Natural resource inventory town of hammonton, atlantic county
TABLE 4 GROUNDWATER QUALITY CRITERIA – CLASS GW-2
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- TABLE 4 (Continued) GROUNDWATER QUALITY CRITERIA – CLASS GW-2 SECONDARY STANDARDS
- TABLE 5 GROUNDWATER QUALITY CRITERIA – CLASS GW-1
- SECTION 5.00 Soils
- TABLE 6 SELECTED CHARACTERISTICS OF SOILS AS DESCRIBED BY THE U.S. SOIL CONSERVATION SERVICE
- 5.01 Soils Septic Disposal Field Function
TABLE 4 GROUNDWATER QUALITY CRITERIA – CLASS GW-2 PRIMARY STANDARDS / TOXIC POLLUTANTS Pollutant, Substance or Chemical Groundwater Quality Criteria 1. Aldrin/Dieldrin 1. 0.002 ug/l 2. Arsenic & Compounds 2. 0.02 ug/l 3. Barium 3. 2,000 ug/l 4. Benzidine 4. 0.0002 ug/l 5. Cadmium & Compounds 5. 4 ug/l 6. Chromium (Hexavalent) & Compounds 6. 70 ug/l 7. Cyanide 7. ??? 8. DDT and Metabolites 8. 0.1 ug/l 9. Endrin 9. 2 ug/l 10. Lead & Compounds 10. 5 ug/l 11. Mercury & Compounds 11. 2 ug/l 12. Nitrate-Nitrogen 12. 10,000 ug/l 13. Phenol 13. 2,000 ug/l 14. Polychlorinated Biphenyls 14. 0.02 ug/l 15. Radionuclides 15. Prevailing regulations adopted by the USEPA pursuant to Sections 1412, 1415, and 1450 of the Public Health Services Act as amended by the Safe Drinking Water Act (PL 93-523) 16. Selenium & Compounds 16. 40 ug/l 17. Silver & Compounds 17. 40 ug/l 18. Toxaphene 18. 0.03 ug/l
20. Chloride 20. 250,000 ug/l 21 Coliform Bacteria 21. a) by membrane filtration, not to exceed four (4) per 100 ml in more than one (1) sample when less than twenty (20) are examined per month, or
b) by fermentation tube, with a standard 10 ml portion, not to be present in three (3) or more portions in more than one (1) sample when less than twenty (20) are examined per month OR c) prevailing criteria adopted pursuant to the Federal Safe Drinking Water Act (PL 93-523). 22. Color 22. 10 cu 23. Copper 23. 1,300 ug/l 24. Fluoride 24. 2,000 ug/l 25 Foaming Agents 25. 500 ug/l 26. Iron 26. 300 ug/l 27. Manganese 27. 50 ug/l 28. Odor & Taste 28. 3 29. Oil & Grease & Petroleum Hydrocarbons 29. None Noticeable 30. pH (Standard Units) 30. 6.5-8.5 31. Phenol 31. 2,000 ug/l 32. Sodium 32. 50,000 ug/l 33. Sulfate 33. 280,000 ug/l 34. Total Dissolved Solids (TDS) 34. 500,000 ug/l 35. Zinc & Compounds 35. 2,000 ug/l 36. BOD (5-day) 36. 3 mg/l 37. Phosphate, Total 37. 0.7 mg/l Groundwater Class GW-1 Designated Uses: Class GW-1 groundwater in the Central Pine Barrens shall be suitable for potable water supply, agricultural water supply, continual replenishment of surface waters to maintain the existing quantity and high quality of the surface waters in the Central Pine Barrens, and other reasonable uses. TABLE 5 GROUNDWATER QUALITY CRITERIA – CLASS GW-1 Standards for Class GW-1 are identical to Class GW-2 in Table 4 above, except the following substances which have stricter quality criteria as indicated. Pollutant, Substance or Chemical Groundwater Quality Criteria 5. Cadmium & Compounds 5. Natural Background 6. Chromium (Hexavalent) & Compounds 6. Natural Background 12. Nitrate-Nitrogen 12. 2.0 mg/l 13. Phenol 13. 0.3 mg/l 16. Selenium & Compounds 16. Natural Background 20. Chloride 20. 10 mg/l 30. pH (Standard Units) 30. 4.2 – 5.8 32. Sodium 32. 10 mg/l 33. Sulfate 33. 15 mg/l 34. Total Dissolved Solids (TDS) 34. 100 mg/l SECTION 5.00 Soils All soils have various physical and chemical properties which define their capability to support different types and intensities of land development. The environmental sensitivity, or development potential of any site can be defined by naturally occurring conditions of its environment, and soils are a primary indicator of those conditions. Soils are classified in two ways; by series and by phase. A series includes soils with similar subsurface properties and origin. These are further refined into phases according to other characteristics such as slope, degree of susceptibility to erosion, stoniness, and surface composition or texture. All soils were formed through the interaction of five major factors; parent material, climate, plant and animal life, relief, and time. The Town of Hammonton's soils were all formed from the same parent material, those unconsolidated sandy and gravelly deposits of the Atlantic Coastal Plain which were