) 0.50 1.00

Total count CFU/100ml 0.6x109 0.2x109

Fecal count CFU/100ml 0.3x108 0.5x105

E-Coli CFU/100ml ABSENT 0.2x108

1

D11

1.50 0.50 1.00

1.6x109 0.1x106 ABSENT

0.7x108 0.2x107 ABSENT

1.2x109 ABSENT ABSENT

1.50 0.50

0.2x107 0.3x107

0.2x107 0.3x107

ABSENT ABSENT

1.00 1.50

0.4x109 0.3x106

0.1x108 0.3x106

0.3x109 0.1x105

0.50

0.3x109

0.3x107

ABSENT

1.00 1.50 0.50

7

0.1x107 0.2x109 0.3x107

0.3x107 ABSENT ABSENT

2

D12

3.00

3

D21

1.00

4

5

D22

D31

3.00

1.0

0.4x10 0.2x109 0.3x108

observed to be in low range. Potassium is important in Photosynthesis process. Available potassium is medium to high .The Results of analysis of Macro and micro nutrients and the Total count, faecal count and E-coli count is presented in the table.5 and 6. It is found that the E-coli bacteria travelled horizontally up to 3 m in downstream side of pit. The soil at Kanakapura site was sandy soils. These sites have organic content varying from 0.09 to 0.66 %. The soils were Acidic to alkaline with PH varying from 5.8 to 9.3. The Electrical Conductivity is in the range of 0.06-0.39 and organic content is low (Measures of Nitrogen). In the study area Phosphorus is observed to be in low range. Available potassium is low to high. The Results of analysis of Macro and micro nutrients and the Total count, faecal count and E-coli count is presented in the table.7, and 8.It is found that the E-coli bacteria travelled horizontally up to 5 m in downstream side of pit in Pre monsoon Season Table 7. Bacteriological Analysis of soil, Kanakapura (Pre-Monsoon season) SL NO

Sample point

Horizontal distance (M)

Depth (M)

Total count CFU/100ml

Fecal count CFU/100ml

E-Coli CFU/100ml

1

K11

1.00

0.50

1.3x108

ABSENT

0.4x105

0.75 0.50

7

0.8x10 0.6x108

ABSENT ABSENT

0.2x103 0.6x104

0.75

0.4x105

ABSENT

0.1x103

0.50

1.5x107

ABSENT

0.1x108

0.75

1.1x108

ABSENT

0.3x108

0.50

0.9x106

ABSENT

0.4x105

0.75 1.50

0.8x105 1.1x104

ABSENT ABSENT

0.7x104 0.9x103

0.50

2.4x109

0.1x107

1.1X103

0.75

6

0.2x104

1.6x104

0.50 0.75

4

1.0x10 1.3x106

ABSENT ABSENT

0.4x106 0.5x104

1.50

0.6x109

ABSENT

0.2x103

0.50

5

ABSENT

0.05x105

2

K12

3.00

3

K21

1,00

K22

4

K31 K32

5.

K41

3.00

3.00 5.00

3.00

3.0x10

0.9x10

6. Conclusion The results of analysis of bore well water samples collected near the onsite sanitation systems contains high values of chloride Total Dissolved Solids, and nitrate indicates the contamination of groundwater by onsite

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sanitation systems. Among these chloride,Total Dissolved Solids are very high and are exceding the permissible limit. In study area 75% of samples are having maximum values of dissolved solids and are exceeding WHO Guideline of 1000mg/l. The bore well water is not good for drinking purpose and is unpalatable. The study reveals Nitrate contamination in most of the samples.The Nitrate contamination is more during post monsoon compared to other seasons. The high concentration of chloride and nitrate are observed in Bore well sample shows that the Groundwater is contaminated from the Leachate from the onsite sanitation systems. The chloride and nitrate is found in Bore wells up to 50m from the onsite sanitation system. In kanakapura groundwater occurs in unconfined or water table conditions and it occurs in semi confined to confined conditions in fractured formations at deeper depths. The thickness of weathering in major parts is 5-10m and more than 10m in rest of the area. Table 8. Soil Analysis report for Physico- Chemical, Macro and Micro Nutrients (Kanakapura). Macro Nutrients SL NO

Sample point

1

K11

1.00

2

K12

3.00

3

K21

1,00

K22

3.00

K31

3.00

K32

5.00

K41

3.00

4

5.

