Virginia Administrative Code › Title 12 - HEALTH › Agency 5 - DEPARTMENT OF HEALTH › Chapter 610 - SEWAGE HANDLING AND DISPOSAL REGULATIONS › Part V - Design and Construction Criteria › Article 11 - Nonpublic Drinking Water Supply Systems Utilized in Conjunction with Onsite Sewage Disposal Systems › Section 12VAC5-610-1170:3 - APPENDIX H. Land Disposal Criteria

Current through Register Vol. 40, No. 24, July 15, 2024
The following sections are reproduced from the
						Commonwealth of Virginia Sewerage Regulations, State Department of Health and
						State Water Control Board February 1977.
25.07 Sludge and Solids Disposal
25.07.01 General
A plan shall be provided for the disposal of sludge and
						solids from each treatment facility as part of the final engineering documents
						(cf. Section 2.04.02). Before sludge is disposed of by land application, its
						short term and long term chemical effects on the land and groundwater must be
						evaluated. The evaluation program should consider the existing industrial waste
						surveys and general characteristics of the land to be used as well as other
						appropriate information. Adequate provisions for residue disposal, air
						pollution control, soil contamination prevention and groundwater/surface water
						contamination prevention shall be provided. Sludge shall not be applied to root
						crops or crops intended for human consumption in the raw form. Disposal of
						sludge shall be in such a manner as not to cause health hazards, destroy
						vegetation, create odor and/or vector problems, render the soil unsuitable for
						future land use or create other nuisances. Land areas proposed for sludge
						disposal should be remote from inhabited dwellings, water supplies and
						shellfish areas. Disposal of sludge to open dumps is prohibited. Designs
						incorporating the use of sludge as a soil conditioner should be forwarded to
						the Department of Agriculture and Commerce by the Department for appropriate
						review and comment.
25.07.02 Land Acquisition or Control
When land application constitutes a primary means of
						sludge disposal for a facility and the facility does not possess sufficient
						alternate disposal means, the continued availability of the land shall be
						protected. Such land shall also be protected from improper concurrent uses
						during utilization periods. The means of such protection for land availability
						and from improper concurrent uses shall be determined by the Department, the
						Board and the owner at the preliminary engineering conference.
25.07.03 Sludge Stabilization and Pathogen Reduction
						Prior to Land Application
Sludge shall be subjected to a treatment process which
						will stabilize many of the organic materials present in raw sludge. Anaerobic
						digestion, composing, aerobic digestion, heat treatment, processes or chemical
						treatment processes such as high lime or chlorine dosages are considered to
						produce stabilized sludges. For some projects, it may be necessary to achieve
						additional pathogen reduction beyond that attained by stabilization.
25.07.04 Sludge Composition and Soil Evaluation
The following parameters for sludge and soil composition
						may be employed to determine the sludge classification and suitability of soils
						for sludge application. Determination of specific parameters to be run shall be
						made at the preliminary engineering conference and the results of the analyses
						shall be included as a portion of the sludge disposal plan required in
						accordance with Section 25.07.01.
Sludge
Soil
pH (pH units)
pH (pH units)
Cake or Slurry Water (percent) Total
								solids (percent)
Cation Exchange Capacity (meg/100gm)
Components
Components
Clay Content (percent) Organic Matter
								(percent) Total Nitrogen Organic Nitrogen Ammonia Nitrogen Total Phosphorus
								Available Phosphorus Boron Exchangeable Potassium Sodium Magnesium Iron Copper
								Nickel Chromium Zinc Lead Manganese Cadmium Mercury
Organic Matter Total Kjeldahl Nitrogen Ammonia
								Nitrogen Nitrates Nitrites Chlorides Phosphates Potassium Alkalinity as CaCO
								Boron Magnesium Chlorinated Hydrocarbons Copper Nickel Chromium Zinc Manganese
								Cadmium Mercury Lead
Micro-organisms Total Coliforms (MPN/100
								gms. sample)
Drainage Characteristics Soil profile
Fecal Coliforms (MPH/100 gms. sample)
Soil Depth
*unless otherwise noted, parameters
								shall be reported in mg/kg on a dry weight basis.
Appendix J contains forms which are recommended for use
						by the owner of the treatment facility in providing the results of background
						sludge and soil analyses. A one-quart soil sample shall be taken from the top
						four inches of soil and retained indefinitely.
After the sludge disposal plans required in accordance
						with Section 25.07.01 is approved by the Department and the Board, the
						Department and the Board waive the requirement for the sludge composition
						analyses and soil evaluation at any new application site for which either of
						the two following criteria apply:
a.
					 the sludge is applied as a single application not to be repeated for at least
					 five years.
b. the sludge
					 application area is no larger than 10 acres.
