Either install the stable version from CRAN or install the latest development version from GitHub.
install.packages(pkgs="RAQSAPI", dependencies = TRUE )To install the development version of RAQSAPI, first if not already installed, install the remotes package and its dependencies. Then run the following in a R environment.
remotes::install_github(repo = "USEPA/raqsapi",
                        dependencies = TRUE,
                        upgrade = "always",
                        build = TRUE,
                        #optional, set TRUE if the manual is desired,
                        #requires pandoc
                        build_manual = FALSE,
                        build_vignettes = TRUE 
                        )