Current through Register Vol. 43, No. 52, December 26, 2024
(a) The
groundwater monitoring program shall include consistent sampling and analysis
procedures to ensure that monitoring results provide data representative of
groundwater quality in the zone being monitored.
(b) The owner or operator shall develop a
sampling and analysis plan to submit to the department for approval that
includes the following:
(1) a quality
assurance and quality control program for field sampling procedures and
laboratory analysis that provides:
(A)
quantitative detection limits;
(B)
the degree of error for analysis of each chemical constituent;
(C) equipment decontamination procedures; and
(D) other field quality assurance
protocols;
(2) a sample
preservation and shipment procedure that maintains the integrity of the sample
collected for analysis;
(3) a
chain of custody procedure to prevent tampering and contamination of the
collected samples prior to completion of analysis;
(4) the sampling procedures and analytical
methods that will be used, why they are appropriate for groundwater sampling
and whether they accurately measure constituents in groundwater samples; and
(5) the statistical method or
methods listed in subsection (h) of this regulation which will be used in
evaluating monitoring data for each constituent detected.
(c) Groundwater samples shall not be
fieldfiltered prior to laboratory analysis. The director may require field
filtered samples in cases where turbidity affects the validity of the results.
(d) The owner or operator shall
determine the rate and direction of groundwater flow each time groundwater is
sampled. Groundwater elevations in wells that monitor the same waste-management
area shall be measured within a period of time short enough to avoid temporal
variations in groundwater flow that could preclude accurate determination of
groundwater flow rate and direction.
(e) The owner or operator shall conduct
quarterly groundwater monitoring for one year to determine background
concentrations for each of the monitoring parameters or constituents required
in the detection groundwater monitoring program, set out in K.A.R.
28-29-113(a).
(f) Background
groundwater quality may be established at wells that are not located
hydraulically upgradient from the MSWLF unit if:
(1) hydrogeologic conditions do not allow the
owner or operator to determine what wells are hydraulically upgradient; or
(2) sampling at other wells will
provide an indication of background groundwater quality that is as
representative or more representative than that provided by the upgradient
wells.
(g) The number
of samples collected shall be consistent with the appropriate statistical
procedures determined pursuant to this regulation.
(h) The following methods shall be acceptable
statistical methods to be utilized in evaluating groundwater monitoring data,
and shall be applied separately to each constituent detected in each well:
(1) a parametric analysis of variance (ANOVA)
followed by multiple comparisons procedures to identify statistically
significant evidence of contamination. This method shall include an estimation
and testing of the contrasts between each compliance well's mean and the
background mean levels for each constituent;
(2) an analysis of variance (ANOVA) based on
ranks followed by multiple comparisons procedures to identify statistically
significant evidence of contamination. This method shall include an estimation
and testing of the contrasts between each compliance well's median and the
background median levels for each constituent;
(3) a tolerance or prediction interval
procedure in which an interval for each constituent is established from the
distribution of the background data, and the level of each constituent in each
compliance well is compared to the upper tolerance or prediction limit;
(4) a control chart approach that
gives control limits for each constituent; or
(5) another statistical test method that
meets the following performance standards:
(A) The statistical method used to evaluate
groundwater monitoring data shall be appropriate for the distribution of
chemical parameters or hazardous constituents. If the distribution of the
chemical parameters or hazardous constituents is shown by the owner or operator
to be inappropriate for a normal theory test, then the data may be transformed
or a distribution-free theory test may be used. If the distributions for the
constituents differ, more than one statistical method may be needed.
(B) If an individual well comparison
procedure is used to compare an individual compliance well constituent
concentration with background constituent concentrations or a groundwater
protection standard, the test shall be done at a type I error level no less
than 0.01 for each testing period. If a multiple comparisons procedure is used,
the type I experiment-wise error rate for each testing period shall be no less
than 0.05; however, the type I error of no less than 0.01 for individual well
comparisons must be maintained. This performance standard shall not apply to
tolerance intervals, prediction intervals, or control charts.
(C) If a control chart approach is used to
evaluate groundwater monitoring data, the specific type of control chart and
its associated parameter values shall be protective of human health and the
environment. The parameters shall be determined after considering the number of
samples in the background data base, the data distribution, and the range of
the concentration values for each constituent of concern.
(D) If a tolerance interval or a prediction
interval is used to evaluate groundwater monitoring data, the levels of
confidence and, for tolerance intervals, the percentage of the population that
the interval shall contain, shall be protective of human health and the
environment. These parameters shall be determined after considering the number
of samples in the background data base, the data distribution, and the range of
the concentration values for each constituent of concern.
(E) The statistical method shall account for
data below the limit of detection with one or more statistical procedures that
are protective of human health and the environment. Any practical quantitation
limit (pql) that is used in the statistical method shall be the lowest
concentration level that can be reliably achieved within specified limits of
precision and accuracy during routine laboratory operating conditions that are
available to the facility.
(F) If
necessary, the statistical method shall include procedures to control or
correct for seasonal and spatial variability as well as temporal correlation in
the data.
(i) Any owner or operator wishing to use an
alternative statistical test shall seek the approval of the department and
provide a justification for the alternative test. The justification shall
demonstrate that the alternative method meets the performance standards listed
in paragraph (h)(5) above.
(j) The
owner or operator shall determine whether or not there is a statistically
significant increase over background values for each parameter or constituent
required in the particular groundwater monitoring program that applies to the
MSWLF unit.
(1) The owner or operator shall
submit the statistical analyses to the department within 45 days of receipt of
analytical results.
(2) If
requested by the department, the results of the statistical analyses shall be
provided in electronic form via computer disc or other electronic means.
(3) If requested by the
department, the raw analytical data shall also be provided.
(k) In determining whether a
statistically significant increase has occurred, the owner or operator shall
compare the groundwater quality of each parameter or constituent at each
downgradient monitoring well to the background value of that constituent,
according to the statistical procedures and performance standards specified in
this regulation.
