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Well and Septic Care Guide

The Web Hunterdon

George F. Wagner, Chief of Staff/Director of Public Safety
Karen B. DeMarco, Department Head/County Health Officer


314 State Route 12
County Complex, Building #1
Flemington, NJ 08822-2900

Hunterdon County Department of Health

Environmental Health Services



Houseowners Guide

Well and Septic System Care
Hunterdon County

A Homeowner's Guide
Hunterdon County Department of Health
Route 12 County Complex, Building #7
PO Box 2900
Flemington, NJ 08822-2900
908-788-1351 * health@co.hunterdon.nj.us
Water: One of the Wonders of the World
Well Water
Water Flow from the Aquifer
Clean Water Has Its Own Problems
Additional Testing
The Private Septic System
How Does A Septic System Work
Septic System Design
Preventing Septic System Problems From Inside Your Home
Preventing Septic System Problems From Outside Your Home
Useful Community Resources
Hazardous Waste Clean-Up Day


One of the Wonders of the World

Not interstellar space travel; not the Pyramids; no, not even the Grand Canyon. One of the greatest wonders of our world today is clean, plentiful, potable (drinkable) water. Stop and consider how often you use water during a 24-hour period. Consider the importance of clean water coming out of your tap. Could you manage your household if your water system became polluted?

Could you manage your household without a clean, safe water supply?This information was designed specifically for Hunterdon County homeowners, and it stresses the importance of properly maintaining individual well and septic systems. As you read through, consider this: Materials put down the drain now may very well come out of the faucet in the months ahead.

Despite the proximity of the Delaware River, the South Branch of the Raritan River, and New Jersey’s two largest reservoirs, Hunterdon residents rely primarily on ground water for household water supplies. In contrast, New Jerseyans in other parts of the state depend upon surface water resources. In Hunterdon, most residents use private wells as a water source and on-site septic systems for sewage disposal. This booklet is designed to help homeowners understand how these systems operate, and how to keep them operating smoothly. This information should help provide long-term protection for one of our most precious resources.

Our most valuable resource... A clean, available water supply
Drilled Well Graphic

New Jersey well codes require that all drilled wells be cased with a minimum of 50 feet of steel pipe and be constructed with a minimum of 20 feet of casing set into ‘unweathered’ rock (bedrock). The casing is installed in sections, with each joint carefully sealed. This design, along with final grouting (use of pressure grouted with cement) prevents surface seepage and contamination. Area wells drilled after 1978 should have a well head that is exposed 12 inches above ground level to reduce the chances of surface water carrying pollutants into the well.


Well Water

The high quality of area water is due to uncontaminated aquifers (underground, water-bearing rock) and is free of chlorine that is present in treated, urban water supplies.

As the sketch below indicates, private wells carry a certain vulnerability. Their risk comes from how the land surface is being used – or abused. The closer a well is to a source of groundwater contamination, the higher the risk of contaminated water. While water companies are required by law to test customers’ water regularly, owners of private wells are ‘on their own’.

Sources of groundwater contamination

Hunterdon County has a very complex geology, with a wide variety of soil types. Most of the aquifers consist of fractured rock formations. There is a great range of well depths throughout the county, ranging from a minimum of 50 feet to more than one-thousand feet, depending on the geographic area.


Water Flow from the Aquifer

When a resident turns on the tap, the well pump is activated and water is drawn out of the fractured rocks and into the well. The pumped withdrawal of water creates a ‘cone of depression’. In other words, water in all contiguous layers of rock is drawn towards the well. When the tap is turned off, the water returns to its static level.

As water is drawn from the aquifer, it will be replaced by normal rainfall or, indirectly, from underground movement of water out of nearby streams and reservoirs. Ground water moves very slowly, only a few inches per year in many areas. It is easy to see that once its contaminated, an aquifer is slow to cleanse itself. In fact, it is almost impossible to cleanse, even when using available man-made technology.


Clean Water Has Its Own Problems

Natural elements in your water can be removed with treatment equipment.Given the variety of rock and soil types in Hunterdon County, it follows that there would be some variation in the natural chemistry of its drinking water, Most water in the area is rather ‘hard’, which produces calcium deposits. The ‘lime’ deposits (actually calcium carbonate) can be removed by soaking your kettle, humidifier, etc. overnight with white vinegar (rinse it well before re-using).

