Water sampling may be required in many situations for general information or compliance with federal, state and local statutes. Water sampling may be required for water well quality, groundwater contamination, storm water run-off and NPDES compliance.
Water Well Sampling
Water may appear clear and pure, but water from wells or other sources may contain dissolved minerals and other substances. Generally, ground water provides a good supply of safe water, that doesn’t need much treatment. If you are a private well owner, you need to test your water supply to insure the well provides safe, high quality water.
With the advice of your county Health Department or Cooperative Extension office, a decision can be made on what tests are needed for your water supply. After selecting the tests, samples will be taken in the prescribed method and submitted for analysis a a qualified, accredited lab.
Steps required for taking a water sample will vary for different tests. Timeliness and cleanliness are important when collecting any water sample. Using certified, sterile collection bottles and not your own bottles to take a sample is essential to accurate results.
A water sample needs to be submitted to the lab within 48 hours (sometimes sooner) of collection. In some cases, it must be kept cold prior to testing. Care must be taken to prevent anything but the water from contacting the inside of the bottle or the cap. Contaminants are often present in small amounts. Careless sampling prevents accurate test results.
Storm Water Sampling
Most industrial stormwater permits require installation and implementation of control measures to minimize or eliminate pollutants in stormwater runoff from your facility. The control measures you choose for your facility must be documented in your facility‐specific Stormwater Pollution Prevention Plan (SWPPP). The results of your stormwater monitoring will help you determine the effectiveness of your control measures, and overall stormwater management program. Evaluation of your stormwater management program will include inspections, visual assessments, and monitoring (i.e., sampling) of specified stormwater discharges. Regular stormwater inspections and visual assessments provide qualitative information on whether there are unaddressed potential pollutant sources at your site, and whether existing control measures are effective or need to be reevaluated. Stormwater sampling provides quantitative (i.e., numeric) data to determine pollutant concentrations in runoff and, in turn, the degree to which your control measures are effectively minimizing contact between stormwater and pollutant sources, and the success of your stormwater control approach in meeting applicable discharge requirements or effluent limits.
The following are the types of industrial stormwater monitoring requirements typically included in industrial general permits:
Visual Assessments of Discharges: Permittees are required to regularly and frequently (e.g., quarterly under the 2008 MSGP) take a grab sample during a rain event and assess key visual indicators of stormwater pollution – color, odor, clarity, floating solids, settled solids, suspended solids, foam, oil sheen, and other qualitative markers of pollution. The findings of these assessments are used to trigger further facility inspections and corrective actions to modify problems found at the site.
Indicator or Benchmark Sampling: Stormwater samples are collected from a site’s discharge points (or outfalls) for laboratory analysis and the results are compared with benchmark pollutant concentrations as an indicator of the performance of stormwater control measures. A benchmark pollutant concentration is a level above which a stormwater discharge could adversely affect receiving water quality (and control measures must be evaluated) and, if below, the facility is not expected to have an impact on receiving water quality. This type of monitoring differs from “compliance monitoring” (see below) in that exceedances of the indicator or benchmark levels are not considered violations, but rather “red flags” that could point to a problem at the site with exposed pollutant sources or control measures that are not working correctly. For instance, the 2008 MSGP includes “benchmarks” that are based to a large degree on EPA’s aquatic life criteria. Where the average of samples taken over four consecutive quarters exceed the applicable benchmark concentration of a particular pollutant, the permittee is required to investigate whether the higher pollutant levels can be attributed to some pollutant source or faulty control measure(s), and to address such problems through corrective action and possibly further monitoring.
Compliance Sampling: Where a facility is subject to one of the Federal effluent limitation guidelines (ELGs) addressing limits on stormwater runoff, sampling is required to determine compliance with those limits.
Monitoring Requirements for Discharges to Impaired Waters: General industrial permits may have special monitoring requirements for facilities that discharge pollutants of concern into impaired waters.
Ground Water Sampling
Ground-water monitoring is a complex undertaking. Cost-effective monitoring relies on careful planning and critical reading of the scientific literature. These activities will ensure that the application of well placement, construction, sampling, and analytical procedures results in the collection of high quality data. The information needs of each program must be recognized and all subsequent monitoring network design and operation decisions must be made in light of the available data. In this sense, monitoring is an evolutionary process which should be refined as the information base expands.
Routine monitoring efforts may be sustained for decades. Therefore, as the data base for a specific situation is developed, it is unreasonable to follow preliminary guidelines offered for generalized monitoring activities. High quality hydrologic and chemical data collected in the detection phase of monitoring are essential in planning future activities. Effective monitoring efforts are both dynamic and flexible. Our present understanding of natural and contaminated subsurface conditions is developing, but incomplete. The practical elements of a viable long-term ground-water monitoring effort include:
- Evaluation of hydrogeologic setting and program information needs,
- Proper well placement and construction,
- Evaluation of well-performance and purging strategies,
- Execution of effective sampling protocols which include the appropriate selection of sampling mechanisms and materials, as well as sample collection and handling procedures.
Proven ground-water monitoring procedures are in a state of rapid development at the present time. It is prudent to specify monitoring methods and results which will permit the collection of high quality, representative information for the most sensitive chemical constituents of interest. All methods used in a specific situation should be carefully documented so that one can learn as the information needs and dimensions of the monitoring effort mature.
Volatile organic compounds and redox- or pH-sensitive chemical constituents place significant demands on monitoring efforts. It is clear that, given properly constructed and maintained sampling points, sampling and handling methods which minimize sample disturbance are the most cost effective means available to provide high quality ground-water information. Positive displacement, no-gas-contact sampling mechanisms constructed of appropriate inert materials (Teflon®> stainless steel > other plastics or ferrous materials in the order of inertness) provide the basis for an effective monitoring effort.
Actual sampling and analytical performance (accuracy, precision, detection and quantitation limits) which ensures the collection of water originating from the formation of interest should be established in every monitoring effort, regardless of the specific information needs of individual programs. This can best be assured by the implementation of quality assurance and quality control measures which are checked and documented carefully. The current state of our understanding of effective monitoring procedures requires that common sense also play a large part in planning ground-water sampling efforts.
Mantis Environmental can service all of your water sampling needs. Professional timely and experienced personnel will custom tailor the sampling to your specific needs.