samples: Water-Quality Data Records
In inldata: Collection of Datasets for the USGS-INL Aquifer Monitoring Networks

Description Usage Format Source References Examples

Water-quality data from laboratory analyses of groundwater samples collected from wells in the U.S. Geological Survey (USGS) water-quality monitoring network, Idaho National Laboratory and vicinity, Idaho. Data was obtained from the National Water Information System (U.S. Geological Survey, 2019).

samples

A data frame with 159,554 records and 19 variables:

site_no: USGS site identification number
sample_dt: date sample was collected
medium_cd: 3-digit medium code that identifies the material type and quality assurance type of the sample. The codes and their meanings are: "WG" water below land surface contained in the saturated zone (groundwater); and "WGQ" groundwater quality-control (QC) sample.
db_no: 2-digit NWIS database number. The codes and their meanings are: "01" is the environmental database, and "10" is the quality-assurance (QA) database.
anl_ent_cd: analyzing entity code of the organizational unit that performed the sample analysis used to obtain the result.
parm_cd: USGS 5-digit parameter code. For example, the parameter code for Tritium is "07000".
remark_cd: 1-digit remark code (result level) used to qualify the parameter value. The codes and their meanings are: "" quantified value. "<" actual value is known to be less than the value reported, that is, the measured concentration is below the reporting limit (RL) and represented as a censored (or nondetection) value. For censored values, the value reported is the RL. "E" value is estimated, that is, the actual value is greater than the minimum detection limit (MDL) and less than the laboratory reporting level (LRL). "R" nondetect, result less than sample-specific critical level. "U" material specifically analyzed for but not detected. "V" value affected by contamination.
result_va: parameter value; see parameter_units variable in the parameters dataset for the units of measurement.
lab_std_dev_va: laboratory standard deviation (SD). For radiochemical data, SD is determined from the counting error. Prior to January 1, 2018, counting error was reported as two SD, therefore, these values were divied by 2.
dqi_cd: 1-digit data quality indicator code that indicates the review status of a result. The codes and their meanings are: "A" historical data, "S" presumed satisfactory, and "R" reviewed and accepted.
rpt_lev_va: laboratory reporting limit in effect for the parameter and method at the time the measurement was made.
rpt_lev_cd: reporting level code that identifies the analytical reporting level appropriate for the analytical method. The codes and their meanings are: "DLBLK" detection limit by blank data; "DLDQC" detection limit by DQCALC, lowest concentration that with 90 percent confidence will be exceeded no more than 1 percent of the time when a blank sample is measured; "IRL" interim reporting level, a temporary reporting level; "LRL" laboratory reporting level, equal to twice the yearly-determined LT-MDL; "LT-MDL" long-term method detection limit, a detection level derived by determining the standard deviation of a minimum of 24 MDL spike sample measurements over an extended period of time; "MDL" method detection limit, minimum concentration of a substance that can be measured and reported with a 99 percent confidence that the analyte concentration in greater than zero; "PQL" practical quantitation limits; "MRL" minimum reporting level, smallest measured concentration that can be reliably measured using a given analytical method; "RLDQC" reporting limit by DQCALC, is greater than or equal to two times the DLDQC; "SSLC" sample-specific critical level, the calculated and reported value is below which the radiochemistry result is considered a non-detect; and "SSMDC" sample-specific minimum detectable concentration, a reporting level that varies for each sample and is primarily used in radiochemical analyses.
samp_type_cd: 1-digit sample type code that identifies the QA type of a sample. The codes and their meanings are: "H" samples collected over a period of time (composite); "2" samples prepared from a reference material where none of the analytes of interest are present in detectable quantities (blank); "6" reference material that provide the baseline analytical results for comparison with reference samples; "7" replicate samples; and "9" sample taken from the environment (regular).
meth_cd: method code, the codes are documented in the "NWIS Method Code Dictionary"
result_cm_tx: comment about the water quality result
date_time: date and time the sample was collected. Missing values of time were substituted with “00:00” (12:00 midnight and start of day).
sample_cd: unique identifier for the water sample. The sample code is a concatenation of the date_time and site_no variables.
comments: comments pertaining to changes applied after the records were obtained from NWIS.
rep_pair_no: number used to identify replicate samples. Replicates are identified by matching a replicate sample (samp_type_cd eqaul to 7) with its corresponding environmental sample (samp_type_cd equal to 9).

Data obtained from the NWIS-QWDATA database on June 11, 2019 using the QWDATA system (U.S. Geological Survey, 2019).

U.S. Geological Survey, 2019, National Water Information System—Water-Quality System (QWDATA) data retrieval program.

site_no <- "433002113021701"  # well RWMC PROD
parm_cd <- "32102"            # carbon tetrachloride
xlim <- as.Date(c("1989-01-01", "2019-01-01"))
d <- samples[samples$site_no == site_no & samples$parm_cd == parm_cd,
             c("sample_dt", "result_va")]
ylab <- parameters[parameters$parm_cd == parm_cd, "parameter_nm"]
main <- sites@data[sites@data$site_no == site_no, "site_nm"]
inlmisc::PlotGraph(d, ylab = ylab, main = main, xlim = xlim,
                   type = "p", pch = 19, seq.date.by = "year",
                   center.date.labels = TRUE)
str(samples)