Two other naturally occurring elements common in local drinking water are iron and manganese. They are not harmful to our health, but at higher concentrations can cause staining of plumbing fixtures, dishes and laundry.

treating and neutralizing water below 6.5 on pH scaleA common complaint about local water is acidity. Water that measures below 6.5 pH is considered excessively acidic. In the northern part of the county (north of Route 78) acidic water is common and neutralizing equipment is often required to prevent the corrosion of plumbing. When acid is present and corrosion occurs, it is easily identified by blue-green staining where copper plumbing exists. Acid-produced corrosion can also leach dangerous heavy metals, such as lead, from soldered joints.

Other undesirable natural elements that our in our water supply include sulfur, barium and copper – each of these are associated with odd geological formations. These elements do not ordinarily present a human health concern, but rather one of aesthetics – affecting the taste, color or smell of the water.

Radon gas has also been found dissolved in well water in Hunterdon County – sometimes at levels high enough to cause special concern. Very high levels must be present in water to cause elevated air levels in the home. The primary source of unsafe radon levels is gas migration into homes through basement entry points. Control efforts, therefore, should focus on these areas rather than on well water as a source. (For more information about radon gas, contact the Department of Health.)

New Jersey’s Department of Environmental Protection recommends that residents using private wells have them tested twice a year to be sure the well is free from harmful bacteria.

The Hunterdon County Department of Health and/or the South Branch Watershed Association can assist homeowners in locating a suitable lab. Regular testing is a very wise precaution, and can reveal important trends in the quality of your water.


Additional Testing

If a home is located near a gas station, industrial facility, old dump site, accidental spill site or where past land use has been questionable, water may require more extensive testing. The following three tests may be in order:

Basic water analysis for new home includes testing for bacteria, acidity, nitrate, iron and manganese

Volatile Organic Scan (VOS) - looks for common industrial pollutants such as degreasers, solvents, etc.
Petroleum Hydrocarbon Testing– looks for oil and gasoline
Heavy Metal Testing– lead, cadmium and other heavy identifies metals

While these tests are expensive and not recommended for most households, they can be important to residents living adjacent to the sites mentioned above. Call the Hunterdon County Department of Health if you need more guidance regarding these water tests. Remember: Shallow wells and springs are extremely vulnerable to pollution and should be tested frequently. Replacement of these systems may be needed and in the long run, makes good economic sense.


The Private Septic System

Properly designed, installed and maintained spetic systems impose little adverse effect on the environmentOver 80% of Hunterdon County homeowners rely exclusively on private septic systems to properly treat and dispose of domestic waste.

Lack of federal funding for sewer plant construction, as well as the economic impact of attempting to sewer large, sprawling rural townships, will make the use of individual septic systems the primary source of waste water disposal for a long time to come. In addition, septic systems treat effluent adequately and return it to the aquifers to be used and reused.


How Does A Septic System Work?

A septic system has two key components:

The Septic Tank: A container usually prefabricated from concrete. It receives waste water from your bathroom, kitchen and laundry room. Heavy particles settle at the bottom as sludge and light materials float to the surface of the tank forming a scum. Bacteria in the system help to break down and liquefy the organic matter which is carried to the disposal field as effluent.

A septic tank should be sized to allow enough time for settling and floatation of effluent Septic Systems must be installed according to state law or local ordinancescomponents. The partially-treated effluent can then flow from the septic tank to the sub-surface disposal area.

The Disposal Field: This consists of a distribution box and perforated distribution lines (laterals) installed below the ground in gravel beds or trenches where further treatment filtering action takes place. Seepage pits can also be used in some places.

Septic systems must be designed and installed to meet standards established by state law, and in some instances, local ordinances.


Septic System Design

Septic System DesignSeptic Systems must be designed and installed to meet standards established by state law and, in some instances, local ordinances. These laws require testing of the soil to determine its permeability. Various tests can be conducted, including tube permameter, percolation test, basin flooding or pit-bailing.

When designing a system, an engineer checks the level of the water table to ensure that it is the required distance below the bottom of the subsurface disposal area. If it is not, groundwater contamination may result. This disposal area must also be sized to handle the daily waste water from your home.

