8.1 Bio-Physico-Chemical Parameters
 

1. Dissolved Oxygen

 2. Carbon Dioxide level

 3. pH

 4. Turbidity

5. Hydro Carbon (petroleum) content of soil
 

8. 2 Water Test [Surface]

The crude oil samples obtained from the spill source was determined and has the following key approximate physical properties (obtained at water surface and therefore could vary).
 

 a. Viscosity  =  97.05kg/m.h

 b. Density tension  =  830.00kg/m³

 c. Surface tension  =  0.0320n/m

 d. Cohesion force  =  0.0600n/m

 e. Adhesive force = 0.6500n/m

 f. Viscosity of oil/water ratio = 2.445
 

 These results show the fast spreading rate of the crude oil once discharged into the aquatic environment.
 

8.3 WATER TEST [Fish Ponds]

 Water samples were collected from fishponds within the area under review to Analyse the desired parameter. Tests were carried out at intervals of 2 weeks.
 

8.3. 1. Period of inspection.
 
 

A	=	1st test results 29th January - 12th February 1998
B	=	2nd test results 13th February - 27th February 1998
C	=	3rd test results 28th February - 13th March 1998

8.3.2. pH:  The pH values for the last test results were on the basis of average per sample.

  Mean   =   4.0 + 3.7 + 3.5 + 3.8 + 4.2 + 4.4 = 3.9

 The relationship between pH to pond fish culture is summarized below.
 
 

Death                             Slow growth            Good growth               Slow growth             Death

4

5                      6

7                     8

9                  10

11

 Fig: Effect of pH on pond fish (swingle, 1969).
 

 In comparison, the value of 3.9 obtained from the result shows a slight decrease from acceptable fish survival limit.
 

8.3.3 ALKALINITY

The term alkalinity refers to the total concentration of   bases in water expressed in milligram per litre equivalent to the   carbonate.

 Alkalinity measurement ranged between 95 - 130, thus depicting a   fluctuating yield.

Total Alkalinity (mg/l)                         No. ponds                                        Average Yield kg/ha

8 - 20	7	19
21 - 40	7	32
41 - 80	20	71
81 - 120	15	70
>120	20	54

Fig: Annual yield of yellow pikeperch (stizostedron vitereum) in ponds with waters of different total alkalinities (Moyle, 1946).
 

8.3.4 DISSOLVED OXYGEN

The BOD level in the waters analysed show decrease in the universally accepted level for fish survival.
 
 

A	0.8	0.9	0.7	1.2	0.9	0.9
B	1.2	1.0	0.7	0.9	0.7	0.8
C	0.9	0.9	1.0	0.8	1.0	0.9

  ,
 

A

=

5.4

B

=

5.3

C

=

5.5

T	=	A + B + C	=	5.4+ 5.3 + 5.5
	=	16.2
C	=	(16.2)² 3 X 6	=	262.4   18	=	14.57
	=	14.6

yij² = (0.8)² + (0.9)² + (0.7)² +(1.2)² +(0.9)²+ (0.9)²+(1.2)² + (1.0)² + (0.7)² + (0.9)² + (0.7)² +
            0.8)²  +  (0.9)² + (0.9)² + (1.0)² + (0.8)² + (1.0)² + (0.9)²

       = 0.64 + 0.81 + 0.49 + 1.44 + 0.81+ 1.44 + 1 + 0.49+ 0.81 + 0.49 +0.64 + 0.81+  0.81 + 1 +
          0.64 + 1 + 0.84

       = 14.97

SST  = 14.97 - 14.6  =  0.37
 
 
 

T1²   n

=

(5.4)² + (5.2)² + (5.5)²                           6

=

87.5   6

=

14.58

 

SS(Tr)	=	14.58 - 14.57	=	0.01
SSE	=	0.37 - 0.01	=	0.36
K - 1	=	3 - 1	=	2
K(n-1)	=	3(6 - 1)	=	15
NK - 1	=	18 - 1	=	17
Ms(Tr)	=	0.01   2	=	5 x 10-3
MSE	=	0.36   15	=	2.4 x 102
F	=	5 x 10-3 2.4 x 10-2	=	0.2

Calculated F value is far less than tabulated values at 99%, 95%, 90%, 85%, 80%, 70%, 75% confidence level. Therefore, the authenticity of the sampling method is very high.
 

