1、Designation: D 5879 95 (Reapproved 2003)Standard Practice forSurface Site Characterization for On-Site Septic Systems1This standard is issued under the fixed designation D 5879; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the y
2、ear of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers procedures for the characterizationof surface conditions at a site for evaluating suitabi
3、lity for anon-site septic system for disposal and treatment of wastewater.This practice provides a method for identifying potentiallysuitable areas for soil absorption of septic tank wastewater.1.2 This practice can be used at any site where on-sitetreatment of residential and nonhazardous commercia
4、l waste-waters using septic tanks and natural soils or constructed filterbeds is required or an option under consideration. This practicemay also be useful when constructed wetlands are used as analternative wastewater treatment method.1.3 This practice should be used in conjunction with Prac-tices
5、D 5921 and D 5925.1.4 This practice offers a set of instructions for performingone or more specific operations. This document cannot replaceeducation or experience and should be used in conjunctionwith professional judgment. Not all aspects of this practice maybe applicable in all circumstances. Thi
6、s ASTM standard is notintended to represent or replace the standard of care by whichthe adequacy of a given professional service must be judged,nor should this document be applied without consideration ofa projects many unique aspects. The word “Standard” in thetitle of this document means only that
7、 the document has beenapproved through the ASTM consensus process.2. Referenced Documents2.1 ASTM Standards:2D 5921 Practice for Subsurface Characterization of Test Pitsfor On-Site Septic SystemsD 5925 Practice for Preliminary Sizing and Delineation ofSoil Absorption Field Areas for On-Site Septic S
8、ystem3. Terminology3.1 clinometer, nan instrument for measuring inclination,as in topographic slope.3.2 constructed filter bed, na material, usually of a sandytexture, placed above or in an excavated portion of the naturalsoil for filtration and purification of wastewater from an on-siteseptic syste
9、m.3.3 on-site septic system, nany wastewater treatment anddisposal system that uses a septic tank or functionally equiva-lent device for collecting waste solids and treats wastewaterusing natural soils, or constructed filter beds with disposal ofthe treated wastewater into the natural soil.3.4 poten
10、tially suitable field area, nthe portions of a sitethat remain after observable limiting surface features, such asexcessive slope, unsuitable landscape position, proximity towater supplies, and applicable setbacks, have been excluded.3.5 recommended field area, nthe portion of the poten-tially suita
11、ble field area at a site that has been determined to bemost suitable for an on-site septic system soil absorption fieldor filter bed based on surface and subsurface observations.3.6 soil absorption area, nan area of natural soil used forfiltration and purification of wastewater from an on-site septi
12、csystem.3.7 soil absorption field area, nan area that includes soilabsorption trenches and any soil barriers between the trenches.Also called a leachfield.3.8 soil absorption trench, nan excavated trench, usually1.5 to 3 ft wide that receives wastewater for treatment. Alsocalled a lateral or leachli
13、ne.4. Summary of Practice4.1 This practice describes a procedure using existing infor-mation about a site, simple field equipment, and visual obser-vation for identifying and evaluating all significant conditionsat the surface of a site, including climate, vegetation, topogra-phy, surface drainage,
14、water sources, and human influences(structures, property lines), that may affect the suitability fordesign and construction of an on-site septic system. Theprocedure involves exclusion of areas that are unsuitable fornatural soil absorption or constructed filter beds as a result oftopography, landsc
15、ape position, and proximity to surface1This practice is under the jurisdiction of ASTM Committee D18 on Soil andRock and is the direct responsibility of Subcommittee D18.01 on Surface andSubsurface Characterization.Current edition approved Dec. 10, 1995. Published February 1996.2For referenced ASTM
16、standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohock
17、en, PA 19428-2959, United States.drainage, water sources, and other limiting surface character-istics (structures, utilities, property lines). If no areas at a sitecomply with applicable regulatory requirements, no additionalfield investigations are required. This procedure also providesguidance on
18、selection of the specific area or areas at a site forsubsurface investigation as covered in Practice D 5921.5. Significance and Use5.1 This practice should be used as the initial step forevaluating a site for its potential to support an on-site septicsystem and to determine the best location for sub
