NC State Extension Publications


Skip to Introduction

Lawns are ecosystems that impact surface and groundwater systems. The grasses found in lawns clean the environment by absorbing gaseous pollutants and intercepting pesticides, fertilizers, dust, and sediment. Irrigation water properly applied to lawns remains on site to recharge water supplies. In addition, grasses release oxygen and reduce glare, noise, and summer temperatures.

The need to protect surface and groundwater quality is a serious environmental issue. Good design can prevent or minimize erosion and runoff. Good design provides for buffers and natural vegetated areas near streams, wetlands, and other fragile areas. It also minimizes the development of gullies, the redirection of streams, and the unnecessary disruption of the natural landscape, especially around drainage ditches, and stream banks.

Proper management practices need to be developed and followed to protect this environment. The purpose of this publication is to provide you with management strategies to preserve and protect water resources.

Best Management Practices (BMPs)

Skip to Best Management Practices (BMPs)

Every lawn maintenance decision you make in managing a turf area will have an effect on the ecosystem of the site. Best Management Practices, or BMPs, are a series of cultural practices designed to maximize resources while minimizing risk to the environment. BMPs cover important aspects of turf management from the original design of the area to its daily maintenance. This publication provides a discussion of some of the BMPs applicable to the creation, protection, and maintenance of a turfgrass ecosystem.

Turfgrass Selection

Turfgrass selection can have a large impact on water quality. Using planting material that is free of objectionable weed and crop content can minimize weed problems and the need for herbicides. Adapted, improved grasses require less inputs of fertilizer, pesticides, and water. Healthy plants are better able to cope with pests and recover from pest injury or environmental stress.

Grasses differ in performance and cultural requirements across regions and locations. Base your selection on existing environmental conditions (soil pH, soil type, level moisture, degree of sunlight, topography), the purpose for which the area is to be used, and expected management intensity. Check with a county Extension Center for an updated list of grasses that perform best in your area or refer to Extension publication, Carolina Lawns, AG-69.


Skip to Fertilizers

The primary objective of a fertility program is to create an environment where nutrients are available to sustain healthy plant growth with minimal risk to water quality. Since nutrients are not always found in adequate supply in the soil, many turfgrasses require regular fertilization to meet the needs of the plant.

Improper fertilization practices can pose a risk to groundwater quality. The lawn care manager must have a working knowledge of how the plant uses nutrients and the fate of nutrients in the soil. With this information, you can implement a fertility program that will benefit the turf and minimize risks to water sources.

Nitrogen and Phosphorous

Skip to Nitrogen and Phosphorous

Nitrogen and phosphorus are the nutrients most likely to affect water quality. A management plan is critical to maintain the lawn and the environment.

Phosphorus is important in the establishment and rooting of plants. However, through erosion and sedimentation, phosphorus can cause undesirable algal blooms and abnormal growth of aquatic plants in lakes and ponds.

Nitrogen is required for good plant growth and is often associated with the green color in plants. Excess nitrogen may cause an increase in the occurrence of disease, thatch accumulation, decreased tolerance to environmental stress, reduced wear tolerance, restricted root systems, and decreased potential for recuperation from environmental stress or pest attacks.

Nitrogen Carriers

Skip to Nitrogen Carriers

The form of nitrogen applied in fertilizer can affect the degree of runoff or leaching. Nitrate (NO3) has the highest potential to leach or runoff into water sources. Runoff can occur if the nitrogen is applied to frozen ground, to steep slopes, at high rates, or before an excessive rainfall or irrigation. Leaching is likely if the soil is saturated through intense irrigation, has insufficient organic matter and is sandy. Other forms of nitrogen are less likely to be changed to NO3 if the soil is fine- textured or if organic matter is present.

The carrier of nitrogen, the form in which it is supplied to the soil, plays an important role in the potential for losses to ground and surface waters. Table 1 belowoutlines the characteristics of many of the nitrogen carriers available on the market today. Generally, nitrogen sources are separated into quickly-available and slowly-available categories.

