% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/PEC_sw_exposit_runoff.R
\name{PEC_sw_exposit_drainage}
\alias{PEC_sw_exposit_drainage}
\title{Calculate PEC surface water due to drainage as in Exposit 3}
\source{
Excel 3.02 spreadsheet available from
\url{https://www.bvl.bund.de/SharedDocs/Downloads/04_Pflanzenschutzmittel/zul_umwelt_exposit.html}
}
\usage{
PEC_sw_exposit_drainage(
  rate,
  interception = 0,
  Koc = NA,
  mobility = c(NA, "low", "high"),
  DT50 = Inf,
  t_drainage = 3,
  V_ditch = 30,
  V_drainage = c(spring = 10, autumn = 100),
  dilution = 2
)
}
\arguments{
\item{rate}{The application rate in g/ha}

\item{interception}{The fraction intercepted by the crop}

\item{Koc}{The sorption coefficient to soil organic carbon used to determine the mobility. A trigger
value of 550 L/kg is used in order to decide if Koc >> 500.}

\item{mobility}{Overrides what is determined from the Koc.}

\item{DT50}{The soil half-life in days}

\item{t_drainage}{The time between application and the drainage event, where degradation occurs, in days}

\item{V_ditch}{The volume of the ditch is assumed to be 1 m * 100 m * 30 cm = 30 m3}

\item{V_drainage}{The drainage volume, equivalent to 1 mm precipitation on 1 ha for spring/summer or 10 mm for
autumn/winter/early spring.}

\item{dilution}{The dilution factor}
}
\value{
A list containing the following components
\describe{
\item{perc_runoff}{The runoff percentages for dissolved and bound substance}
\item{runoff}{A matrix containing dissolved and bound input for the different distances}
\item{PEC_sw_runoff}{A matrix containing PEC values for dissolved and bound substance
for the different distances. If the rate was given in g/ha, the PECsw are in microg/L.}
}
}
\description{
This is a reimplementation of the calculation described in the Exposit 3.02 spreadsheet file,
in the worksheet "Konzept Drainage". Although there are four groups of
compounds ("Gefährdungsgruppen"), only one distinction is made in the
calculations, between compounds with low mobility (group 1) and compounds
with modest to high mobility (groups 2, 3 and 4). In this implementation,
the group is derived only from the Koc, if not given explicitly. For
details, see the discussion of the function arguments below.
}
\examples{
  PEC_sw_exposit_drainage(500, Koc = 150)
}
\seealso{
\code{\link{perc_runoff_exposit}} for runoff loss percentages and \code{\link{perc_runoff_reduction_exposit}} for runoff reduction percentages used
}