HomeMy WebLinkAbout20052156.tiff 200 WELD COUNTY
CODE ORDINANCE 2005-5
IN THE MATTER OF REPEALING AND REENACTING CHAPTER 30 SEWAGE SYSTEMS, OF
THE WELD COUNTY CODE
BE IT ORDAINED BY THE BOARD OF COUNTY COMMISSIONERS OF THE COUNTY OF
WELD, STATE OF COLORADO:
WHEREAS,the Board of County Commissioners of the County of Weld,State of Colorado,
pursuant to Colorado statute and the Weld County Home Rule Charter,is vested with the authority
of administering the affairs of Weld County, Colorado, and
WHEREAS,the Board of County Commissioners, on December 28, 2000, adopted Weld
County Code Ordinance 2000-1,enacting a comprehensive Code for the County of Weld, including
the codification of all previously adopted ordinances of a general and permanent nature enacted on
or before said date of adoption, and
WHEREAS, the Weld County Code is in need of revision and clarification with regard to
procedures, terms, and requirement therein.
NOW, THEREFORE, BE IT ORDAINED by the Board of County Commissioners of the
County of Weld,State of Colorado,that existing Chapter 30 Sewage Systems, of the Weld County
Code be, and hereby is, repealed and re-enacted, as attached hereto.
BE IT FURTHER ORDAINED by the Board that the Clerk to the Board be, and hereby is,
directed to arrange for Colorado Code Publishing to supplement the Weld County Code with the
amendments contained herein, to coincide with chapters, articles, divisions, sections, and sub-
sections as they currently exist within said Code; and to resolve any inconsistencies regarding
capitalization,grammar,and numbering or placement of chapters,articles,divisions,sections, and
sub-sections in said Code.
BE IT FURTHER ORDAINED by the Board if any section,subsection,paragraph,sentence,
clause, or phrase of this Ordinance is for any reason held or decided to be unconstitutional, such
decision shall not affect the validity of the remaining portions hereof. The Board of County
Commissioners hereby declares that it would have enacted this Ordinance in each and every
section, subsection, paragraph, sentence, clause, and phrase thereof irrespective of the fact that
any one or more sections, subsections, paragraphs, sentences, clauses, or phrases might be
declared to be unconstitutional or invalid.
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The above and foregoing Ordinance Number 2005-5 was, on motion duly made and
seconded, adopted by the following vote on the 1st day of August, A.D., 2005.
/�� BOARD OF COUNTY COMMISSIONERS
EL, `s L4', � WELD COUNTY, COLORADO
William H. .erke, Chair
Clerk to the Board
M. '�`eile, ro-Tem
car
Deputy Clerk to the Board c
D-vid E. Long J
AP• ' • E�.�:p .��►' t� 'r� --
Rob- ' asd n
�•u t' ttorney
Glenn Vaa.
Publication: June 1, 2005
First Reading: June 15, 2005
Publication: June 29, 2005, in the Fort Lupton Press
Second Reading: July 11, 2005
Publication: July 20, 2005, in the Fort Lupton Press
Final Reading: August 1, 2005
Publication: August 10, 2005, in the Fort Lupton Press
Effective: August 15, 2005
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ARTICLE I
General Provisions
Sec. 30-1-10. Title.
The regulations contained herein shall also be known as the Individual Sewage Disposal
System (I.S.D.S.) Regulations.
A. Declaration. In order to preserve the environment and protect the public health;to
eliminate and control causes of disease,infection, and aerosol contamination; and
to reduce and control the pollution of the air, land and water, it is declared to be in the
public interest to establish minimum standards, rules and regulations for individual
sewage disposal systems in the County of Weld, and to provide the authority for the
administration and enforcement of such minimum standards, rules,and regulations.
B. Purpose. The purpose of these regulations,as authorized and required by Article 10
Title 25, C.R.S., is to provide guidance and establish minimum standards for the
location, construction, performance, installation, alteration and use of individual
sewage disposal systems,the transportation and final disposal of sewage materials
and the control of Systems Contractors and Systems Cleaners of such systems.