Quickly-available forms provide a rapid response by the plant by releasing large quantities of nitrogen into the soil. Inorganic salts, such as ammonium sulfate dissolve rapidly in the soil water providing large amounts of plant-available nitrogen in a short period of time. Urea is a quickly-available, organic nitrogen source and is commonly applied in a liquid or granular form. Once entering the soil, several reactions take place rapidly to convert the urea to the plant-available nitrate form. However, there is a high potential foliage burn and leaching potential under some environmental conditions.

Slowly-available products such as IBDU or urea-formaldehyde rely on chemical and/or microbial activity for release of plant-available nitrogen. Some of the urea-formaldehyde products are available as solutions or suspensions and can be applied in liquid form. Coated urea products such as sulfur coated urea and polymer coated urea rely on the coating to control the release of plant-available nitrogen into the soil solution.

Natural organic sources are composed of materials such as processed municipal sewage sludge, composted plant or animal debris, and various other organic wastes. Plant-available nitrogen is released from these products through chemical and microbial activity in the soil. As a result, temperature and moisture are important factors governing microbial action and the release of plant-available nitrogen. Warm moist conditions favor high levels of microbial activity, and the release of nitrogen can be accelerated.

Overall, slowly-available nitrogen sources provide a more controlled release of nitrogen with longer residuals and are less likely to be lost to groundwater through leaching than quickly-available products.

Table 1. Characteristics of nitrogen carriers.
Fertilizer Source N % Content Leaching Potential Burn Potential Low Temperature Response Residual Effect
Quickly Available
Ammonium Nitrate 33-34 High High Rapid Short
Calcium Nitrate 16 High High Moderate Short
Ammonium Sulfate 21 Moderate High Rapid Short
Urea 45+46 Moderate High Rapid Short
Slowly Available
Slowly Soluble
IBDU 31 Moderately Low Low Moderate Moderate
Ureaformaldehyde 38 Low Low Very Low Moderate to Long
Slow Release
Sulfur Coated Urea 22-38 Low Low Moderate Moderate
Polymer Coated Urea 10-20 Low Low Low Moderate
Natural Organics
Sewage Sludge 6 Very Low Very Low Very Low Long
Other Natural Products 3-10 Very Low Very Low Very Low Long

Fertilizer Management BMPs

Skip to Fertilizer Management BMPs

Base fertilizer applications on a soil test. A soil test will show the types and levels of nutrients in the soil. Most newly planted areas should be tested during the construction phase and every one to two years after that, depending on the type of turf being grown.

  • Wait a minimum of three to four weeks after the last fertilization before sampling.
  • Be careful to submit a sample for analysis that is truly representative of the area.
  • Make sure the equipment used to take the sample is clean and free of contaminants. Clean equipment between samples.
  • Sample to a uniform depth—preferably to 3 or 4 inches.
  • Take 15 to 20 soil cores from each area being tested, using a one inch diameter soil probe and thoroughly mix them in a plastic container or paper bag. Do not use a metal bucket which may affect results.
  • It may take several weeks before you receive the results of your test, so plan to submit your samples far enough in advance.
  • Submit samples to a reputable laboratory for testing and interpretation. The North Carolina Department of Agriculture & Consumer Services provides soil testing. Submit samples to the Agronomic Division--NCDA&CS, 4300 Reedy Creek Road, Raleigh, NC 27607, or to the N.C. Cooperative Extension office in your county.

Supplement the soil test with a plant tissue analysis. A plant tissue analysis is a diagnostic tool that can be used by a lawn care manager to identify potential nutrient problems. The analysis measures the concentrations of different nutrients in the tissue and indicates adequacy or deficiency. For more information contact your N.C. Cooperative Extension center.

Core or aerify compacted soil. Coring and aerification at the time of fertilization can aid the fertilizer getting into the soil. This is especially important for phosphorus. Coring compacted, sloped areas will reduce runoff.