deposited, redistributed, stratified, and eroded during successive rises and retreats of sea level over recent geologic history. Such soils are generally porous and acidic, with a generally low capacity to retain both water and nutrients. The Atlantic County Soil Survey, prepared by the United State Department of Agriculture in cooperation with the Soil Conservation Service, Cape-Atlantic District has identified those phases of major soil series occurring within the Town of Hammonton (See Map No. 4). Twenty-six (26) different soil types have been identified within the Town of Hammonton and have been determined to occupy the following acreages and percentages of the total land area of the Town. SOIL TYPE MAP SYMBOL ACRES PERCENT 1. Atsion sand AtsA 4255.33 16.78% 2. Atsion-Berryland sand AttxAr 1765.45 6.96% 3. Aura loamy sand AucB 71.18 0.28% 4. Aura sandy loams AugB 691.44 2.72% 5. Aura soil, Ironstone variant AwbB 176.35 0.69% 6. Berryland sand BerAr 893.30 3.52% 7. Berryland sand, flooded BerAt 303.15 1.19% 8. Downer loamy sand DocB 1957.00 7.71% 9. Downer sandy loam DosA 427.56 1.68% 10. Evesboro sand EveB 1499.91 5.91% 11. Evesboro sand, clayey substratum EvekB 234.00 0.92% 12. Fort Mott sand FobB 119.20 0.47% 13. Galloway loamy sand GamB 1676.32 6.61% 14. Galloway loamy sand, clayey substratum GamkB 384.77 1.51% 15. Hammonton loamy sand HbmB 1224.60 4.83% 16. Hammonton loamy san, clayey substratum HmkB 93.47 0.36% 17. Hammonton sandy loam HboA 1147.68 4.52% 18. Hammonton sandy loam, clayey substratum HbokA 104.50 0.41% 18. Lakehurst sand LakB 2192.45 8.64% 19. Lakewood sand LasB 1623.50 6.40% 20. Lakewood sand, 5 to 10 percent slope LasC 46.57 0.18% 21. Manahawkin Muck MakAt 2664.47 10.50% 22. Matawan sandy loam MbtB 119.89 0.47% 23. Pits, Sand and Gravel PHG 159.89 0.63% 24. Psamments PssA 123.71 0.48% 25. Sassafras sandy loam SacA 775.15 3.05% 26. Sassafras sandy loam, 2 to 5 percent slopes SacB 255.85 1.01% 27. Water WATER 154.37 0.60% 28. Woodstown sandy loam WoeA 212.58 0.83% It is not the purpose of this resource inventory to duplicate information readily available from other sources, and an extensive compilation of soils information is available in the Soil Survey of Atlantic County, New Jersey which may be obtained through the Soil Conservation Service, Cape-Atlantic District offices in Mays Landing. The survey lists engineering and agricultural characteristics of each soil type, most of which are of interest in determining the appropriateness of different types of development on a given soil type. Characteristics such as flood hazard, depth to seasonal high groundwater level, suitability of soils for such uses as playgrounds and housing with or without basements are just a few of the listings contained within the Soil Survey. Some of the more important development limitations imposed by the presence of certain soil types are discussed herein in Table 6-6, but it is still recommended that the above mentioned guide be consulted for a more detailed listing of soil characteristics and limitations. There is one (1) significant change to the Soil Survey information which should be pointed out as a result of the Pinelands Protection Act legislation. The Soil Survey lists a number of soil types as having slight or moderate limitations for septic disposal systems which are, in fact, now considered unsuitable for such use. According to the Pinelands Management Plan, any site which has less than a depth of five feet (5') to the seasonal high groundwater level is unsuitable for conventional septic systems. This updated information is reflected in Map 5 at the end of this inventory which deals with septic suitability. There are considerations other than water table, such as percolation rate, presence of clay, etc., for evaluating sites for septic systems, but limitations posed by such other factors can usually be corrected by excavating the natural soil and replacing it with more suitable filter material, for example. There is no acceptable way of lowering the groundwater table, however, so in cases where it rises to within five feet (5') or closer to the surface seasonally, conventional septic systems are not suitable. Although the information relating to soil types is valid and