The Weld County Board of Public Health and the Weld County Board of County
Commissioners declares that the general purpose of these regulations is to require
the use of public sewer systems where and whenever feasible, and to limit the
installation of individual sewage disposal systems only to areas that are not feasible
for public sewers. This ordinance shall apply to all individual sewage disposal
systems and to sewage treatment works that are not required to comply with the
provisions of the Water Quality Control Act, Section 24-8-101, et seq., C.R.S. This
code meets or exceeds the requirements of the guidelines as adopted by the
Colorado Board of Public Health pursuant to Section 25-10-104, C.R.S., as
amended.
Sec. 30-1-20. Jurisdiction, Severability, Savings Clause.
A. These regulations are promulgated by the Weld County Board of County
Commissioners under the authority of the Weld County Home Rule Charter,
Section 3-8,acting as the Weld County Board of Public Health under authority of the
Weld County Home Rule Charter, and upon the recommendation of the advisory
Board of Public Health established pursuant to said Charter.
B. If any section of these regulations adopted hereunder or its application to any person
or circumstance is held invalid, unconstitutional, void or inoperative, such holding
shall affect other provisions or applications of the ordinance adopted hereunder. The
Board of Public Health and the Board of County Commissioners hereby declares
that in this regard, the ordinance adopted hereunder is severable, and that said
Boards would have adopted the remaining ordinance hereof notwithstanding such
holding.
C. The repeal of any regulation adopted hereunder shall not deny any right, action, or
cause of action, which arose under existing ordinances.
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D. The repeal and re-enactment of these regulations shall not prejudice the prosecution
of any violations under previous versions of these regulations.
E. The Board of County Commissioners hereby delegates these duties described
herein to the Board of Public Health subject to the rights of appeal as outlined in
these regulations.
F. Chapter Coverage:These regulations adopted by the Weld County Board of Public
Health,pursuant to current guidelines of the state board and adopted in compliance
with Section 25-10-104(2), (3), and (4) C.R.S., shall govern all aspects of permits,
performance, location, construction, alteration, installation, and use of individual
sewage disposal systems of less than 2,000 gallons per day design capacity. (Site
approval and a discharge permit from the Colorado Department of Public Health and
Environment are required for a system with design capacity greater than or equal to
2,000 gallons per day average flow. These regulations then govern all other aspects
of permits, performance, construction, alteration and installation.)
Sec. 30-1-30. Definitions.
The following definitions shall apply in the interpretation and enforcement of these
regulations. The word "shall," as used herein, indicates a mandatory requirement.
Absorption System: Waste water disposal field or a leaching field and adjacent soils or
other system for the treatment of sewage in an individual sewage disposal system by
means of absorption into the ground and may include evapotranspiration.
Absorption Trench: One or more trenches not over three feet in width,of varying length not
to exceed 100 feet, and not to exceed three (3) feet in depth, in which sewage effluent is
percolated into the soil.
Acceptable Design:A standardized design of tank, plant or system,the installation of which
is permitted by the Division, provided that site requirements are met.
Aerobic Sewage Treatment System: An individual sewage disposal system employing
biological action which is maintained by the addition of air or oxygen.
Applicant Any person who submits an application for a permit for an individual sewage
disposal system.
Approved: Official consent given in writing by the Division.
Bedrock: The more or less solid undisturbed rock in place either at the surface or beneath
surficial deposits of gravel, sand, or soil or a consolidated rock formation of impervious
material which may exhibit jointed, fractured, or deteriorated characteristics.
Board of Public Health: The Advisory Board of Public Health as designated by the Board of
County Commissioners pursuant to the Home Rule Charter.
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Building Sewer.That part of the piping of a drainage system which extends from the end of
the building drain and which receives the discharge of the building drain and conveys it to
a public sewer,private sewer, individual sewage disposal system,or other point of disposal.
Capillary Fringe:The uppermost level of groundwater travel through capillary action in the
soil.
Capillary Rise:The upward movement of groundwater in soil to the ground surface above
the underground water level or water table.