Caution: Gases generated within the septic tank can accumulate to toxic concentrations which have been fatal to humans. No person should ever enter a septic tank or even just peer into the tank through a manhole cover without exercise extreme caution.


Preventing Septic System Problems From Inside Your Home

  1. Proper care and maintenance of your septic system helps ensure its proper functioning and longevityCut back on household usage – fix leaky faucets and toilets, and don’t flush the toilet unnecessarily. Install low-flow fixtures for showerheads, toilets, etc.
  2. Limit the amount of cleaning agents that you use. They can be harmful to a septic system if used in excess.
  3. Space your showers, laundry and dishwasher loads, allowing your system to ‘rest’ between high-volume uses.
  4. Never allow toxic and hazardous chemicals to be disposed of through your septic system. This includes paint thinner, surplus paint, oil, gasoline or grease. These items should be saved and disposed of at the Hazardous Waste Days sponsored by the Hunterdon County Solid Waste Department.
  5. Limit paper products to the absolute minimum and use white toilet paper to avoid product dyes. Also, avoid putting coffee grounds, disposable diapers, sanitary napkins, tampons and cat litter through your septic system.
  6. Resist the use of garbage disposals – they place a heavy burden on your system.
  7. Avoid using septic system cleaner additives. They are not necessary, and some can interfere with the natural bacterial action of your system.
  8. Have your septic system pumped every three years to clean out the accumulated sludge. Pumping extends the life and efficiency of your system. All solids should be removed as part of this pumping procedure.
  9. Prior to any septic system modifications (including repairs, alterations or new installations), a permit is required by the County Department of Health.


Preventing Septic System Problems From Outside Your Home

  1. Be sure to have your septic tank pumped out at least once every 3 yearsKnow exactly where your septic system is located – before you have trouble. If you can’t locate it, ask a neighbor, the previous owner or your builder to help you find it. You can also check the records at the Department of Health. If no design records are available, the Department will refer you to other professional resources.
  2. There should be no visible effluent, nor any odor, associated with the system. These warning signs indicate a problem may exist.
  3. Direct roof drains and sump pumps discharges away from your disposal field. Septic systems do not work well if you overload the drainage field.
  4. Do not physically abuse your disposal field by parking vehicles or placing permanent structures (such as above ground pools or decks) over the area. Check with the county Health Department for proper setback distances.
  5. Keep large trees from growing on or close to the disposal area. This will prevent tree roots from clogging the distribution laterals.
  6. When you have your system pumped, the Health Department recommends you install a concrete riser and cover that is level with the ground. This will make checking and pumping the system much easier in the future.


Useful Community Resources

Your tax dollars are at work providing you with many resources for assistance with well and septic problems.

Hunterdon County Department of Health
Route 12 County Complex Flemington
E-Mail: health@co.hunterdon.nj.us
Hunterdon County Solid Waste and Recycling
1 East Main Street Flemington
NJ Department of Environmental Protection 609-292-3131
South Branch Watershed Association
A non-profit environmental organization which sponsors well-testing programs for private homeowners
Echo Hill Park, Clinton Township
Hunterdon County Soil Conservation District
Provides information on county soil types, erosion control, storm water management
Hunterdon County Extension Service
Provides useful information for home, yard and farm care
Water Testing See ‘Laboratories – Testing’ in Yellow Pages
Waste Oil Disposal
Gas and service stations displaying the recycling logo are required to accept waste oil. Also, waste oil can be recycled at the County's Hazardous Waste Clean-Up programs.


Hazardous Waste Clean-Up Day

Waste such as those listed below should never be disposed of in a septic system, but rather safely set aside and brought to the next Hunterdon County Hazardous Waste Clean-Up Day.

* Paint thinner * Weed killers
* Solvent-based paints * Oven cleaner
* Spot remover * Ammonia
* Pesticides * Waste oil
* Film development chemicals

Watch the local papers for the next date, visit the Hazardous Waste Cleanup Day Webpage, or contact the Hunterdon County Division of Solid Waste and Recycling office at 908-788-1110.


The Hunterdon County Department of Health would like to thank the South Branch Watershed Association for their assistance in the preparation of this important document. And, to acknowledge the funding support received from the New Jersey Department of Environmental Protection, which made the entire project possible.


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