Comment
1. Without predrilling data, it is not possible to comment
on the cause for any water quality problems.
2. Where possible, I have noted situations where elevated
levels of a water quality parameter exists in Pennsylvania .
3. If duplicate analysis provided, I attempted to use the
highest reported value.
5. This is not about cause and effect; it is about a review
of the data.
Well – HW-1
With the exception of the following parameters, the
remaining values were reported as NOT Detected (U)
Anionic Surfactants
– < 0.01 mg/L – the secondary drinking water standard for foaming agents is
0.5 mg/L. (OK)
Ethane –0.350 mg/L – No specific drinking water standard (OK)
Methane – 12.0 mg/L – No specific
drinking water standard. (OK).
The
well water is above the new action limit of 7 mg/L and methane gas mitigation
measures should be employed. These
measures not only include venting the well, but also potentially modifying the
well, installing treatment, or taking other action. For more details, go to http://www.water-research.net/methanegas.htm
There
are places in PA were baseline levels of methane gas are at or above 7 mg/L. In
general, I would estimate that 1 to 3 % of private wells may have elevated
levels of methane. In addition to
modifying the well, it would be advisable to conduct isotopic analysis. Based on the ratio of methane to ethane, the ratio
is 34. This suggests the gas is of thermogenic origin and isotopic analysis is
critical. No specific health concern – but action needed
to properly vent gas and it may be necessary to modify the well and isotopic
analysis recommended.
May be advisable to check the level of
other gases, such as propane.
Methane/Ethane Ratio: 34 (Thermogenic)
Ethylene glycol – the reported value is < 10 mg/L – there is
no standard, but the EPA has a guidance limit of < 7 mg/L. Other states have lower and higher standards:
At a minimum, I would recommend retesting for ethylene
glycol other other glycol compounds using a method that is more sensitive or
conducting some type of standard additions analysis.
Chloride – 4.36
mg/L (OK) – drinking water standard is < 250 mg/L – this does not suggest any specific
impact.
Sulfate – 5.49 mg/L (OK) – drinking water standard is < 250 mg/L – this does not suggest any specific impact.
Barium - 0.304 mg/L (Total) and 0.316 mg/L (D) – drinking water standard is < 2 mg/L – this does not suggest any specific impact and barium is typically detectable in non-saline impacted water at a level of less than 1 mg/L. (OK)
Calcium- 7.89
mg/L (Total) and 8.21 mg/L (D) – no specific drinking water standard drinking
water standard is available. (OK)
Magnesium- 3.64
mg/L (Total) and 3.76 mg/L (D) – no specific drinking water standard drinking
water standard is available. (OK)
Manganese– 0.0022
mg/L (Total) and 0.0019 mg/L (D) –
Manganese is regulated as a secondary drinking water standard in Pennsylvania and the
action limit is 0.05 mg/L. (OK)
Sodium –18.1 mg/L (Total) and 19.1 mg/L
(D) – – no specific drinking water standard drinking water standard is
available, but the EPA has added it to the Candidate List to provide more
analysis. The EPA’s initial value of 20
mg/L has been clearly identified as not realistic. When chloride (salt is sodium chloride) is
present at a concentration of over 250 mg/L, the water can have an “off” taste.
At 400+ mg/L chloride, the water will taste definitely salty. (Source- Dr.
Brian Redmond, Professional Geologist). (OK)
Strontium – 0.655 mg/L (Total) and 0.694 mg/L (D) – no specific drinking water standard
drinking water standard is available, but it is on the EPA Candidate List. The EPA recommends that drinking
water levels of nonradioactive strontium should not be more than 4 mg/L. The report limit is consistent with
background levels in Northeastern Pennsylvania . If the background level was above 4 mg/L, it
would be advisable to test for radiological parameters, especially
alpha/beta. (OK)
Total Dissolved Solids –
< 16 mg/L – Total Dissolved Solids is regulated as a
secondary drinking water standard by the PADEP in Pennsylvania and the action limit is 500
mg/L. (Question – this value seems inaccurate or a typo – This should be
redone.)
No major problems
1. Heterotrophic bacteria data is not provided.
2. Methane/Ethane Ratio could suggest the source of the
methane is Thermogenic and the level of methane is above the action level of 7 mg/L.
Go to: http://www.water-research.net/methanegas.htm
3.Total Dissolved Solids results seem inaccurate or there is a typo in the draft report.
3.Total Dissolved Solids results seem inaccurate or there is a typo in the draft report.
4. Retesting for glycols using a more sensitive technique is
recommended.
Document can not be
copied in whole or part without the expressed written permission of Mr. Brian
Oram, B.F. Environmental Consultants Inc. http://www.bfenvironmental.com
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