Wednesday, March 28, 2012

Dimock Well – HW-02 January 25, 2012 - a review of the data


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-02

With the exception of the following parameters, the remaining values were reported as NOT Detected (U) and duplicate (Z)

Total Coliform – Two samples  - (82 colonies per 100 ml and 1 colonies per 100 ml) – since EPA collected this sample at the end of the purging process – this suggests the well is vulnerable to near surface influence and the presence of total coliform would suggest the water is not potable.  This is a very common problem in NEPA and about 30 to 50% of private wells have total coliform bacteria.  The problem could be private well construction, type of well cap, or improper well siting.   The primary recommendation would be to inspect the well, shock disinfect the well, and retest.  If this was a regulated water source, it would be classified as not-potable, and disinfection would be required.  As stated, this is a common problem with private wells in PA and the significant variation in the two testing results could suggest induced contamination by the field samplers.  Retesting Recommended

Ethylene glycol –  the reported value is < 10 mg/L – there is no standard set by EPA or PA, but the EPA has a guidance limit of < 7 mg/L.  Other states have lower and higher standards:

New Jersey 0.300 mg/L (300 ppb)
Arizona 5.5 mg/L (5500 ppb)
New Hampshire 7.0 mg/L (7000 ppb)
Florida, Massachusetts, and Minnesota14.0 mg/L (14,000 ppb)
Minnesota

At a minimum, I would recommend retesting for ethylene glycol using a method that is more sensitive or conducting some type of standard additions analysis.

Chloride – 3.9 mg/L (OK) – drinking water standard is <  250 mg/L – this does not suggest any specific impact.

Sulfate – 8.9 mg/L (OK) – drinking water standard is <  250 mg/L – this does not suggest any specific impact.

Arsenic – 0.004 mg/L (Total) and 0.0026 mg/L (D) – drinking water standard is <  0.010 mg/L – this does not suggest any specific impact and arsenic is a common problem in NEPA – about 6 % of private wells have arsenic above 0.010 mg/L.  It would be advisable to monitor the arsenic level of the well on an annual basis. (OK)

Barium - 0.275mg/L (Total) and 0.263 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)

Boron – 0.050 mg/L (Total) and 0.0588 mg/L (D) – no specific drinking water standard drinking water standard is available. EPA appears to have a long-term health advisory of 2.0 mg/L, but other states have limits that range from 0.6 to 1 mg/L.   Therefore, this does not appear to suggest any form of impact.  (OK)

Calcium- 31.7 mg/L (Total) and 32.1 mg/L (D) – no specific drinking water standard drinking water standard is available.  (OK)

Copper – 0.0035 mg/L (Total) and 0.0025 mg/L (D)- Copper is regulated as a primary standard (EPA and PA) and secondary drinking water standard in Pennsylvania.  Primary standard 1.3 mg/L and secondary standard 1.0 mg/L.   (OK)

Iron – 1.62mg/L (Total) and 0.140 mg/L (D) – Iron is regulated as a secondary drinking water standard in Pennsylvania and the action limit is 0.3 mg/L.  Therefore, the total iron content exceeds the secondary drinking water standard.  Since the total value exceeds the limit and not the dissolved, this suggests that the primary recommendation would be to install a water treatment system to filter the iron colloids or particles from the water.  Because of the high bacterial issue, it is also possible that iron bacteria may be present in the water causing discolored and smelly water.  The water probably has a reddish or brown appearance. Elevated level of iron is a common water quality problem in Northeastern PennsylvaniaAction is Recommended, because of an aesthetic issue.
Lead – 0.0019 mg/L (Total) and 0.001 mg/L (D)- Lead is regulated as a primary standard (EPA and PA) at 0.015 mg/L, but the action level in PA for source water is 0.005 mg/L. Because of the hits for copper and lead, it is possible that the nuisance bacteria may be causing some corrosion related problems – Call MIC – Microbiologically Induced Corrosion – Problem recommend inspection of the well, camera survey, shock disinfection, and retesting.  This is a common problem in NEPA.  (Action Needed may be a warning sign of corrosion)

