Benzene concentrations (ppm) at one background and five compliance wells (four monthly samples for each well).
EPA.89b.benzene.dfA data frame with 24 observations on the following 6 variables.
Benzene.origa character vector of the original observations
Benzenea numeric vector with <1 observations coded as 1
Censoreda logical vector indicating which observations are censored
Montha factor indicating the month of collection
Wella factor indicating the well number
Well.typea factor indicating the well type (background vs. compliance)