Table 1.

Characteristics of oil field formation water and the required specifications for its disposal and reuse.

Characteristics of oil field formation water	Values	Permissible Limits for formation water disposal and reuse
		On-shore disposal (Environment (Protection Rules, 1986)	Disposal by reinjection into abandoned oil well (Environment Protection Rules, 1986)	Reuse by reinjection into oil reservoirs (Recommendation Standard and Analysis Method for the Clastic Rock Reservoir Injection Water Quality)
pH	8.35	5.5–9.0	No prescribed lower limit	No prescribed lower limit
TPH (mg L−1)	115	10	10	<5.0
SO4 (mg L−1)	48	1000	No prescribed lower limit	No prescribed lower limit. Low Sulfate/sulfate free water is desirable for reinjection (Jordan et al. 2008; Bader 2007)
COD (mg L−1)	316.80	100	No prescribed lower limit	No prescribed lower limit
Fe (mg L−1)	2.2746	3	No prescribed lower limit	No prescribed lower limit
Cu (mg L−1)	0.0066	0.05	No prescribed lower limit	No prescribed lower limit
Cr (mg L−1)	0.0393	0.1	No prescribed lower limit	No prescribed lower limit
Zn (mg L−1)	0.1763	0.1	No prescribed lower limit	No prescribed lower limit
Ni (mg L−1)	0.2631	3	No prescribed lower limit	No prescribed lower limit
Pb (mg L−1)	Not detected	0.1	No prescribed lower limit	No prescribed lower limit
Na (mg L−1)	42.0972	No prescribed lower limit	No prescribed lower limit	No prescribed lower limit
Mn (mg L−1)	0.0105	No prescribed lower limit	No prescribed lower limit	No prescribed lower limit
Ca (mg L−1)	289.7853	No prescribed lower limit	No prescribed lower limit	No prescribed lower limit
K (mg L−1)	Not detected	No prescribed lower limit	No prescribed lower limit	No prescribed lower limit
Mg (mg L−1)	10.374	No prescribed lower limit	No prescribed lower limit	No prescribed lower limit
N (mg L−1)	3.5	No prescribed lower limit	No prescribed lower limit	No prescribed lower limit