Arsenic concentrations (ppb) at three background wells and one compliance well (six monthly samples for each well; first four missing at compliance well). Nondetects reported as <5.

EPA.92c.arsenic2.df

Format

A data frame with 24 observations on the following 6 variables.

Arsenic.orig

a character vector of original arsenic concentrations (ppb)

Arsenic

a numeric vector of arsenic concentrations with <5 coded as 5

Censored

a logical vector indicating which observations are censored

Month

a factor indicating the month of collection

Well

a factor indicating the well number

Well.type

a factor indicating the well type (background vs. compliance)

Source

USEPA. (1992c). Statistical Analysis of Ground-Water Monitoring Data at RCRA Facilities: Addendum to Interim Final Guidance. Office of Solid Waste, U.S. Environmental Protection Agency, Washington, D.C. p.60.