Magnesium- 5.73 mg/L (Total) and 5.75 mg/L (D) – no specific drinking water standard drinking water standard is available.  (OK)

Manganese– 0.112 mg/L (Total) and 0.105 mg/L (D) – Manganese is regulated as a secondary drinking water standard in Pennsylvania and the action limit is 0.05 mg/L.  Therefore, the total manganese content exceeds the secondary drinking water standard.  Since the manganese is in a dissolved form, the water could become browner in color over time.  Because the water coming out of the well has dissolved manganese, the water treatment system would require either chemical oxidation or some type of ion exchange system. Elevated level of manganese is a common water quality problem in Northeastern PennsylvaniaAction is Recommended, because of an aesthetic issue and it could be related to Iron-Related Bacteria and MIC.  (photos of iron bacteria on the website)

Sodium – 15.9 mg/L (Total) and 16.2 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 0.661mg/L (Total) and 0.677 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)

Thallium- < 0.001 mg/L (Total) and < 0.001 mg/L (D)  – Thallium is regulated as a primary drinking water standard by the EPA and PADEP in Pennsylvania and the action limit is 0.002 mg/L.  (OK)

Uranium 0.004 mg/L (Total) and 0.0039 mg/L (D)  – Uranium is regulated as a primary drinking water standard by the EPA and PADEP in Pennsylvania and the action limit is 0.030 mg/L.  (OK)

Zinc  < 0.002  mg/L (Total) and < 0.002 mg/L (D)  – Zinc is regulated as a secondary drinking water standard by the PADEP in Pennsylvania and the action limit is 5.0 mg/L.  (OK)

Ethane 0.57  mg/L  – No specific drinking water standard (OK)

Methane 18  mg/L  – No specific drinking water standard, but the level indicates supersaturated conditions.  This means the well pump is pulling in water that is not in equilibrium with the atmosphere.  The well 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 31 to 36.  Since a ratio of methane to ethane of over 1000 typically suggests a biogenic source and a value of under 100 suggests a thermogenic source, the available information would suggest a thermogenic source for the gas.  As a guide, it may be possible to use a ratio to suggest the source of the gas- “ if the ratio of methane to ethane is 25, the source is thermogenic, but if the ratio is over 2500, then it is biogenic" (Mr. Bob Pirkle, President of Microseeps, Inc.), but between 25 and 2500 this is where isotopic analysis is critical.  


No specific health concern, but a health risk associated with the potential for a flammable environment.  


Action needed to properly vent gas from the well, perhaps modifying the well, water treatment to reduce methane level in the water to < 7 mg/L or more,  and isotopic analysis recommended.

May be advisable to check the level of other gases, such as propane.

Total Dissolved Solids  95  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.  (OK)

Acenaphthylene – the reported level was  0.00001 mg/L. Acenaphtylene is a polycyclic aromatic hydrocarbon – PAHs are created when products like coal, oil, gas, and garbage are burned but the burning process is not complete. Acenaphthylene is a component of crude oil, coal tar and a product of combustion which may be produced and released to the environment during natural fires. Very little information is available on the document that was released and the report indicates that one sample had a detected at   0.00001 mg/L and the other sample was  non-detected.  There is no EPA or PADEP drinking water standard and the primary recommendation would be to retest the water. During retesting, it is critical to check for airborne sources of contamination during sampling.

“Note: PAHs have been detected in surface waters of the United States. In an assessment of STORET data covering the period 1980-82, Staples et al. (1985) reported median concentrations in ambient water of less than 0.010 mg/L for 15 PAHs (acenaphthene, acenaphthylene, anthracene, benz[a]anthracene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[g,h,i]perylene, benzo[a]pyrene, chrysene, fluoranthene, fluorene, indeno[1,2,3-c,d]pyrene, naphthalene, phenanthrene, and pyrene).