Minimize fertilizer rates on slopes. The application of high rates of nitrogen and phosphorus fertilizer on slopes near surface water increases the risk for negatively impacting water quality. Use no more than 0.25 to 0.50 pounds of nitrogen per 1,000 square foot per application.

Do not apply fertilizers directly into lakes, drainage areas and other bodies of water. Maintain a buffer zone of low- maintenance gasses or natural vegetation between areas of highly maintained turf and water. This prevents erosion and produces a trap or filter for unwanted nutrients.

Consider using iron as a supplement to nitrogen for greening response. Iron can be used alone or in combination with nitrogen to provide a greening response. Reduced nitrogen applications will minimize possible nitrate leaching into groundwater. Rates will vary with grass type and environmental conditions. Follow label directions.

Use a slowly-available carrier on sandy soils. Sandy soils put groundwater at greater risk of contamination. Slowly- available nitrogen fertilizers are less likely to be leached below the root zone than quickly-available sources on highly leachable soil.

If you use quick-release nitrogen on sandy soils with little organic matter, or near shallow water tables, use no more than 0.25 to 0.50 pounds nitrogen per 1,000 square foot per application. Plant response is often better under a program of lower levels of nitrogen with more frequent applications.

Time applications carefully. Quickly-available sources should not be applied before a heavy rainfall or irrigation. Nitrogen has the highest chance of leaching under cool and wet weather. Cold temperatures (55 to 60 degrees Fahrenheit) slow microbes and plant uptake, as well as loss through volatilization and denitrification.

Irrigate after each application of quick release fertilizer. Irrigation of 0.25 to 0.50 inches of water moves the fertilizer off the foliage and into the ground where it can be used by the plants. It decreases loss by runoff and volatilization and minimizes the risk of foliar burn.

Irrigate to replace water that is used up. Provide only enough water to compensate for that lost by evapotranspiration. Over-irrigation will produce water movement beyond the rootzone, increasing the potential for leaching.

Recycle grass clippings (grasssycling). When practical, clippings should be allowed to remain on the lawn to decompose and recycle nutrients back into the turf. If clippings are removed, they should not be blown into ditches, streams, lakes, or placed in areas such as ditches or concrete areas where they have a high probability of running off into surface water sources.

Use a drop (gravity) spreader near bodies of water or impenetrable areas. Centrifugal (rotary) spreaders should not be used near bodies of water because of the potential of granules entering the water.


Skip to Irrigation

Determining the appropriate level of irrigation for an area of turfgrass is vital to the health of the plant and the preservation of water quality. Underirrigating produces wilt and dessication. Overirrigating increases the potential for leaching and surface runoff and weakens the turf, making it more prone to pest attacks and environmental stress.

A properly designed and installed irrigation system will apply a uniform level of water at the desired rate and time. The amount and frequency of irrigation should be based on the needs of the grass, soil conditions, and expected weather conditions. Water to just below the existing root zone to encourage further rooting. Deeper watering does not benefit the plant and, as mentioned above, may leach contaminants into the groundwater.

Temperature, wind, relative humidity, and soil moisture are all factors that determine the use of water by the plant.

In those situations where homeowners are responsible for irrigation, the following BMPs would be helpful in protecting water quality.

Irrigation BMPs (for home owners)

  • Water to a depth just below the root system. If you observe runoff, shut the system off and wait for the existing water to enter the soil. Go back and rewet until the water reaches the appropriate depth.
  • Do not irrigate again until you see visual signs of wilt or footprinting. A soil probe can aid in the visual estimate of moisture content.
  • Sloped areas, compacted soils, and sandy soils will need to be irrigated in short, frequent intervals.
  • Water in the early morning for best results. If you must water in the evening, allow sufficient time for the leaves to dry before nightfall to lessen the chance of disease. Avoid midafternoon watering to reduce loss from evaporation.
  • Don't be alarmed at brown, withered leaves as a result of drought. These are normal signs of dormancy on cool season grasses. Lawns allowed to go dormant should be watered every three weeks in the absence of rainfall to prevent injury to grasses due to heat and drying.
  • Do not plan to water a surface before it is used by heavy traffic. Heavy traffic on a wet soil leads to compaction, which may lead to runoff.
  • Periodically test the irrigation system to make sure it is producing an acceptable level of uniformity.

