ASTM D – 96(). Standard Test Method for Determining Transmissivity and Storage. Coefficient of Low-Permeability Rocks by In Situ. ASTM D – 96(). Standard Test Method for Determining Transmissivity and Storage Coefficient of Low-Permeability Rocks by In Situ Measurements. AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM). Pumping Test. 1 . . D Test Method for Determining Transmissivity and. Storativity of.
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This chapter discusses the reasons, procedures and methods for water level measurements in the well and aquifer testing. It also summarizes what should be done with the discharge water from the testing process, keeping in mind potential contamination and other environmental concerns.
The requirements for the Wells Regulation on measuring and reporting water levels in test holes and dewatering wells are also provided. F4630 requirements listed in this chapter do not apply to shallow works, other exempted wells or the exempted activities discussed in Chapter 3: The person constructing a test hole or dewatering well is exempt from performing a yield test if the static water level is measured as described below. Before the structural stage of a test hole or dewatering well is complete, the person constructing the test hole or dewatering well must:.
D API Plain Form Hydrometer (Short Form)
The person constructing the well must record the static water level on the well record see Chapter Measuring the static water level or testing the well yield, in a test hole or dewatering well, is not required in any of the following situations:.
For further information as to who is required to perform the testing on a well or, if exempt, best management practices for retaining a person to perform the testing see Chapter 3: The above noted characteristics help determine if an aquifer can be used for a large taking or if interference will result from a large dewatering project.
Water levels measurements are important aspects and procedures of monitoring programs, pumping tests and hydraulic conductivity tests. The measurements are used in calculations to interpret the hydraulic characteristics of aquifers and wells. Measurements of static water levels from wells at a study site provide a current picture of groundwater flow gradients.
The information obtained from the tests help provide aquifer transmissivity, hydraulic conductivity, specific storage and specific yield. The information obtained from the testing also helps assess the long term sustained yield and efficiency of a well. There are four common types of pumping tests. Field hydraulic conductivity tests are designed field experiments to determine how groundwater is flowing through a formation.
This helps in the determination of groundwater flow velocity and other aquifer characteristics. There are five common types of field hydraulic conductivity tests. The discharged water from a test hole or dewatering well during pumping or purging must not cause an adverse effect to the natural environment or the impairment of any waters.
Steps need to be taken to ensure groundwater is appropriately discharged or collected and disposed of in an approved manner. For groundwater and well assessments, it is important to obtain accurate water levels, including static water levels, to determine groundwater flow directions, groundwater flow velocities, seasonal variations in water levels, hydraulic conductivity, and other hydraulic characteristics of wells and aquifers.
Documenting the static water levels for all test holes and dewatering wells at a site can provide information on the changing hydraulic conditions at the site. Analysis of this information will reveal changes in flow paths over time. This information is also essential to developing an understanding of the seasonal changes in water levels and associated variability of chemical concentrations at the site.
13.Water Level Measurements, Aquifer Testing & Discharge Water Handling
There are various types of methods and equipment to measure well water levels depending on the use of the water level data. The measurement methods are broken into the following two groups:.
The Wells Regulation – Before the structural stage of a test hole or dewatering well is complete, the person constructing the test hole or dewatering well must:. The Wells Regulation – Measuring of the static water level, or testing of the well yield, in a test hole or dewatering well is not required in any of the following situations:. Equipment Installation for further requirements and exemptions related to equipment installation.
While yield tests are not required for test holes or dewatering wells, there are several types of pumping tests used to determine aquifer and well hydraulic characteristics. Examples of pumping tests include constant rate and step-drawdown pumping tests. The standard also describes the conditions where each available method is applicable. To obtain accurate data, the pumping rate during the test should be accurately measured and recorded.
A Permit to Take Water under the Ontario Water Resources Act is required for many types of water takings including pumping a well for a yield test or an aquifer test that are greater than 50, L 11, Imp gal on any one day. Therefore, the person constructing the well should estimate the taking of water during the entire test before conducting the test. If the estimate shows the test will take more than 50, L on any one day, then the person constructing the well needs to obtain a Permit To Take Water from the Ministry prior to construction.
More information Permit to Take Water can be found on Ontario. When conducting a pumping test for a hydrogeological study in support of a category 3 Permit to Take Water application, it is important to follow the information found in the Technical Guidance Document for Hydrogeological Studies in Support of Category 3 Applications for Permit to Take Water Ontario Ministry of the Environment – Operations Division.
