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Ground Water

Ground Water

Ground Water

Looking for an answer. We installed a new well about a year ago. the local state health office district engineer (DE) is suspicious it is GWUDI. He has no hard eveidence to support his claim. The well is greater than the minimum distance of 50' from any surface water body. It's design meets all state and county requirements. The seal is set @ 63' the minimum depth is 50'. the bore hole is 20' into ignious rock. We measured pH, conductivity and temp. of the well and the nearby pond. No correlation. The DE is requiring us to add turbidity monitoring to our proposed Fe/Mn treatment plant and test the well water for coliform monthly for a year. Also perform MPA test before and after a significant rain (1") for one year. He has imposed an MCL of .3NTU. What arguments can anyone suggest that would force him to modify his opinion.

RE: Ground Water

what does the local code require?   

RE: Ground Water

Local code requires the following as I mentioned in my question: Minimum distance from a surface water body 50'. Minimum depth of seal 50'
For a water system <1000 service connections the MCL for turbidity is .5NTU.

RE: Ground Water

Is DE acting on the requirements of the Contract's Special Provisions?

RE: Ground Water

The igneous rock may be the tricky one especially if it is fractured it could present a direct hydraulic connection to the pond. Too bad you haven't been get water quality tests done for the last year and you could perhaps prove to the DE that there is no problem.

Consider yourself lucky with the 50 feet requirement, another state requires the following:

The source must be within 500 feet of a surface water source (year round or intermittent/seasonal) and meet one of the following hydrogeologic setting criteria
as determined by the Source Water Assessment or other Department approved hydrogeologic study;
· 500 feet within a fractured bedrock or layered volcanic aquifer;
· 200 feet within a coarse sand, gravel and boulder aquifer;
· 100 feet within a sand and gravel aquifer;
· 75 feet within a sand aquifer

RE: Ground Water

seems reasonable to me.  While the construction details are to code, bedrock aquifers are prone to surface water interaction.  Taking turbidity measurements and monthly MPA (with extras for heavy rains) doesn't strike me as too bad.  In Virginia if it's a public water supply well and you have a PWSID, the state lab does the testing for you.


¡papá gordo ain't no madre flaca!

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