Icph presentation with comments from novil

CHUNNAKAM POWER PLANT: A POINT SOURCE OF OIL CONTAMINATION OF WELLS? Dr.NWANY Wijesekara, Registrar in Community Medicine Dr. V Murali, Consultant Community Physician, Ministry of Health Dr. HDB Herath, Deputy Director (Environmental Health), Ministry of Health

International Conference on Pubic Health, Colombo 2015

INTRODUCTION CHUNNAKAM IS LOCATED IN THE JAFFNA PENINSULA AT THE NORTH OF SRI LANKA

International Conference in Pubic Health, Colombo 2015

INTRODUCTION

(CONTINUED)

• Jaffna Peninsula solely depend on underground water supply provided by 4 aquifers

International Conference in Pubic Health, Colombo 2015

INTRODUCTION (CONTINUED) MASS PROTESTS WERE HELD ALLEGING THAT A PRIVATE POWER PLANT LOCATED AT THE PREMISES OF THE ELECTRICITY BOARD CAUSING UNDERGROUND WATER POLLUTION

BY WASTE OIL AND GREASE

International Conference in Pubic Health, Colombo 2015

INTRODUCTION (CONTINUED) QUARTER MILLION PEOPLE ARE AFFECTED

International Conference in Pubic Health, Colombo 2015

INTRODUCTION

• A study done by National Water Supply & Drainage Board (NWSDB), Jaffna between 2013 and 2014 was in favour of a source located in Chunnakam Area.

International Conference in Pubic Health, Colombo 2015

(CONTINUED)

INTRODUCTION

(CONTINUED)

Who are the possible culprits for this pollution in Chunnakam area?

1. Northern Power Plant, hired by the CEB ?

2. Abandoned Power Plant (Agrico) at the same premises earlier hired by the CEB ?

3. Uthuru Janani Power Plant operated by the CEB ?

4. Any other sources of pollution in Chunnakam?

International Conference in Pubic Health, Colombo 2015

INTRODUCTION (CONTINUED) THE PRIVATE COMPANY INVOLVED IN POWER GENERATION AT NORTHERN POWER PLANT HAS DENIED ALLEGATIONS OF CAUSING POLLUTION

International Conference in Pubic Health, Colombo 2015

JUSTIFICATION

• It is important to locate the source of contamination to propose suitable remedial measures.

International Conference in Pubic Health, Colombo 2015

OBJECTIVE

• To determine whether the Chunnakam Power Plant could be a point source for this contamination.

International Conference in Pubic Health, Colombo 2015

METHODOLOGY

• Secondary data presented in the report of the (NWSDB, Jaffna) was used in this analysis.

International Conference in Pubic Health, Colombo 2015

METHODOLOGY

(CONTINUED)

•Samples obtained from three zones “within 200m” and “200m to 500 m” and “500m to 2000m” • Two by two tables were developed by calculating the number above or below the Maximum Permissible Limits (MPL) using the above results.

• The Chi Square Statistic (χ2) with p value of 0.05 and Odds Ratio (OR) with 95% Confidence Interval (95% CI) between International Conference in Pubic were Health, Colombo 2015 different zones calculated.

METHODOLOGY

(CONTINUED)

International Conference in Pubic Health, Colombo 2015

Results

Zones

Number of wells examined

Number of wells with oil above the Maximum Permissible Limits

Within 200m

67

54 (81%)

200m to 500m

42

31 (74%)

500m to 2000m

41

21 (51%)

International Conference in Pubic Health, Colombo 2015

RESULTS

(continued)

Zones compared

X 2 with relevant p values

Odds Ratio

95 % Confidence Interval

Within 200m and 200m to 500 m

1 . 4 1 (p=0 . 0 5 9 )

1.47

(0 . 0 5 9 -3 . 6 9 )

2 0 0 m to 5 0 0 m and 5 0 0 m to 2 0 0 0 m

4 . 5 2 (p=0 . 0 1 7 )

2.68

(1 . 0 7 -6 . 7 4 )

within 2 0 0 m and 5 0 0 m to 2 0 0 0 m

1 0 . 3 5 (p= 0 . 0 0 0 6 5 )

3.96

(1 . 6 7 -9 . 3 6 )

International Conference in Pubic Health, Colombo 2015 https://www.medcalc.net/tests/odds_ratio.php

CONCLUSIONS • The percentage of well exceeding the MPL has shown a decrease with the distance from the CPP. • There was no statistical significance between the proportion of wells exceeding MPL between within 200m and 200-500m (X2 =1.41, p=0.059).

• This was evident from the OR as well (1.47, 95% CI 0.059-3.69). This may be due to within 200m and 200m-500m zones being equally contaminated or being saturated.

International Conference in Pubic Health, Colombo 2015

CONCLUSIONS

(continued)

• There was statistically significant decrease of number of wells with more than MPL from 200m-500m to 500m-2000m zones and within 200m and 500m-2000m zones.

• For the above pairs of zones, the OR was 2.68 (95% CI 1.069-6.74) and 3.96 (95% CI 1.67-9.36) respectively.

• The level of oil contamination appears to be uniform up to 500m from the CPP. However, this appears to be decreasing from there onwards up to 2000m.

• This analysis favors a point source to be located within the CPP area.

International Conference in Pubic Health, Colombo 2015

RECOMMENDATIONS • Based on the above conclusions the CEB premises should be examined for any remaining pollutants ( waste oil) and the remaining pollutants need to be removed and disposed without causing environmental pollution. • Ensure that the waste products by the operation of power plants in future are properly disposed without contaminating the underground water further.

International Conference in Pubic Health, Colombo 2015