It appears that Arizona and Missouri recommended a limit of < 0.003 ug/L or <0.000003 mg/L.”

Retesting is Recommend -During retesting, it is critical to check for airborne sources of contamination during sampling and it would be advisable to attempt to use a method with a lower detection limit.  At this point, I am not sure if a certified method can detect acenaphthylene to the recommended level of 0.000003 mg/L – still researching.


Anthracene the reported level was  0.00023 mg/L (0.23 ug/L).  This  is an unregulated synthetic organic compound and polycyclic aromatic hydrocarbon.   PAHs are created when products like coal, oil, gas, and garbage are burned but the burning process is not complete. There is no EPA or PADEP drinking water standard and the primary recommendation would be to retest the water.

Retesting Recommended - During retesting, it is critical to check for airborne sources of contamination during sampling.  The EPA reports a trigger value of 1.3 mg/L, but I can not this reference.  I did find a reference to a DWEL of 2.0 mg/L.  It appears that the health-based screening requirement in California is 2.0 mg/L and a lifetime exposure limit is 10 mg/L- based on this information (OK).


Benzo(a)pyrene – the reported level was 0.00020 mg/L (0.00016 to 0.0002 mg/L).   The EPA and PADEP have a primary drinking water standard of 0.0002 mg/L.  The value is at the maximum contaminant level for a regulated water source.  The primary recommendation would be to continue to monitor this source and make sure to monitor the source following a recharge event.

4-Bromopheyl-Phenyl Ether – the reported level was 0.00018 mg/L – there does not appear to be a federal drinking water standard but Florida does appear to have an upper limit of 0.0010 mg/L.   (OK)

Butyl benzyl phthalate – the reported level was 0.00035 mg/L – “Benzylbutylphthalate, also called
n-butyl benzyl phthalate (BBP) or benzyl butyl phthalate, is a phthalate, an ester of phthalic acid, benzyl alcohol and n-butanol.”   The health based screening level appears to be 0.100 mg/L and the EPA Human Health Equivalent is 1.4 mg/L. Butyl benzylphthalate is an industrial solvent and additive used in adhesives, vinyl flooring, sealants, car-care products and some personal care products.  (OK)


Carbazole (Diphenylenimine)was reported at a level of 0.29 ug/L or 0.00029 mg/L. Carbazole is released to the atmosphere in emissions from waste incineration, tobacco smoke, aluminum manufacturing, and rubber, petroleum, coal, and wood combustion. If released to the atmosphere, vapor-phase carbazole is rapidly degraded by photochemically produced hydroxyl radicals (estimated half-life of 3 hr). In the particulate phase, the rate of degradation depends upon the adsorbing substrate.   The EPA does not have a regulated drinking water limit, but it appears Florida has set a standard of 0.0075 mg/L.   (OK)

Source: USEPA/Office of Water; Federal-State Toxicology and Risk Analysis Committee (FSTRAC).

4-chlorophenyl phenyl ether was reported at a level of 0.10 ug/L or 0.0001 mg/L.  The preliminary research suggests that this chemical has a relatively low solubility and would have a tendency to bind to soil and sediment.   In general, it is considered to be insoluble or have a low solubility in water.  The U.S. EPA Storet Data Base, 1,333 samples, 1.1% positive, median concentration less than 10 ug/L or 0.010 mg/L.  Because of the affinity to have only slight mobility in soil and water and because the well is vulnerable to near surface activity, it may be advisable to check the area around the well for evidence of surface contamination.