Maintaining the appropriate grass height encourages deeper roots, reduces the potential encroachment of weeds and cools the surface of the grass. Thatch is a layer of partially decomposed organic matter situated above the soil surface. This layer can be effective in capturing and breaking down pesticides, but it can also be damaging when it is too thick (12 inch) and creates a favorable environment for insects and plant pathogens. The thickness can be reduced by vertical mowing, coring, and topdressing.

If homeowners are responsible for mowing, pass along the following guidelines.

Mowing BMPs

  • Use the highest acceptable mowing height for the grasses being grown. See Table 2.
  • Never remove more than 33 percent of the leaf surface at one time. When prolonged rains make it impossible to mow regularly, raise the mower for the initial cutting and gradually lower the mower to the proper height.
  • Do not mow when grass is excessively wet to avoid compacting and clumping of clippings.
  • Leave grass clippings on the lawn. This is referred to as grasssycling. Every 100 pounds of dried grass clippings contains 4 pounds of nitrogen, 12 pound of phosphorus, and 2 pounds of potassium. Grassycling may enable you to reduce your fertilization requirements by 25 percent.
  • Compost grass clippings if you cannot leave them on the turf. Composted grass clippings, well as other yard waste, can be used as a mulch or soil conditioner. The Extension publication, Composting: A Guide to Managing Organic Yard Wastes, AG-467, provides good information about composting yard materials.

Table 2. Guidelines for mowing heights.

Lawngrass Height after Mowing (inches)
Bermudagrass 34 to 112
Zoysiagrass 34 to 112
Centipedegrass 1 to 112
Kentucky bluegrass, fine fescue, or perennial ryegrass 112 to 212
Tall fescue 212 to 312

Integrated Pest Management (IPM) Program

Skip to Integrated Pest Management (IPM) Program

An Integrated Pest Management (IPM) program is a management system that uses all available methods to keep pests at acceptable levels while minimizing the effect on people, the environment, and turf. Pesticides are only one of several options available to you. Other options include genetic, regulatory, physical, biological, and cultural solutions. A reduced reliance on pesticides is an important factor in managing sites for water quality. A sound IPM program will include:

  • A Knowledgeable Manager
    Knowledge is the cornerstone to any successful IPM program. Be aware of the grasses being grown, the pests likely to be a problem, and the conditions that may impact pests and the grasses being maintained.
  • A Written Plan
    This plan should include objectives for each section of the lawn and the degree of acceptable injury from pests. This will help define pest threshold levels. Specific management practices to include non-chemical control measures should be included. They will vary with each section of the site.
  • Defining Pest Threshold Levels
    Determine what is acceptable for each site, such as whether weeds should be allowed in low maintenance settings or how many insects can to tolerated per square foot. Some threshold levels have been reported for certain insects.
  • Implementing Appropriate Cultural Practices
    Use of agronomically sound cultural practices results in a healthy, dense vigorous turf that is better able to ward off pests and pest injury.
  • Monitoring Pest Activity
    Most pests are easiest to manage when they are immature and few in number. Frequent scouting can help determine when pest activity or injury is in its initial stages.
  • Maintaining Accurate Records
    Keeping accurate and up-to-date records of pest activity, actions taken and the results of those actions will assist you in future planning and may limit you in legal liability cases.