Horizontal distance(M)

Vertical Depth (M) 0.50 0.75 0.50 0.75 0.50 0.75 0.50 0.75 1.50 0.50 0.75 0.50 0.75 1.50 0.50 0.75

PH

8.70 8.80 8.80 8.80 8.60 8.70 8.20 8.80 5.80 6.80 6.80 6,10 6.60 6.70 8.80 9.30

EC (Dsm)

OC (%)

P205 Kg/ha

K20 Kg/ha

0.24 0.19 0.18 0.17 0.32 0.27 0.39 0.29 0.09 0.21 0.20 0.06 0.16 0.17 0.19 0.24

0.09 0.35 0.17 0.30 0.37 0.26 0.66 0.26 0.34 0.58 0.34 0.44 0.39 0.41 0.15 0.23

09 11 26 44 21 19 64 13 17 43 34 08 27 56 25 11

20 20 212 270 84 36 463 33 70 38 23 26 25 22 181 940

Micro Nutrients(ppm) Zn

Cu

Mn

Fe

Br

0.494 0.484 0.650 0.698 0.504 0.618 2.030 0.148 0.224 0.654 0.812 0.124 0.750 0.626 0.408 1.010

0.414 0.378 0.344 0.534 0.570 0.401 1.490 0.136 0.552 0.830 0.900 0.830 0.796 0.864 0.622 0.466

2.198 3.276 3.784 5.002 3.584 3.814 3.830 3.984 15.97 17.04 17.13 17.57 17.84 17.28 3.830 2.860

2.776 3.501 5.380 3.554 2.964 1.112 6.238 7.582 8.360 9.569 10.67 7.420 11.47 10.20 2.508 4.144

0.18 0.38 0.38 0.40 0.18 0.13 0.40 0.42 0.26 0.44 0.82 1.02 0.34 0.46 0.44 0.38

The groundwater is taped in unconfined and semi unconfined aquifer system. The fracture and joints are the potential pathways for migration of contaminats. In fractured hard rocks leachate movement is faster. Hence chances of saturated zone contamination from onsite sanitation systems are more In addition to the above the agricultural lands are very close to study areas. This may be cause for more concentration of Nitrate in those areas. This can be justified with findings of Central groundwater board that High concentration of nitrate >45mg/l is observed in the major part of area.(CGWB2013). In Doddaballapura the groundwater is taped in deep confined aquifer system compared to kanakapura town and agricultural lands also far away from the study area. Hence the Nitrate concentration is less compared to kanakapura town. During study it was observed that disposal of septic tank effluents along with sullage water in open drains may be responsible for more groundwater contamination. It is found that presence of total coli is observed in all stations of both towns. The result of bacterial analysis indicates that water should be chlorinated before its use for drinking. The soil samples analysis indicated that Microbial impact up to 3m and 5m from onsite sanitation system in Doddaballapura town and Kanakapura town during pre monsoon period. Acknowledgements Authors express their sincere thanks to Principal and Management of Dayananda Sagar College of Engineering , Bangalore, for providing facilities and their encouragement. Authors also thanks Belmagi Chief chemist zuari-

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agrochemicals and Sneha test house(NABLaccreidated lab) for their support in carrying out analysis of samples. References APHA (American Public Health Association) 2003, Standard methods for examination of water and wastewater specifications, 19th Edition, Washington.D.C. ARGOSS, 2001. Guidelines for assessing the risk to groundwater from on-site sanitation. BGS Report CR/01/142, Key worth. Banerjee G. 2011:Underground pollution travel from leach pits of on-site sanitation facilities: a case study. Clean Technol Envir 13(3) 489-497. Groundwater information booklet.2013 Ramanagaram and Bangalore Rural Districts Central ground water board. Jay.P.Graham,et,al. 2013. Pit Latrines and impacts on groundwater quality; A systematic Review. Environ Health Perspect121. 521-530. Lawrence, A. R., Macdonald, D. M. J., Howard, A. G. Barret, M. H., Pedley, S., Ahmed, K. M., et al. (2001) Guidelines for assessing the risk of groundwater from on-site sanitation. Commissioned report (CR/01/142) of British Geological Survey. Lewis, W. J., S. S. D. Foster, et al. 1980. The risk of groundwater pollution by on-site sanitation in developing countries: A literature review, International Reference Centre for Wastes Disposal. NEERI.2005.Impact of on-site sanitation systems on quality of groundwater and surface water sources submitted to CPHEEO-WHO. New Delhi. Pujari PR, Padmakar C, Labhasetwar PK, Mahore P, Ganguly AK. 2012 Assessment of the impact of on-site sanitation systems on Groundwater pollution in two diverse geological settings--a case study from India. Environ Monit. Assess 184(1), 251-263. Rao, Sudhakar M and Sekhar, M and Rao, Raghuveer P 2013 Impact of pit-toilet leachate on groundwater chemistry and role of vadose zone in removal of nitrate and E-coli pollutants in Kolar District, Karnataka, India. In Environmental Earth Sciences, 68 (4). pp. 927-938. Ramaraju H. K. 2009 Integrated assessment of risk for contaminated sites due to on-site sanitation systems in mining area, Karnataka, India Proc. of Symposium JS.2 at the Joint IAHS & IAH Convention, Hyderabad, India, IAHS Publ. 329. WHO (World Health Organization) 1993.Guidelines for drinking water quality, 2nd Edition, Geneva: Switzerland