19、surfaceobservations as covered in Practice D 5921.5.2 This practice should be used by individuals involvedwith the evaluation of properties for the use of on-site septicsystems. Such individuals may be required to be licensed,certified, or meet minimum educational requirements by thelocal or state r
20、egulatory authority. Generally, such individualsshould be familiar with the appropriate regulatory requirementsgoverning the design and placement of on-site septic systemsfor the area of the site being investigated, and at least someexperience or training in geomorphology, soils, geology, andhydrolo
21、gy.35.3 This practice is one step in the design of an on-siteseptic system that also includes subsurface characterization,see Practice D 5921, staking and protection of the soil absorp-tion or constructed filter bed area, see Practice D 5925,selection of system type, and design of the system size an
22、dconfiguration. Typically, the same individual will perform thesurface and subsurface characterization of a site. Local regu-lation and practice will determine whether the same individualis responsible for all steps in the process of locating anddesigning an on-site septic system. Effective surface
23、andsubsurface characterization of a site for on-site septic systems,however, requires some knowledge of the following for thecounty or state in which the site is located: (1) on-site septicsystem types typically used for different soil conditions, and(2) typical soil absorption/filter bed areas requ
24、ired for differentwastewater flow rates and areal soil wastewater loading rates.6. Field Equipment6.1 In addition to equipment identified in Practice D 5925,additional equipment useful for site surface investigationsinclude the following:6.1.1 Clinometer or Hand Level, and a Surveyors or otherrod fo
25、r slope measurements;6.1.2 Hammer, Stakes and Flagging, for marking probe orauger holes and the recommended field area. If an extendablesurveyors rod is used, a tripod for stabilizing the rod may alsobe useful. Accurate measurement of distances requires a tapemeasure (30 m or 100 ft), although for m
26、any investigationspacing may be adequate for measuring approximate distances.6.2 At some sites, surveying equipment may be required todetermine more definitively suitability for an on-site septicsystem or to provide additional information at the designstages. Examples of such situations include marg
27、inal siteswhere accurate measurements of a recommended field area arerequired to determine if the suitable area is large enough andsites where accurate topographic contours are required forengineering design of constructed filter beds. This practicedoes not address the use of surveying equipment for
28、 suchpurposes.7. Procedure7.1 Preliminary DocumentationAll readily available in-formation about the site should be obtained and reviewed priorto visiting the site.7.1.1 A survey showing the boundaries of the site is thepreferred method for locating the site because it can also serveas a base map for
29、 field observations. A legal description of theproperty can also be used to plot the site on other availablemaps or for drawing a sketch map of the site. A topographicsurvey with contour intervals of 1 to 5 ft will facilitatepreliminary identification of potentially suitable field areas andfinal map
30、 preparation. Usually, such maps will not be availableunless the site is part of a larger planned subdivision.7.1.2 The following information concerning local or stateregulatory on-site septic system siting requirements should beavailable for field reference, if required:7.1.2.1 Minimum separation d
31、istance between soil absorp-tion or constructed filter fields and water supply, property linesand other surface and subsurface features,47.1.2.2 Wastewater hydraulic loading rates for different soiltexture, structure and other field observable soil properties,57.1.2.3 Selection criteria for alternat
32、ive on-site septic sys-tem designs (that is, depth to seasonal high water table, depthto limiting soil layer, slope, and so forth), and7.1.2.4 Other site-specific features that may affect design ofon-site septic systems, such as perimeter drain clearances, andwastewater loading rates.7.1.3 If the si
33、te is undeveloped, the following informationshould be obtained, prior to visiting the site:7.1.3.1 Planned location and size of the house or commer-cial structure,7.1.3.2 Planned location of water well, if applicable, waterlines, and other buried utilities, and7.1.3.3 Information required for determ
34、ining wastewaterload rates and strength for septic system design (that is, numberof bedrooms, number of full-time employee equivalents andshifts per day, biological/chemical oxygen demand). PracticeD 5925 addresses in more detail wastewater hydraulic loadingand strength considerations in sizing on-s