accurate with the one exception noted above, great care must be taken to ensure that the soils on any site-in-question are in fact what they are indicated to be. Due to the age of the soil survey and the mapping methods used, the delineation of soil type boundaries is sometimes questionable, and the accuracy of soils information should always be verified through on-site borings and field evaluation by a qualified professional. Because of the scale and methods which were used to map soils originally, it is not unusual for soil boundary lines to be mislocated by up to one hundred feet (100') or more in some cases. In the case of a large tract of land, this may have no significant effect on overall development, although the site plan should reflect the accurate location of any sensitive soil areas which may exist on the property. In the case of a smaller property, a one hundred foot (100') soil boundary mislocation could have significant effects on developability if one of the soils has limitations for the type of development proposed. A second common shortcoming of the mapped soils information is that in many cases, intermediate or transitional soils are not mapped separately, but fall within areas designated as upland or lowland soil types. Whenever a soil type with a 0 to 1' depth to seasonal high groundwater, for example, adjoins a soil type with a 5' or greater depth to groundwater, it is obvious that some intermediate (1½' to 5' depth to groundwater) soil has not been mapped in that transitional zone. In such cases, on-site borings are the only sure way of locating the actual extent of the intermediate soil type. Such information could be quite significant, especially if the proposed development includes the installation of a septic disposal system which requires that the seasonal high groundwater level be at least five feet (5') below the surface. In areas where public sanitary sewer is available, residential development is normally permitted in areas where the depth to seasonal high groundwater is in the intermediate range (1½' to 5'). For these reasons, the accurate location of all soil boundaries is necessary and should be required as a standard development application requirement. Characteristics of soils which may pose limitations for development of certain types have been identified in the Atlantic County Soil Survey. These limitations are rated as follows: 1. A "Slight" rating means little or no limitation for the specified use, and any limitation which exists is easily corrected by the use of conventional practices of construction and use of normal equipment. 2. A "Moderate" rating means the presence of some limitation for the specified use, which can normally be overcome by careful design and management, however, at somewhat greater costs than for soils with a slight limitation. 3. A "Severe" rating means that the limitations are those which cannot normally be overcome except with costly and/or complex measures. Table 6 describes the characteristics of those soils occurring in the Town of Hammonton which are of most importance for determination of a site's suitability for development. Again, note that "Moderate" ratings have been listed for a number of soils in regard to septic filter field limitations, but those soils with a seasonal high water table of less than five feet (5') are now unacceptable for installation of septic systems in the Pinelands Area. This change has been incorporated in Table 6 with a note where it deviates from the Soil Survey information to reflect updated standards for septic suitable soils. TABLE 6 SELECTED CHARACTERISTICS OF SOILS AS DESCRIBED BY THE U.S. SOIL CONSERVATION SERVICE
Permeability Class Numerical Range (in/hr) (1) Flood Hazard Slow Less than 0.2 (2) Possible Groundwater Pollution Hazard Moderate-Slow 0.2 to 0.6 (3) Frost Action Potential Moderate 0.6 to 2.0 (4) Slow Permeability Moderate-Rapid 2.0 to 6.0 (5) High Groundwater Table Rapid More than 6.0 * Permeability Classes: Estimated rates at which water percolates through the least permeable soil layer. + Soils with a seasonal high water table of less than 5 feet are unacceptable for installation of septic systems in the Pinelands Area. 5.01 Soils & Septic Disposal Field Function Soils vary in their capacity to remove pollutants from percolating septic effluent. Sands are relatively poor purifiers as shown in the following diagram, Figure 5. FIGURE 5 Suitability and Limitations of Various Soil Types for Renovation of Septic Effluent. (Limitations and potential problems increase with band width.) Sandy Loam Silty Loam To CONDUCTIVITY TYPE Sand To Loam Silty Clay Loam Clay Pathogenic Purification ? N
