06-096DEPARTMENT OF ENVIRONMENTAL PROTECTION
(iii)purge stabilization criteria. Sample collection at the same flow rate used to purge the well may occur when the following stabilization criteria are met:
a.specific conductance, dissolved oxygen and turbidity stabilize within 10% of the reading range for 3 consecutive readings;
b.pH is within 0.1 standard unit; and
c.water level is stabilized.
(c)Order of Sampling. An order for the sampling of monitoring wells must be included in a monitoring program which uses non-dedicated equipment; any changes in the sampling order must be approved by the Department.
(i)the order in which monitoring wells in the program will be sampled must consider the likelihood for contamination in each well in the respective well network. Wells at locations least likely to be found contaminated must be sampled first.
(ii)the order in which samples will be collected from each monitoring well must remain consistent over time and must be based on the parameter’s volatility. The United States Environmental Protection Agency (US EPA) provides the following guidelines on order of sample collection:
a.Volatile Organic Compounds (VOCs)
b.Total Organic Carbon (TOC)
c.Total Organic Halogens (TOX)
d.any samples approved by the Department for field filtration
e.samples for field parameter measurement (usually Temperature, Dissolved Gases, Alkalinity and Specific Conductance)
f.large-volume samples for Extractable Organic Compounds
g.samples for Total Metals
h.samples for Nutrient Anion Determinations
(d)Except as otherwise approved by the Department based on site-specific characteristics, all samples must be whole and unfiltered and must be collected in a manner which produces the least possible sampling-induced turbidity.
(e)Field Analyses. All field test equipment must be calibrated at the beginning of each sampling day and checked and re-calibrated according to the manufacturer's specifications. Calibration data must be reported with the analytical results.
(f)Quality Assurance/Quality Control.
Chapter 405: Water Quality Monitoring, Leachate Monitoring, and Waste Characterization
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