35、ite septic systems.7.1.4 A published soil survey prepared by the U.S. NaturalResource Conservation Service (formerly Soil ConservationService) is the best single background reference on subsurfaceconditions for an on-site septic system field investigation.Plotting the site boundaries on the soil map
36、 and reviewinginformation in the soil survey report provide a preliminaryindication of climate, topography, geology, hydrology, and3National Small Flows Clearinghouse (NFSC), 1995. Site Evaluation from theState Regulations. NFSC, Morgantown, WV.4National Small Flows Clearinghouse (NFSC), 1995. Locat
37、ion and SeparationGuidelines from the State Regulations. NFSC, Morgantown, WV.5National Small Flows Clearinghouse (NFSC), 1995. Application Rates andSizing of Fields from the State Regulations. NFSC, Morgantown, WV.D 5879 95 (2003)2types of limiting soil conditions that may be encountered, suchas sh
38、allow bedrock or ground water.7.1.5 Potentially useful supplemental materials include: (1)USGS 7.5-ft topographic maps, (2) aerial photographs, (3) welllogs, (4) wetland inventories, (5) state and USGS geologic andhydrologic reports, and (6) adjacent or previous septic systemevaluations, designs, or
39、 permits.7.2 SchedulingThe investigation should be scheduled fora time and date that allows all parties interested or required forthe investigation to be present. People who may need to bepresent for part or all of the investigation include the propertyowner, the construction contractor, a backhoe o
40、perator, and arepresentative of the on-site septic system permitting authority.7.3 Identification of Unsuitable AreasAt a site, the char-acterization process begins with identification of all areas ofthe site that a clearly unsuitable for a wastewater soil absorp-tion field or constructed filter bed
41、. Specific exclusionaryfeatures and criteria for defining them will depend uponregulatory requirements and guidance identified in 7.1.2. Suchexclusionary features typically fall into three categories: (1)water supply separation distances, (2) other buffer zones, and(3) limiting physiographic feature
42、s. When most of the area at asite is potentially suitable, it may be possible to go directly tothe subsurface investigation phase described in 7.4.7.3.1 Water SupplyIdentify and mark on the investigationmap water supply sources (drinking water and irrigation wells,reservoirs) and water supply lines.
43、 Include both existing andplanned locations for new sources. Note minimum requiredseparation distance from on-site septic systems for all identi-fied features.7.3.2 Other Buffer ZonesIdentify and mark on the inves-tigation map all other features requiring separation distances,such as building founda
44、tions, property lines, buried utilitylines, cuts or embankments, large trees, irrigation ditches,streams, lakes, and wetlands. Include both existing and plannedlocations for new sources. Note minimum required separationdistance from on-site septic systems for all identified features.7.3.3 Limiting P
45、hysiographic FeaturesIdentify and delin-eate on the investigation map all areas that are physiographi-cally unsuitable, such as severely eroded or gullied soils,disturbed soils (cut and fill), excessively steep slopes, unsuit-able landscape position (toe slopes, concave slopes, depres-sional areas),
46、 and flood plains. Actual criteria for identifyinglimiting physiographic features will be based on regulatoryrequirements identified in 7.1.2.7.4 Subsurface InvestigationsThe area that remains afterall minimum separation distances, buffer zones, and unsuitablephysiographic features have been exclude
47、d represents thepotentially suitable field area for an on-site septic system.Subsurface observations, as covered in Practice D 5921 mayidentify unsuitable or limiting subsurface conditions that willlimit further the potentially suitable field area.7.5 Recommended Field AreaThe portion of the poten-t
48、ially suitable field area at a site that is most suitable for anon-site septic system soil absorption field or filter bed based onsurface and subsurface observations should be delineated onthe investigation map as the recommended field area. This areashould be staked and protected from disturbance d
49、uring con-struction activities as covered in Practice D 5925. PracticeD 5925 also provides guidance on the size of area that shouldbe included in the recommended field area.7.5.1 The recommended field area should include the areathat, taking into account limiting surface and subsurfaceconditions at the site, provides the greatest flexibility inselection and design of an on-site septic system. Placing thefield at a lower topographic position than the septic tank outfallallows the option of either gravity or pumped distribution ofwastewater where soils are suitable for