8.3.5 Anova: Determining water sampling method relative to fish survival (oxygen count, BOD).
 
 

Source of Error	Df	SS	Ms	F
Samples	2	0.01	5 x 10-3	0.2
Error	15	0.36	2.4 x 10-2
Total	17	0.37

NOTE: This results in a slight decrease in the universally accepted value of 1mg/litre for fish survival. Thus some specie of fish will definitely die of the spill.

8.3.6 CARBON DIOXIDE LEVEL:

Measurement here are in parts per million (PPm)
 
 

A	60	50	72	100	78	50
B	65	84	75	105	80	69
C	80	90	80	105	85	77

 

A

=

410

B

=

478

C

=

517

 

T	=	410 + 478 + 517	=	1405
C	=	(1405)²      18	=	109668.06

Y²ij      =   (60)2 +(50)² +(72)² + (100)² + (78)² + (50)²+ (65)² + (84)² + (75)² + (105)² +
                  (80)² + (90)² + (80)² + (105)² + (85)² + (77)²

            = 3600 + 2500 + 5184 + 10000 + 6084 + 2500 + 4225 + 7056 + 11025 + 6400 + 4761 +
                 6400 +8100 + 6400 + 11025 + 7225 + 5929

            = 114039

SST       = 114039 - 109668.06  =  4370.94

 T²         = (410)² + (478)² + (517)²   =  110645.5
  n                                 6

 SS(Tr)   =  110645.5 - 109668.06      =  977.44

 SSE       =  4370.94 - 977.44  =  3393.5

K - 1      =     2,  Kn - 1             =     15, nK - 1 = 17

Ms(Tr)    =    977.44                =    488.72
                          2

MSE       =    3393.5                 =    226.23
                         15

F            =    488.72                  =    2.16
                    226.23

Calculated value highly feasible at even 50% confidence levels.
 

8.3.7. Anova: Determining carbon dioxide count relative to fish survival
 
 

Source of Error	Df	SS	Ms	F
Samples	2	977.44	488.72	2.16
Error	15	3393.5	226.23
Total	7	4370.94

8.4 SOIL TEST (RIVER BANKS)

 Gravimetric analysis was used to determine amount of petroleum in a given sample using Benzene as solvent. Soil samples were collected at the sites using the riverbanks as the focal points.
 
 

Samples	Top Soil (mg/m)	25cm depth Soil (mg/m)
A	70	75
B	50	60
C	101	-
D	89	94
E	76	85
F	63	70

To determine whether there exist some significance in the amount of petroleum at various sites, the F-test was determined.

Let top soil be X0

Let 25cm depth soil be X1
 

Xo	=	449		X1	=	384
Xo	=	449   6		X1	=	384   5
	=	74.8			=	77
(X - Xo)²	=	1267		(X - X1)²	=	695
F(Vo,V1)	=	So2 S12
So²	=	(Xo - X1)²        n	=	1267   6-1	=	253.4
S1²	=	(X0 - X1)²	=	695  5-1	=	173.75

The tabulated F value for Vo = 5 and V1 = 4 is 6.25

F expt   =  253.4      =  1046
                 173.75

F expt < F crit

This value of F was tested at various confidence levels to be extremely accurate.
 

8.5. pH

The pH values for the above tests were determined on the basis of average per sample.
 

8.6. Turbidity:

The turbidity of the waters analysed show a very sharp rate. Since fish survive better in clean water, it could be deduced that fish survival in the affected area is impossible.