National Groundwater Awareness Week: 10 Facts About Groundwater and Testing

From March 7-13, 2021 we celebrate National Groundwater Awareness Week to advocate for the protection and safety of groundwater. Water is one of the most precious natural resources. Read more to learn why!

#1 Approximately 164 million rely on groundwater for drinking water

In America, about half of the population (approximately 164 million) relies on groundwater for drinking water, from both private and public sources. This accounts for 26% of all fresh water used for all purposes in the US, the remainder being used for irrigation, industrial cooling, etc.

#2 Irrigation is the biggest user in the US

Groundwater helps feed the world; irrigation is the biggest user in the US, with about 53 billion gallons consumed daily.

#3 Nitrates, metals, volatile and semi-volatile organic compounds, and pesticides

The most common pollutants found in groundwater are nitrates, metals, volatile and semi-volatile organic compounds, and pesticides.

#4 Private well water should be tested a minimum of once per year

Private well water should be tested a minimum of once per year. Drinking water supplies obtained from shallow wells and surface water sources should be tested more frequently (i.e. seasonally), as they are more vulnerable to contamination. The USEPA does not regulate private drinking water wells, and testing requirements for those may vary by state and locality. According to the USGS, more than 43 million people rely on private wells as their source of drinking water!

#5 EPA Issued the Ground Water Rule (GWR) in 2006

EPA issued the Ground Water Rule (GWR) in 2006 to improve drinking water quality and provide protection from disease-causing microorganisms. It applies to public water systems that use groundwater as a source of drinking water.

#6 Ground Water Rule basic requirements

The basic requirements of the Ground Water Rule include:

  • Sanitary surveys
  • Source water monitoring
  • Compliance monitoring
  • Corrective actions

#7 Phase II Environmental Site Assessment

Groundwater and soil testing are often performed as part of a Phase II Environmental Site Assessment.

#8 Common sources of groundwater contamination

Common sources of groundwater contamination are leaking above and underground storage tanks, septic systems, uncontrolled hazardous waste disposal, landfills, chemical and road salts, and atmospheric contaminant deposition that enter surface water and stormwater runoff.

#9 In situ and ex situ groundwater remediation

If your groundwater is contaminated, there are two types of groundwater remediation:

  • In situ (in-place): contaminated water is treated underground within the groundwater zone without having to remove the groundwater for aboveground treatment.
  • Ex situ (off-site): contaminated water is removed from the ground and treated aboveground either on- or off-site.

#10 Treatment methodologies

Groundwater can be treated in numerous ways, including in situ methodologies with as injection technologies (e.g., chemical oxidation, air sparging) or ex-situ methods such as pump and treat that may incorporate air stripping, filtration/adsorption, and/or thermal systems. Complex treatment sites may employ a combination of these approaches.

Apex Associated Press (Apex AP) represents contributions from various authors within the Apex professional community.


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