Ammonia nitrogen (NH\(_3\)—N) concentration (mg/L) in the Skagit River measured monthly from January 1978 through December 2010 at the Marblemount, Washington monitoring station.

Skagit.NH3_N.df

Format

A data frame with 396 observations on the following 6 variables.

Date

Date of collection.

NH3_N.Orig.mg.per.L

a character vector of the ammonia nitrogen concentrations where values for non-detects are preceeded with the less-than sign (<).

NH3_N.mg.per.L

a numeric vector of ammonia nitrogen concentrations; non-detects have been coded to their detection limit.

DQ1

factor of data qualifier values.

  • U = The analyte was not detected at or above the reported result.

  • J = The analyte was positively identified. The associated numerical result is an estimate.

  • UJ = The analyte was not detected at or above the reported estimated result.

DQ2

factor of data qualifier values. An asterisk (*) indicates a possible quality problem for the result.

Censored

a logical vector indicating which observations are censored.

Details

Station 04A100 - Skagit R \@ Marblemount. Located at the bridge on the Casdace River Road where Highway 20 (North Cascades Highway) turns 90 degrees in Marblemount.