Chloride concentrations (ppm) collected over a five-year period at a solid waste landfill.
A data frame with 19 observations on the following 4 variables.
a Date object indicating the date of collection
a numeric vector of chloride concentrations (ppm)
a numeric vector indicating the number of days since January 1, 2002
a numeric vector of residuals from a linear regression trend fit
USEPA. (2009). Statistical Analysis of Groundwater Monitoring Data at RCRA Facilities, Unified Guidance. EPA 530/R-09-007, March 2009. Office of Resource Conservation and Recovery Program Implementation and Information Division. U.S. Environmental Protection Agency, Washington, D.C. p.17-26.
USEPA. (2010). Errata Sheet - March 2009 Unified Guidance. EPA 530/R-09-007a, August 9, 2010. Office of Resource Conservation and Recovery, Program Information and Implementation Division. U.S. Environmental Protection Agency, Washington, D.C.