Table 2.

Descriptive statistics of coliform bacteria, Escherichia coli, and nitrate concentrations.

Sampling period	Measurement	Number of positive samples	Number of non-detects	Concentration of positive samplesa
				Mean	Median	Minimum	25th percentile	75th percentile	Maximumb
Groundwater recharge	Coliforms	87	232	73.2	5.2	1.0	2.0	17.3	$>\mathrm{2,419.6}$
	E. coli	5	314	5.0	2.0	1.0	2.0	4.1	16.1
	Nitrate-N	203	119	6.3	4.7	0.2	1.6	9.0	29.7
No groundwater recharge	Coliforms	87	310	116.8	6.2	1.0	2.0	55.4	$>\mathrm{2,419.6}$
	E. coli	10	387	105.0	3.1	1.0	1.3	8.8	1011.2
	Nitrate-N	205	196	6.5	5.2	0.2	2.1	9.1	33.3

Note: MPN, most probable number.

^aColiforms and E. coli, $\text{MPN}/100\mathrm{mL}$; nitrate-N, mg/L.

^b2,419.6 $\text{MPN}/100\mathrm{mL}$ was the upper limit of quantification.