Pesticide Selection and Use

Skip to Pesticide Selection and Use

Although pesticides are sometimes necessary to keep pests at tolerable levels. Sole reliance on chemical control can no longer be justified. Rising chemical costs, increased resistance to pesticides, and environmental concerns as well as the potential for leaching or runoff discourage their exclusive use.

Some of the criteria that should be used in selecting a pesticide include the pest to be controlled, the turfgrass species the pest is infesting, the season and growth stage of the pest, the level of control desired, the application method required for the pesticide, the duration of control from the pesticide, and the possibility of environmental contamination from pesticides. For effective management, you should take into consideration all of the above factors.

Because of the problem of plants, insects, and diseases becoming pesticide-resistant, it is important that the manager frequently rotate pesticides with different modes of action for the target organism.

After all of the factors mentioned above are considered and the options are narrowed, you should look at the pesticide leaching potential rating (PLP). See Tables 3, 4, and 5. A pesticide with a low rating would be very unlikely to move into groundwater or surface waters. A pesticide with a high rating may be easily transported offsite, quickly leach into groundwater, or may persist long enough to allow it to enter or surface groundwaters even though it moves very slowly.

The PLP values given in the following tables are based on the soil retention, persistence, rate of application, and percent pesticide reaching the ground. You should be aware that the PLP rating may change from site to site depending on microbial decomposition, soil pH, soil type, photodecomposition (degradation from sunlight), or transformation of chemical properties due to exposure to light, volatilization (changing of solids and liquids into gasses), and water volumes applied after pesticide application.

Finally, you should also keep in mind that leaching is only one of many considerations in selecting a pesticide. There will be some instances where a pesticide exhibits low leaching potential but because of its high potential toxicity to wildlife, such as fish, extra precautions may be necessary around water. These precautions should be mentioned on the label.

Pesticides currently available for use on agricultural, turfgrass, horticultural, and residential pests in North Carolina have been thoroughly tested by the pesticide manufacturer and approved by the Environmental Protection Agency before their registration and release to the public. Pesticide applicators should be aware that the pesticide label is an official and binding contract between the chemical manufacturer, United States EPA, and the purchaser of the product. If the label directions are not followed, the applicator may be subject to prosecution resulting in penalties which may include fines and imprisonment.

Pesticide Selection and Use BMPs

  • Select turfgrass species and varieties which are insect and disease resistant.
  • Use pesticides which have a low pesticide leaching potential (PLP) index, when possible.
  • (See Tables 3-5 for pesticides labeled for use in North Carolina on turf. Rates of pesticides applied are based on the maximum reported application rates in Extension publication, North Carolina Pest Control Recommendations for Turfgrass Managers, AG-408. The pesticide leaching potential (PLP) value was computed based on formulas defined by R.L. Warren and J.B. Weber in Evaluating Pesticide Movement in North Carolina Soils. Trade names listed are examples. Pesticides may be sold under other trade names.)
  • Develop and implement a quality IPM program.
  • Train employees in proper pesticide application techniques.
  • Determine the size of the area of application and mix only the quantity of pesticide needed in order to save money, avoid disposal, and protect the plants.
  • Spot treat whenever possible.
  • Read and follow all label directions. The label is a legal document.
  • Only apply pesticides labeled for the turfgrass being grown and for the area being treated.
  • Apply the pesticide correctly at the right time.
  • Note groundwater advisories on the label.
  • Mix the pesticide and load the spreader or sprayer carefully to avoid spills.
  • Mix pesticides in areas where spills may be safely contained.
  • Do not mix, apply, or dispose of chemicals within 100 feet of your well.
  • Consider closed systems for loading and mixing.
  • Triple-rinse containers, pour rinsate into tank, and spray excess on turf area. Do not exceed label rates.
  • Calibrate your spreader or sprayer. Refer to information provided with your equipment and to Extension publication, Water Quality and Sprayer/Spreader Calibration, AG-152, for complete calibration instructions.
  • Fill the spray tank away from the well or any body of water.
  • Prevent back siphoning, by keeping the fill hose above the solution level of the spray tank. Use an anti-backflow device or check valve on the fill hose.
  • Store all pesticides in properly built and maintained storage facilities.