This waiver in no way limits the powers of the Board and
						the Department in the control of any sludge application practice, regardless of
						frequency of application or size of the application area, for which groundwater
						contamination, surface runoff, soil toxicity, health hazards or nuisance
						conditions are considered to be a problem or a potential problem. Additionally,
						all other requirements contained in Section 25.07 including protection from
						improper concurrent uses, stabilization, sludge classification, application and
						disposal methods, soils, application rates, runoff control, sludge transport,
						etc. shall apply to all sludge application sites, regardless of size. As a
						further condition of this waiver provisions, the plant owner shall provide
						advance notification for concurrence to the appropriate Regional Offices of the
						Department and the Board of any new site(s) for which sludge application is
						intended. The notification for concurrence may be made by phone call to be
						confirmed in writing or by letter mailed in time to ensure receipt by the
						Department and Board prior to utilization of the new site(s). As a minimum, the
						notification for concurrence shall provide the location and size of the area,
						owner's name, proposed application rate, percentage of solids and any special
						or unusual conditions which may exist.
25.07.05 Sludge classification
Prior to land application, sludge shall be evaluated in
						accordance with Section 25.07.03 and 25.07.04. The sludge shall be classified
						by its characteristics. For new projects, sludge characteristics may be
						approximated by data obtained from like treatment facilities receiving flow
						from similar waste contributors. Pilot studies for sludge characteristics may
						be required when deemed appropriate by the Department and the Board.
a. Class A-Class A sludge shall be suitable
					 for land application at the approved site in accordance with the approved
					 application conditions indefinitely under proper management. Sludge which is
					 classified as Class A shall be stabilized and shall not contain heavy metals or
					 other undesirable components in quantities that (1) may be harmful to the
					 production of crops, trees or other vegetation; (2) may result in crops or
					 vegetation containing components which may be harmful to the health of animals
					 or humans when consumed; (3) may render the soil unsuitable for future land use
					 and (4) degrade existing groundwater quality. Appendix K presents standards for
					 Class A sludge based on maximum allowable levels of certain heavy
					 metals.
b. Class B-Class B sludge
					 is sludge which is raw, partially stabilized, chemically or bacteriologically
					 contaminated or contains undesirable components which makes it unfit for land
					 application. This shall include unstabilized pumpage from septic tanks.
					 Disposal of Class B sludge may be implemented by (1) conveyance to sewage
					 treatment plant having approved sludge handling facilities, provided that
					 detrimental effects to the plant shall not occur; (2) stabilization of sludge
					 such that it shall meet the requirements of Section 25.07.05a, above; and (3)
					 other methods which will be evaluated on a case by case basis. Raw or partially
					 stabilized sludge shall be mixed with solid waste for disposal in solid waste
					 landfills.
25.07.06 Application and Disposal Methods
Spray application of Class A sludge to the land is
						acceptable when no transport of aerosols beyond the boundaries of the
						application area is predicted.
a.
					 Liquid Sludge
Liquid sludge shall generally have a solids content of
						less than 12 percent. Liquid Class A sludges shall be applied to land by
						plowing, discing, or direct injection so that the sludges are immediately
						covered or by spraying or spreading on pasture that has been clipped short,
						permanent crop land or land that is producing trees or nursery stock. Only
						application sites especially selected for sludge application and approved by
						the Department and the Board may be used. Liquid sludges shall not be mixed
						with solid wastes for disposal in solid waste landfills.
b. Final Dewatered Sludge
Final dewatered sludge is sludge that is dewatered for
						the purpose of ultimate disposal and is defined as having a solids content
						usually ranging between 12 percent and 30 percent. Dewatered sludges including
						those dewatered through the use of centrifuges, vacuum filters and filter
						presses may be disposed with solid wastes if the ratio of sludge is high enough
						so as to prevent problems with compaction and extruding of sludges to the
						surface of the ground. These dewatered sludges may also be disposed in separate
						trenches at approved solid waste landfill sites or other approved sites.
						Dewatered Class A sludges may also be applied to the land by plowing or discing
						into the soil immediately after application or by spraying or spreading on
						pasture that has been clipped short, permanent crop land or land that is
						producing trees or nursery stock. Only application sites especially selected
						for sludge application and approved by the Department and the Board may be
						used.
c. Dried Sludge
Dried sludge is sludge that has a solids content greater
						than 30 percent. Dried Class A sludges from treatment processes may be disposed
						in solid waste landfills or atop the landfills to promote growth of vegetation,
						landfills selected for sludge disposal or plowing or discing into the ground or
						by spraying or spreading on pasture that has been clipped short, permanent crop
						land or land that is producing trees or nursery stock. Only application sites
						especially selected from sludge application and approved by the Department and
						the Board may be used.
d.
					 Other Solids
Grit, rages and other debris or screenings from sewage
						treatment plants shall be stored in covered containers. These solids are
						classified as Class B, and subsequent disposal shall be by burial at solid
						waste landfill sites or other sites approved by the Department and the
						Board.