“4-Chlorophenyl phenyl ether which finds use as a dielectric fluid, can be released to the environment during its manufacture, formulation, and through its use in capacitors. If released to the atmosphere, 4-chlorophenyl phenyl ether should react with photochemically produced hydroxyl radicals with an estimated half-life of 1.3 days. Direct photolysis in the atmosphere should be an important fate process, as 4-chlorophenyl phenyl ether has an absorption greater than 290 nm. 4-Chlorophenyl phenyl ether should be expected to undergo biodegradation in soil and in water. 4-Chlorophenyl phenyl ether should display slight mobility in soil, and volatilization to the atmosphere may be an important process. If released to water, 4-chlorophenyl phenyl ether would be expected to adsorb to sediment and suspended material, can volatilize to the atmosphere, and should bioaccumulate in aquatic organisms. Degradation by direct photolysis in surface water has been estimated to proceed with a half-life of 200-400 days. Volatilization from water to the atmosphere should be an important fate process. The estimated volatilization half-life for a model river is 6 hours, while from a model pond which takes into account adsorption processes, the estimated half-life is 40 days. Exposure to 4-chlorophenyl phenyl ether should be by inhalation and dermal contact which might occur during its manufacture, formulation, or use in capacitors. 4-Chlorophenyl phenyl ether is an anthropogenic compound, and is not known to exist in nature.”   Florida appears to have established a standard of 0.010 ug/L.   Based on the available standard, the level seems appropriate, but it would be advisable to monitor the quality of the water and inspect the area for signs of surface contamination. (OK)

Dibenzofuran (Dixons) was reported at a level of 0.04 ug/L or 0.00004 mg/L. Dibenzofuran is used as an insecticide, to make other chemicals, and is a by-product of combustion. It is made from coal tar and has been found in coke dust, grate ash, fly ash, and flame soot.  In addition, it can be found in tobacco and as a combustion product, dibenzofuran may be released from the incomplete combustion of coal biomass, refuse, diesel fuel and residual oil, as well as from tobacco smoke.

Based on the available information, the primary recommendation would be to conduct a more detailed site-specific evaluation and conduct confirmation testing.  Since this well appears to be susceptible to near surface impacts, it may be possible to eliminate exposure by improving control at the wellhead to reduce vulnerability to contamination.  No clear standard, but follow-up testing and on-site evaluation is recommended.  Note: The aerobic decomposition in an aerobic and anaerobic environment is < 28 days to over 112 days.
Groundwater Chemicals Desk Reference by By John H. Montgomery (Google Books)

Note: Dibenzofuran was qualitatively identified in drinking water collected from Cincinnati,
Ohio in October 1978 and Philadelphia, Pennsylvania in February 1976. 

Retesting –should also include breakdown products.
Comment  = the presence of the partially combusted material and the bacterial contamination is making me believe there is a local source of contamination, i.e., old burn pit, burn barrels, etc.  This is not a judgment, but it makes me very interested in seeing this site and the condition of the well and surrounding area.

Lucas SV; GC/MS Analysis of Organics in Drinking Water Concentrates and Advanced Waste Treatment Concentrates: Vol 1. EPA-600/1-84-020a p. 45,147 (1984)

Fluoranthene (Benzo(j, k)fluorene) was reported at a level of 0.27 ug/L or 0.00027 mg/L and there is a trigger level reported at 0.63 mg/L.  It has been suggested that the EPA has set for total PAHs of 0.2 ug/L or 0.0002 mg/L and I can not find an EPA reference that confirms this statement, but Florida has a health advisory level  of 0.5 ug/L or 0.0005 mg/L for benzo(k)fluorene

Note: “Polycyclic aromatic hydrocarbons are a group of chemicals that occur naturally in coal, crude oil, and gasoline. PAHs are also present in products made from fossil fuels, such as coal-tar pitch, creosote, and asphalt.  Fluoranthene adsorbs strongly to soil and would be expected to remain in the upper layers of soil. However, it has been detected in groundwater samples which demonstrates that it can be transported there by some process(es). It slowly degrades in soil (half-life ca 5 mo to 2 yr).”  Based on the reported trigger level and the standard used for Florida, this value does not appear to violate a trigger level, but monitoring is advisable. http://www.doh.state.fl.us/environment/community/health-advisory/HAL_list.pdf