Pesticide Leaching Potential Indices

Skip to Pesticide Leaching Potential Indices

Table 3. Herbicides.
Common Name Trade Name Rate* Index**
Fenoxaprop Acclaim 0.18 0
Prodiamine Barricade 0.75 1
Diclofop Illoxan 1.50 10
Pendimethalin Pre-M 3.00 18
Dithiopyr Dimension 0.50 20
Metolachlor Pennant 4.00 22
Sethoxydim Vantage 0.28 26
MSMA MSMA 3.00 27
Trifluralin Treflan 3.00 32
Pronamide Kerb 1.50 34
Glyphosate Roundup 4.00 36
Oxadiazon Ronstar 3.00 36
Benefin Balan 3.00 36
Bentazon Basagran 2.00 36
DCPA Dacthal 10.50 38
Ethofumasate Prograss 1.00 41
2,4-D 2,4-D 0.75 41
DSMA Methar 5.00 41
Metsulfuron DMC 0.10 42
Isoxaben Gallery 1.00 44
Bensulide Betasan 10.00 44
Oryzalin Surflan 3.00 44
Napropamide Devrinol 3.00 46
Asulam Asulox 2.00 47
Metribuzin Sencor 0.50 48
Atrazine Aatrex 2.00 52
Triclopyr Turflon 2.00 53
Simazine Princep 2.00 54
Dicambia Banvel 0.50 54
Imazaquin Image 0.50 58
Mecoprop MCPP 1.75 61
Siduron Tupersan 10.00 64
* Maximum recommended application rate (lb A.I./Acre)
** Pesticide Leaching Potential Index (0 - 100) where 0 = very low leaching potential and 100 = very high leaching potential.

Table 4. Fungicides.
Common Name Trade Name Rate* Index**
Vinclozolin Curlan 2.70 20
Fosetyl-Al Aliette 17.40 25
Thiophanate methyl Clearys 3336 2.70 31
Anilazine Dyrene 5.40 31
Iprodione Chipco 2.50 33
Mancozeb Fore 8.70 36
Triadmimefon Bayleton 1.30 43
Propiconazole Banner 1.50 45
Chlorothalonil Daconil 19.60 46
Metalaxyl Subdue 1.36 50
Propamocarb Banol 7.24 51
Fenarimol Rubigan 2.00 51
Chloroneb Terraneb 7.00 51
Benomyl Tersan 2.70 55
Maneb Manzate 13.00 56
Etridiazole Koban 6.50 65
* Maximum recommended application rate (lb A.I./Acre)
** Pesticide Leaching Potential Index (0 - 100) where 0 = very low leaching potential and 100 = very high leaching potential.

Table 5. Insecticides.
Common Name Trade Name Rate* Index**
Cyfluthrin Tempo 0.09 0
Permetrin Astro 0.90 12
Fenoxycarb Award 1.50 19
Chlorpyrifos Dursban 1.00 19
Fenamiphos Nemacur 10.00 36
Acephate Orthene 3.00 36
Fonofos Crusade 3.90 37
Bendiocarb Turcam 4.10 38
Carbaryl Sevin 2.10 39
Diazinon Diazinon 4.30 41
Isofenphos Oftanol 1.90 44
Isazofos Triumph 2.00 44
Methomyl Lannate 1.90 51
Trichlorfon Proxol 8.16 52
Ethoprop Mocap 4.90 55
Propoxur Baygon 8.10 76
* Maximum recommended application rate (lb A.I./Acre)
** Pesticide Leaching Potential Index (0 - 100) where 0 = very low leaching potential and 100 = very high leaching potential.

