Table 4.

Physical and chemical analyses of monitoring well samples at Alexandria’s solid waste sanitary landfills, Egypt.

Parameters	Unit	Well 1				Well 2
n = 12		Min	Max	$\overline{x}\pm \text{SD}$	p-Value	Min	Max	$\overline{x}\pm \text{SD}$	p-Value
PH	–	7.4	8.8	–	–	7.12	8.1	–	–
Conductivity	μS/cm	4200	21,500	12745 ± 120	.000⁎	3720	16,800	10354 ± 76	.000⁎
Total dissolved solids	mg/l	3263	16,276	9895 ± 93	.000⁎	2855	14,781	8721 ± 58	.000⁎
Chlorides	mg/l	2240	11,750	6890 ± 45	.000⁎	1030	8200	4685 ± 30	.000⁎
Total suspended solids	mg/l	682	1591	1197 ± 29	.002⁎	180	1348	867 ± 16	.000⁎
Chemical oxygen demand	mg/l	78	190	80 ± 5	.000⁎	45	120	68 ± 2	.000⁎
Biochemical oxygen demand	mg/l	36	95	60 ± 1	.000⁎	16	78	45 ± 1	.000⁎
Total nitrogen	mg/l	1.0	1.7	1.3 ± 0.1	.007⁎	0.9	1.4	1.10 ± 0.09	.001⁎
Ammonia-N	mg/l	1.2	5.1	1.7 ± 0.9	.000⁎	0.14	0.55	0.28 ± 0.06	.006⁎
Nitrate-N	mg/l	0.22	0.36	0.25 ± 0.07	.043	0.05	0.24	0.13 ± 0.02	.075
Sulfates	mg/l	647	1100	784 ± 42	.004⁎	240	900	543 ± 31	.439
Phosphates	mg/l	0.08	0.15	0.10 ± 0.06	.423	0.02	0.09	0.05 ± 0.01	.124
Oil and grease	mg/l	ND†	ND†	ND†	–	ND†	ND†	ND†	–

95% CI = 1.96.

^⁎Significant at p ⩽ 0.05.

^†ND: Not Detected; the detection level was 0.06 mg/l.