TABLE 2.

Decay rates of MS2 phage, GA phage, and human adenovirus 2 in raw groundwater at 4 and 20°C

Virus	Temp (°C)	Cell culture					Real-time RT-PCR
		Slope	P valuea	Decay rate (%/day)	T90 (days)	95% confidence limit (days)	Slope	P valuea	Decay rate (%/day)	T90 (days)	95% confidence limits (days)
MS2 phage	4	−0.0428	<10−4	9.4	23.4	22.5; 24.2	−0.0029	<10−4	0.7	344.8	323.9; 365.7
	20	−0.7195	<10−4	80.9	1.4	1.1; 1.6	−0.1166	<10−4	23.5	8.6	8.1; 9.0
GA phage	4	−0.0503	<10−4	10.9	19.9	19.1; 20.7	−0.0004	0.019	0.1	2,500.0	109.9; 4,890.1
	20	−0.8081	<10−4	84.4	1.2	1.1; 1.3	−0.0278	<10−4	6.2	35.9	32.8; 39.2
HAdV2	4	−0.0076	<10−4	1.7	131.6	100.7; 162.8	NSb
	20	−0.0279	<10−4	6.2	35.6	33.3; 38.4	−0.0036	<10−4	0.8	278.0	193.3; 362.2

^aNote that use of the Bonferroni correction has only a slight effect on the outcome of the multiple testing procedure displayed in the table, since the slopes of the fitted models (excepting the GA genome at 4°C) remain highly significantly different from 0.

^bNS, slope value was not significantly different from 0.