Pesticide Storage and Disposal

Skip to Pesticide Storage and Disposal

The best way to manage pesticide storage and disposal is to reduce the amount of pesticides left over after applications through proper planning and equipment calibration. Faulty or improperly managed storage facilities may result in direct runoff or leaching of pesticides into surface and groundwaters. You and others may be held liable for damages suffered from improperly stored or disposed of pesticides.

A good storage facility should possess the following features:

  • A secure area where unauthorized persons are restricted from entering
  • Proper labeling such as No Smoking and Warning Pesticide Storage signs
  • Limited opportunity for water damage
  • Temperature control
  • A location at least 50 feet from any body of water or stream where possible water damage is limited  Nonporous floors and materials and equipment to contain and cleanup pesticide spills
  • Adequate lighting and ventilation
  • Capability of containing runoff from spills
  • Source for clean water
  • Freedom from combustible materials or debris

Pesticide Storage and Disposal BMPs

  • Maintain and follow labels on all pesticide containers.
  • Store pesticides only in original containers or make sure the new container is properly labeled.
  • Store like pesticides together. For example, store herbicides with herbicides and fungicides with fungicides.
  • Keep containers closed tightly.
  • Watch for damaged containers.
  • Store pesticides which may be flammable separately.
  • Maintain an up-to-date inventory of pesticides.
  • Purchase only the amount you need.
  • Comply with Emergency Planning and Right-to-Know regulations.
  • Triple-rinse empty containers and puncture, crush, and recycle them. You can also take them to a landfill.
  • Apply the rinsate to a labeled site at no more than labeled rates or save the rinsate and use it to make up water for similar applications. Do not release rinsate in uncontained areas.

Pesticide Spills

Skip to Pesticide Spills

Unmanaged spills may quickly move into surface waters and cause injury to plants and animals. It is essential that lawn care managers be prepared for both major and minor spills.

Pesticide Spill BMPs

  • Locate and control the source.
  • For small spills, use kitty litter, vermiculite, shredded newspaper, adsorbent pillows or pads. Direct large spills away from ditches, storm drains, ponds, or wells via dikes.
  • Place contaminated material in plastic container for disposal.
  • Encourage employees to report spills as soon as possible.
  • Call Chemtrec, a 24-hour emergency service regarding spill management, for specific instructions onsite neutralization. (800-424-9300).

Storage Tanks

Skip to Storage Tanks

Underground storage tanks are frequently used for petroleum storage. However, a leaking underground storage tank represents a fire and explosion hazard as well as a fume hazard, and represents a serious threat to groundwater. The safety concern related to environmental contamination of groundwater with hydrocarbons is potential exposure to benzene and ethyl dibromide which are suspected to be cancer causing agents.

Piping failure, spills and overfills, and tank corrosion are the main causes of leaks from underground storage tanks. The EPA estimated that 80 percent of all spills were the result of failure or fatigue of piping systems. Many of these failures were caused by improper installation and maintenance. The corrosion of tank walls and the failure of fiberglass reinforced tanks are other leading causes.

An aboveground storage tank with containment walls is the preferred method of storing chemicals. For more information contact your local fire marshal.

Given the difficulty and the cost of cleanup, you need to monitor any underground storage tanks at the site closely. Specific preventative measures include installation of double-walled tanks, early detection of leaks, inventory control, monitoring, and tightness testing.

Water quality should be considered in all stages of lawn care and maintenance. Some factors to consider have been outlined in this publication. Help to protect one of our most precious resources.


Skip to Acknowledgment

The authors gratefully acknowledge the cooperation and technical support of the following individuals:

C.E. Hartwiger, Graduate Student in Crop Science
G.R. Taylor, Graduate Student in Crop Science


Professor Emeritus
Crop and Soil Sciences

Find more information at the following NC State Extension websites:

Publication date: Jan. 1, 2001

N.C. Cooperative Extension prohibits discrimination and harassment regardless of age, color, disability, family and marital status, gender identity, national origin, political beliefs, race, religion, sex (including pregnancy), sexual orientation and veteran status.