Trend analysis results for ions and color April 1983 April 2014
  Increase Decrease No change
Mg 2 4 19
Si 0 5 20
Mn 0 3 22
Fe 0 5 20
Cu 0 4 20
Al 0 7 18
Ca 3 6 16
Na 7 0 18
K 5 0 20
Cl 11 0 14
NO3 1 0 24
SO4 1 21 3
color 21 0 4
SOURCE: ACID RAIN MONITORING PROJECT ANNUAL REPORT