Benzo(k)fluoranthene was reported at 0.32 ug/L or 0.00032 mg/L and the reported EPA trigger level is 0.029 mg/L.    Florida has a health advisory at 0.0005 mg/L. (OK)  Still researching

Benzo(b)fluoranthene was reported at 0.15 ug/L or 0.00015 mg/L and the reported EPA trigger level is 0.0056 mg/L. Florida has a health advisory at 0.0005 mg/L.  (OK) Still researching

Fluorene was reported at 0.10 ug/L or 0.0001 mg/L and the reported EPA trigger level is 0.220 mg/L, but has a DWEL of 1.00 mg/L.  Florida  has a health advisory at 0.500 mg/L. (OK)
Still researching- “Fluorene is a polycyclic aromatic hydrocarbon (PAH) released from the incomplete combustion of fuels including oil, gasoline, coal and wood, as well as waste materials; it is an intermediate in production of dyes and other chemicals”- The reported health based standard was 0.3 mg/L or 300 ug/L.
http://www.ewg.org/tap-water/chemical-contaminants?file=contaminant&contamcode=2264

Hexachlorobenzene (HCB) - was reported at 0.22 ug/L or 0.00022 mg/L and the reported PADEP/ EPA has a MCL of 0.001 mg/L. (OK)  Florida also has a standard of 0.001 mg/L.  (OK)

Ortho Nitroaniline (2-Nitroaniline)- the reported value was 0.00007 mg/L and the EPA indicates a “Trigger Level” of 0.15 mg/L.  The NY Regulations suggest a limit of 0.005 mg/L is the principle organic standard. (OK)

3-Nitroaniline -the reported value was 0.00012 mg/L and the EPA indicates that there is no “Trigger Level”.  The NY Regulations suggest a limit of 0.005 mg/L is the principle organic standard. (OK)
http://www.bnl.gov/gpg/files/Annual_Reports/2001pdf/Table1-03.PDF

4- Nitrobenzenamine - the reported value was 0.00014 mg/L and the EPA indicates that there is a “Trigger Level” at 0.061 mg/L.  The NY Regulations suggest a limit of 0.005 mg/L is the principle organic standard. (OK)

4-Nitrophenol - the reported value was 0.00017 mg/L and the EPA indicates that there is no “Trigger Level”.  The NY Regulations suggest a limit of 0.001 mg/L is the standard for the total amount of phenolic compounds. (OK)

n-Nitrosodimethylamine  (NDMA) - the reported value was < 0.005 mg/L and the EPA indicates that there is  “Trigger Level” at 0.00004 mg/L.     It appears this could be a by-product of chlorination.  NDMA can be produced and released from industrial sources through chemical reactions, such as those that involve alkylamines with nitrogen oxides, nitrous acid, or nitrite salts. Potential industrial sources include byproducts from tanneries, pesticide and rocket fuel manufacturing plants, rubber and tire manufacturers, alkylamine manufacture and use sites, fish processing facilities, foundries, and  dye manufacturers (ATSDR 1989).  In 2011, Health Canada established a drinking water guideline at a maximum acceptable concentration (MAC) of 0.00004 mg/L, based on an assessment by the Federal-Provincial-Territorial Committee on Drinking Water (CDW). EPA has a 10-4 Cancer Risk of 0.00007 mg/L.
Therefore, the primary recommendation would be to resample and use a method with a lower detection limit.   

Note: 10-4 Cancer Risk: The concentration of a chemical in drinking water corresponding to an excess estimated lifetime cancer risk of 1 in 10,000.

n-Nitrosodiphenylamine-- the reported value was 0.00017 mg/L and the EPA indicates that there is a “Trigger Level” at 1.0 mg/L. 

It dissolves in water, but it binds to soil and does not move quickly through soil. It breaks down in air, water, and soil within several weeks. For drinking water, the EPA has suggested trigger limits that range from 0.070 to 0.70 mg/L.
http://www.epa.gov/iris/subst/0178.htm  Looks Ok – but may want to monitor.