itrogen Removal Phosphorus Removal BOD + Solids Removal Biological Clogging
Compaction & Puddling SOURCE: N.J. Pinelands Comprehensive Management Plan. Septic tank effluent is widely variable in composition. The size and design of the septic tank, the degree of sludge and scum accumulation in the tank, tank-water detention time and waste flow rates all determine the effectiveness with which contaminants are removed from the waste stream. Initial treatment by the septic tank functions to remove most of the suspended solids by sedimentation. Anaerobic conditions initiate chemical and biological alteration of sewage constituents. Partially renovated effluent is then discharged to the soil via the drainfield, which distributes the effluent load as evenly as possible over the entire disposal area. The soil provides final treatment of the wastewater before its loss to either evapotranspiration or deep percolation. A key to the effectiveness of the standard septic system is the biological crust or "mat" which forms at the boundary of the trench fill and the undisturbed soil. Crusting can be beneficial, since the organic layer serves as an effective degradative filter for suspended and dissolved organic matter. Also, aerobic, unsaturated flow conditions are encouraged in the soil beside and below the disposal trench. Unsaturated flow conditions enhance the purification of the effluent through filtration, sorption, and oxidation, and it is for these reasons that the depth to seasonal high groundwater level in soils is of such importance for the location of a septic disposal bed. If groundwater rises to the level of trench discharge, effluent will contact and flow into groundwater in an untreated condition, thereby causing contamination of the groundwater and rendering it unsuitable for consumption. Nitrogen is of primary importance in the renovation of sewage effluent because excessive concentrations in groundwater can pose a public health hazard and contribute to the eutrophication of surface waters. Eutrophication is the over-enrichment of water with nutrients which leads to excessive growth of aquatic plants, and is especially prevalent in small, shallow lakes such as those common to the Pinelands. Phosphorus is another element of wastewater which contributes heavily to eutrophication when it reaches surface water bodies via the groundwater. Diseases transmitted by waterborne pathogens, such as typhoid fever, dysentery, and hepatitis can also move through the soil with septic effluent. All the above, Nitrogen, Phosphorous, and pathogens are effectively removed from wastewater, however, in a properly functioning septic disposal system. But the most important single factor is having an adequate depth of unsaturated soil between the disposal bed and the high groundwater level. The minimum allowable depth of unsaturated soil at the time of seasonal high groundwater level has been set at five feet (5') below the natural ground surface by the standards of the Pinelands Comprehensive Management Plan. This depth has been established because during construction of the septic system, distribution lines and fill rock may typically extend three feet (3') below the surface, leaving a minimal effective twenty-four inch (24") layer of natural soil for aerated percolation of septic effluent above the saturated zone. Many of the standards and regulations implemented by the Pinelands Management Plan are the result of scientific evidence which was compiled and evaluated during formulation of the Plan. The protection of surface and groundwater quality and quantity was a major objective of the Pinelands Protection Act, and is reflected in the regulations imposed by the Comprehensive Management Plan. Download 1.1 Mb. Share with your friends:
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