25.07.07 Soil
Soils shall be well drained. A minimum soil depth of two
						feet is preferred.
25.07.08 Application Rates
For land application systems, the engineer shall consider
						sludge composition, soil characteristics, climate, vegetation, cropping
						practices and other critical factors in determining application rates. Since
						sludge and site factors vary widely, application rates shall be determined for
						each specific site. Application rates shall be approved by the Department and
						the Board.
Nitrogenous substances are usually the limiting factor in
						determining annual application rates. Unless it can be satisfactorily
						demonstrated that the nitrogen uptake of crops to be harvested justifies a
						higher loading rate, the initial design application rate shall not exceed five
						tons of dry weight solids/acre/year. Guidelines for allowable application rates
						for specific crops are presented in Appendix K. Additionally, Appendix K
						presents guidelines on maximum loadings of cadmium, maximum cumulative levels
						for metals and acceptable soil pH levels. For any site receiving only a single
						application of sludge not to be repeated for at least five years, the maximum
						allowable loading rate for the on-time application shall be 15 tons of dry
						weight solids/acre. The above notwithstanding, at no time shall sludge be
						applied to a depth greater than 0.5 inches in any single application
						procedure.
No crops should be removed by harvesting or grazing less
						than 30 days after the last application of sludge. Pasture should be clipped
						immediately prior to sludge application.
25.07.09 Groundwater Quality
Land application sites, landfills, sludge lagoons and
						sludge holding facilities shall be designed and operated so that the
						utilization of sludge does not result in groundwater quality changes. If the
						presently existing concentration of any parameter is high in the groundwater
						than the level allowed for a raw water supply source (reference: Commonwealth
						of Virginia Waterworks Regulations), then the sludge utilization or disposal
						technique shall not result in an increase in the concentration of that
						parameter.
25.07.10 Holding Facilities
a. Emergency Holding
Raw sludges, septic tank sludges, sludges from upset
						digesters and sludges of similar nature may be stored in emergency holding
						facilities. Subsequent processing of the supernatant and sludge shall be
						provided in an approved manner. Such holding facilities should be located
						remote from human activity. The engineer shall provide a plan for approval by
						the Department and the Board. The plan shall address sampling, odor control,
						vector control, potential soil and water pollution, and security.
b. Routine Holding
During periods when application of sludges to
						agricultural land is not possible due to climatic or other conditions, a
						holding facility shall be provided. The engineer shall provide a mass balance
						which determines the amount of sludge storage which is to be provided. The
						location and protection of the holding facility shall conform to the
						requirements stated in Section 25.07.01a, above. Holding shall be utilized to
						enhance runoff prevention.
25.07.11 Incineration
Incineration of sludges and screenings from treatment
						facilities is an approved method of solids reduction. Such facilities shall
						meet all requirements for air pollution control. The ash from such processes
						may be buried or spread on land selected for such purposes and approved by the
						Department and the Board.
25.07.12 Sludge Lagoons
a. Long Term Storage Lagoons
Long term storage lagooning of stabilized sludges is
						allowable if provisions are made for ultimate disposal of the sludge in
						accordance with the requirements of the section. Decant liquid from the lagoon
						shall be conveyed to a plant by an approved method for treatment in a manner
						that will not upset the plant's operational efficiency. Adequate provisions
						shall be made to prevent seepage from the lagoon. Fencing and warning signs
						shall be required.
b.
					 Ultimate Disposal Lagoons
Lagooning of stabilized sludges as a means of ultimate
						disposal is allowable if stored in accordance with Section 25.07.12a above and
						covered with soil upon completion of use to a depth of two feet.
25.07.13 Transport of Sludge
The engineer shall furnish the final engineering
						documents (Section 2.03) the equipment and materials needed for sludge
						handling, including nonspill, water-tight vehicles for transport, routes,
						quantities of sludge and procedures to be used. Transport vehicles should be
						equipped with tow hooks, and transport routes through heavily populated areas
						should be avoided.
25.07.14 Land Reclamation
Land reclamation is an accepted practice usually
						utilizing high application rates of liquid sludge. Class A sludges are
						acceptable for land reclamation. The sludge utilization program shall be
						developed between the owner, the Department, the Board, the Division of Mined
						Land Reclamation (when appropriate) and other agencies as appropriate.
25.07.15 Other Methods
Other methods of sludge and solids disposal, such as
						preparation and use as a soil conditioner, will be considered on a case by case
						basis.
25.07.16 Runoff Prevention
An area which has sludge applied by spraying or spreading
						shall be located a minimum distance of 50 feet from all surface water.
						Containment and controlled release of runoff from sludge application areas or
						effective erosion control methods should be practiced as necessary.