In addition to human health, the economy and society can be impacted by groundwater quality. Contamination of groundwater can have a negative impact on economic development, community image, property values, and our collective quality of life. Groundwater is the only affordable water source available in many regions of the nation, and clean water at a fair price is crucial. Cleaning up contaminated groundwater is typically very expensive and time-consuming. Cleaning up even minor contamination sites frequently costs thousands of dollars.

Contaminants can occur in well water due to agricultural activity, septic system use, household chemical use/ disposal, age of the plumbing or industrial activity. The frequency of groundwater testing and the contaminants to test for depend on factors such as the potential sources of pollution and the type of well. Another consideration is ensuring that the private well complies with proper well construction standards.

The only way to detect most pollutants is by testing

A water’s taste, smell, or color is not necessarily an indicator of water quality. Many of the most hazardous contaminants are undetectable to the senses. According to American Petroleum Institute guidelines (API-HF1), a baseline assessment program that involves sampling neighboring water wells should be carried out before hydraulic fracturing activities start in a new location. After hydraulic fracturing, fresh water wells should also be sampled. As part of their regulatory program, at least one state (Colorado) mandates that certain water wells in different parts of the state be sampled.

In the event of a contamination complaint, regulations in another state (Pennsylvania) presume that any oil and gas company must prove that they have not contributed to deterioration of the quality of groundwater used for drinking water purposes in the vicinity of oil and gas wells.

EPA certified laboratory for sampling containers and instructions

Proper protocols may include:

using appropriate containers and seals
purging of the well prior to sample capture
collection at points before water treatment equipment
following sample container filling procedures
following storage and holding time requirements
utilizing appropriate analysis methods; and
following appropriate quality control/ quality assurance protocols
Sampling should be conducted by someone familiar with sampling procedures. Analyses should be conducted by an accredited laboratory using appropriate analysis methods. You may be able to obtain a list of qualified laboratories by contacting your local Health Department, State Water Quality Agency shown on the Regulations By State page or County Extension Agent.

It is important for the landowner to have an oil and gas operational sampling and analysis of their groundwater conducted by a professional for constituents that may provide a reasonable baseline for post fracturing analysis. The following is a good basic list of constituents that should be considered for analysis prior to oil & gas operations.

Major cations and anions

pH
Specific Conductance
Total Dissolved Solids
Benzene, Toluene, Ethyl benzene, Xylene (BTEX)/ Diesel Range Organics (DRO)/ Gasoline Range Organics (GRO)
Total Petroleum Hydrocarbons or Oil & Grease (HEM)
Arsenic
Barium
Calcium
Chromium
Iron
Magnesium
Selenium
Boron
Sodium
Chloride
Potassium
Bicarbonate
Dissolved Methane

Once hydraulic fracturing has taken place and a record of the actual chemicals used is available, it would be advisable to consider having a sampling and analysis conducted on the groundwater for the chemicals shown on the record that match those listed above or those that are by-products, reaction products or daughter products of those listed above. This is important because many of the chemicals used in hydraulic fracturing will be degraded, oxidized, or otherwise modified during the fracturing process.

Thus, simply looking for the chemicals on the list shown above may not yield enough information for a comparative analysis. However, to minimize costs for the landowner, an alternative analysis should be conducted for at least TDS and Dissolved Methane. An increase in the concentration of either of these constituents could indicate that further, more complete sampling and analysis should be conducted.

Conductivity

Conductivity is a measure of the ability of water to pass an electrical current. Because dissolved salts and other inorganic chemicals conduct electrical current, conductivity increases as salinity increases. Organic compounds like oil do not conduct electrical current very well and therefore have a low conductivity when in water. Conductivity is also affected by temperature: the warmer the water, the higher the conductivity.

Why it is important to evaluate?

Conductivity is useful as a general measure of water quality. Each water body tends to have a relatively constant range of conductivity that, once established, can be used as a baseline for comparison with regular conductivity measurements. Significant changes in conductivity could then be an indicator that a discharge or some other source of pollution has entered the aquatic resource.
Significant changes (usually increases) in conductivity may indicate that a discharge or some other source of disturbance has decreased the relative condition or health of the water body and its associated biota. Generally, human disturbance tends to increase the amount of dissolved solids entering waters which results in increased conductivity. Water bodies with elevated conductivity may have other impaired or altered indicators as well.

Parameters to be analyzed

pH15:

pH of solution is taken as –ive logarithm of H2 ions for

many practical practices. Value range of pH from 7 t0 14 is

alkaline, from 0 to 7 is acidic and 7 is neutral. Mainly drinking

water pH lies from 4.4 to 8.5. The pH scale commonly ranges

from 0 to 14.

Turbidity15:

Suspension of particles in water interfering with

passage of light is called turbidity. Turbidity is caused by wide

variety of Suspended particles. Turbidity can be measured either

by its effect on the transmission of light which is termed as

Turbiditymetry or by its effect on the scattering of light which is

termed as Nephelometry. As per IS: 10500-2012 the acceptable

and permissible limits are 1 and 5 NTU respectively.

T.D.S15:

Difference of total solids and suspended solids is used

to determine the filterable solids by the help of filtrate and

following the procedure as above. In water sample it can also be

estimated from conductivity measurement. The acceptable and

permissible limits As per IS: 10500-2012 is 500 and 2000 mg/l

respectively.

Total hardness16:

As per IS: 10500-2012 Desirable limit and

Permissible limit for hardness is lies between 200 to 600 mg/l

respectively. The effect of hardness is Scale in utensils and hot

water system in boilers etc. soap scum’s Sources are Dissolved

calcium and magnesium from soil and aquifer minerals

containing limestone or dolomite. The Treatment of hard Water

is Softener Ion Exchanger and Reverse Osmosis process. The

degree of hardness of drinking water has been classified in

terms of the equivalent CaCO3 concentration as follows: Soft –

0-60mg/l, Medium – 60-120 mg/l, Hard – 120-180 mg/l, Very

hard – >180 mg/l.

Sulphate:

Natural water contains sulphate ions and most of

these ions are also soluble in water. Many sulphate ions are

produce by oxidation process of their ores, they also present in

industrial wastes. The method to measure quantity of sulphate is

by UV Spectrophotometer. As per IS: 10500-2012 Desirable

limit for Sulphate is 200 and 400 mg/l in Permissible limit

Nitrate:

Nitrate is present in raw water and mainly it is a form

of N2 compound (of its oxidizing state). Nitrate is produced

from chemical and fertilizer factories, matters of animals,

decline vegetables, domestic and industrial discharge. The

method to measure quantity of nitrate is by UV

Spectrophotometer. As per IS: 10500-2012 Desirable limit for

nitrate is max.45 and no relaxation in permissible limit.

Conclusion

Ground water testing is crucial when dealing with uncertain water quality, as is the case with many groundwater sources. This can help determine the necessity for groundwater tests and treatment options. Doing some testing beforehand is always preferable to having to go back and test after the equipment has been installed and isn’t working properly when dealing with the unknown. As crucial as any other test that may be conducted is a physical examination of the water, so be sure to record any color, taste, or odor that you notice. Customers are most worried about these attributes.

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