Pentachlorophenol – the reported value was <  0.005 mg/L, but the EPA/ PADEP MCL is < 0.001 mg/L.   The NY Regulations suggest a limit of 0.001 mg/L is the standard for the total amount of phenolic compounds. The EPA has a DWEL of 0.2 mg/L.
 Looks OK, but retesting using a method with a lower detection limit may be advisable.

benzo(ghi)perylene– the reported value was <  0.0021 mg/L, but the there is no MCL or trigger limit.  Like most PAHs, benzo(g,h,i)perylene is used to make dyes, plastics, pesticides, explosives and drugs. It has also been used to make bile acids, cholesterol and steroids. It has been suggested that the EPA has set for total PAHs of 0.2 ug/L or 0.0002 mg/L and I can not find an EPA reference that confirms this statement, but Florida has a health advisory level of 0.210 mg/L for benzo(ghi)perylene
(OK)

phenanthrene– the reported value was <  0.0023 mg/L, but the there is no MCL or trigger limit. Florida has a health advisory level of 0.210 mg/L for phenanthrene
(OK)

dimethyl phthalate – the reported value was 0.00015 mg/L and the reported trigger limit is 1.4 mg/L. Florida has a health advisory level of 70 mg/L for dimethyl phthalate. 
(OK)

di-n-octyl phthalate (DNOP)- the reported value was 0.00028 mg/L and no trigger limit is reported. Exposure to di-n-octylphthalate occurs mainly from eating food or drinking water that is stored in plastic containers.http://www.atsdr.cdc.gov/tfacts95.html    There does not appear to be an action limit, but it would be advisable to monitor and conduct a site-specific survey. “This type of plastic can be used for medical tubing and blood storage bags, wire and cables, carpetback coating, floor tile, and adhesives. It is also used in cosmetics and pesticides.”

Pryene - the reported value was 0.00026 mg/L and the reported trigger limit is 0.087 mg/L. Florida has a health advisory level of 0.210 mg/L for Pryene.  (OK)

indeno(1,2,3-cd)-pryene- the reported value was 0.00021 mg/L and the reported trigger limit is 0.003 mg/L. It is a polycyclic aromatic hydrocarbon (PAH).  (Source for standard not available). (OK)

This sample seems to have as series of detects for polycyclic aromatic hydrocarbons (PAHs), plus is positive for bacterial contamination.

 “Polycyclic aromatic hydrocarbons (PAHs) are a group of over 100 different chemicals that are formed during the incomplete burning of coal, oil and gas, garbage, or other organic substances like tobacco or charbroiled meat. PAHs are usually found as a mixture containing two or more of these compounds, such as soot. “

Again – I have not been to the site, but I am just wondering if the because the well is vulnerable to bacterial contamination is it also vulnerable to air-borne or local contamination related to the burning of materials.   I have recommended the following:
a. an evaluation of the well – including a shock disinfection.
b. local wellhead survey to attempt to identify local sources of potential contamination.
c. Recommended retesting for a number of parameters to either monitor or to use a different method with a lower detection limit.  This should include monitoring following a recharge event.
d. Methane above the action limit – recommend venting and other modifications to the well and regular monitoring. http://www.water-research.net/methanegas.htm  The gas appears to have a thermogenic origin, but additional analysis is recommended.
e. Retesting for glycol using a more sensitive method.
f. Iron and manganese exceeds secondary drinking water limits that were set for aesthetic reasons.
Again – this is not about cause and effect- it is an honest review of the data.  (Period)


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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5 comments:

  1. Sorry this is a long and very detailed review - where possible I have provided links to critical documents.

    ReplyDelete
  2. Excellent content Brian. Thanks for the analysis and compiling all the links.

    ReplyDelete
  3. We are happy to see the fact based information is being used.

    ReplyDelete
  4. We are happy to see the fact based information is being used.

    ReplyDelete
  5. More resources for private well owners - http://www.water-research.net

    ReplyDelete