When conducting a pumping test for a hydrogeological study in support of a proposed private services residential subdivision, it is important to follow Procedure D, Technical Guideline for Private Wells: Hydraulic conductivity is a function of both the formation through which a fluid is moving and the fluid itself. Generally the finer the soil particle size the lower the hydraulic conductivity. Typically, both vertical and horizontal hydraulic conductivity are calculated.
Hydraulic conductivity helps determine the groundwater flow velocity at a study site. To determine field hydraulic conductivity, slug tests, bail tests, packer tests, pressure tests or tracer tests are performed on wells. A slug test consists of removing, adding or displacing a quantity of water in a well and monitoring the change in water levels with time.
A bail test is a slug test where water is removed from the well. The slug test method provides a measure of the horizontal hydraulic conductivity. Figure shows a cross-section of a well. A casing extends from above the ground surface into the subsurface.
The bottom of the casing is attached to a well screen. A rope extends from the ground surface into the well. A datalogger is shown to the right of the well on top of the ground surface. A cable extends from the datalogger into the well.
The bottom of the cable in the well is attached to a pressure transducer. A horizontal line is shown in the subsurface above the top of the slug. The horizontal line is the static water level SWL in the well. A horizontal line is shown above the SWL but below the ground surface. A horizontal line is shown in the subsurface above the top of the pressure transducer.
ASTM Standards November Update –
A horizontal line is shown below the SWL but above the pressure transducer. To the left of the well and above the ground surface, the diagram shows a bailer cylinder with a volume of water and a cable attached to the bailer. A packer test is typically used to test hydraulic conductivity in bedrock wells. An inflatable packer or packers are used to isolate a portion of the well.
Water is injected into the hole for a given length of time to test the area that has been sealed off by the packer s. Packer tests typically involve testing multiple zones in the well.
Two packer systems typically start testing at the bottom of a asstm and work upward. A single packer system typically tests a zone after astj a portion of the well. Further testing occurs with the single packer as the hole is drilled deeper. An increment of pressure is applied to the zone between the packers or below a single packer.
The rate of pressure decay is measured and analyzed using pressure gauges. A tracer test involves injecting a tracer material into the well and allowing it to move away from the well into the water bearing zone.
After a given period of time the well is pumped to recover the tracer. This is referred to as a single well tracer test. In other cases, nearby wells are used to detect the tracer moving through the water bearing zone. This is referred to as a multi-well tracer test. These tests are expensive and require a lot of experience in planning and interpretation. When using field methods to determine hydraulic conductivity, it is important to follow one or more of the following ASTM standards:.
The discharge water from a pumping test or other aquifer test must not cause an adverse effect to the natural environment and should not interfere with the test. To reduce the risks, it is important to consider the following:.
Discharge water from dewatering wells must not cause an adverse effect to the natural environment. Water from dewatering wells on contaminated sites e. V4630 other cases, permission or approval from a municipality is required to discharge the water into an approved sewer system. It is important for the person to determine if an environmental compliance approval is required before discharging d46300 water during a pumping or other aquifer test or as part of a dewatering project.
A guide to explain the sewage works process can be found on Ontario. Skip to main content.
Test holes and dewatering wells – Requirements and best management practices 2. Multi-level Monitoring Test Holes 9. Exemption – Yield Test The person constructing a test hole or dewatering well is exempt from performing a yield test if the static water level is measured as described below.
Measuring Static Water Level Before the structural stage of a test hole or dewatering well is complete, the person constructing the test hole or dewatering well must: Exemptions – Static Water Level Measuring Measuring the static water level or testing the well yield, in a test hole or dewatering well, is not required in any d46630 the following situations: Equipment A person who installs equipment in a well must ensure that the equipment is clean.
Best Management Practice — Measuring Well Discharges To obtain accurate data, the pumping rate during the test should be accurately measured and recorded.
Best Asfm Practice — Guidance on Pumping Tests for Residential Subdivisions When conducting a pumping test for asmt hydrogeological study in support of a proposed private services residential subdivision, it is important to follow Procedure D, Technical Guideline for Private Wells: Environment, Conservation and Parks. Ministry of the Environment, Conservation and Parks.
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