Table 1 Results of groundwater chemical analyses at the date of sampling—general water chemistry and the concentration of main petroleum hydrocarbons are shown

Specific electrical conductivity

μS cm⁻¹

1360

Redox potential

mV

− 19

Dissolved oxygen

mg l⁻¹

0.8

pH

–

6.5

Temperature

°C

13

SO₄²⁻

mg l⁻¹

< 30

NO₃^¯

mg l⁻¹

< 5

Fe(II)

mg l⁻¹

9.4

Mn(II)

mg l⁻¹

4.6

TPHs^a

mg l⁻¹

1.9

Benzene

mg l⁻¹

0.1

Toluene

mg l⁻¹

0.009

Ethylbenzene

mg l⁻¹

0.8

Xylenes

mg l⁻¹

3.2

Other alkyl benzenes

mg l⁻¹

7.2