Cesspool: A covered underground receptacle which receives untreated sewage from a
building and permits the untreated sewage to seep into surrounding soil.
Cistern:A watertight covered receptacle of non-toxic materials which is designed for storage
of potable water.
Chapter. Chapter 30 of the Weld County Code also known as the Individual Sewage
Disposal System (ISDS) Regulations.
Composting Toilet A unit which consists of a toilet seat and cover over a riser which
connects to a compartment or a vault that contains or will receive composting materials
sufficient to reduce waste by aerobic decomposition.
Constructed Wetland: A system which utilizes various wetland plants to provide secondary
treatment of wastewater through biological, physical, and chemical processes.
Department: The Weld County Department of Public Health and Environment.
Design Flow:The design flow is one hundred fifty percent(150%)of average daily flow as
calculated by methods recognized in these regulations.
Dispersal System:A system for the disposal of effluent after final treatment in an individual
sewage disposal system by a method which does not depend upon or utilize the treatment
capability of the soil.
Distribution Box: A watertight chamber which receives waste water from a septic tank or
other primary treatment unit and from which effluent is distributed evenly throughout the
absorption system.
Division:The Division of Environmental Health Services,Weld County Department of Public
Health and Environment.
Division Representative:Also known as Environmental Health Specialist. A person who is
trained in the physical, biological, and/or sanitary science to carry out educational and
inspection duties in the field of environmental health.
Dosing: A high rate periodic discharge into an absorption system.
Dosing Tank:A tank which provides for storage of waste water from a septic tank intended
to be fed to an absorption area at a high rate periodic discharge.
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Drywell:A type of soil absorption system dependent upon suitable soil,filled with gravel and
containing a system of approved distribution which is designed on the basis of sidewall and
bottom absorption area. Drywells cannot be used for the disposal of toilet, bath, laundry or
kitchen wastes.
Effective Size: That size of granular media such that not more than ten percent (10%) by
weight of the media is finer than the size specified.
Effluent: The liquid waste discharge from an individual sewage disposal system.
Engineer. The Registered Professional Engineer for operative definition.
Environmental Health Specialist:Also known as Division Representative. A person who is
trained in physical,biological,and/or sanitary science to carry out educational and inspection
duties in the field of environmental health.
Evapotranspiration System:A type of dispersal system that wholly or primarily utilizes liquid
evaporation and transpiration by vegetation as a means of effluent disposal.
Experimental System:A particular design or type of system based upon improvements,or
development in the technology of sewage disposal and not otherwise provided for in
paragraphs (e) to (j) of Section 25-10-105(1), C.R.S.
Floodplain: An area adjacent to a stream which is subject to flooding as the result of the
occurrence of a one hundred (100) year flood, and is so adverse to past, current or
foreseeable construction or land use as to constitute a significant hazard to public or
environmental health and safety or to property or is designated by the Federal Emergency
Management Agency(FEMA)or National Flood Insurance Program(NFIP). In the absence
of FEMA/NFIP maps, a Colorado Registered Professional Engineer shall certify the
floodplain elevations.
Floodway: That area of the floodplain in which the channel of the watercourse and those
portions of the adjoining floodplain which must be reserved in order to discharge the base
flood without cumulatively increasing the water surface elevation more than one(1)foot at
any point or as designated by the Federal Emergency Management Agency or National
Flood Insurance Program. In the absence of FEMA/NFIP maps, a Colorado Registered
Professional Engineer shall certify the floodway elevation and location.
Geologist: See Professional Geologist for operative definition.
Grey Water System: A system designed to collect, treat and dispose only liquid wastes
from sinks, lavatories, tubs, showers, and laundry or other approved plumbing fixtures
excluding toilet fixtures.
Grease Trap: A unit designed to remove grease and fat from kitchen wastes.
Groundwater Table:The upper surface of groundwater in the zone of saturation of geologic
formation.
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Health Officer. The chief administrative and executive officer of the Weld County
Department of Public Health and Environment,or other representative as designated by the
Board of County Commissioners of Weld County.
Individual Sewage Disposal System and the Term "System"[(I.S.D.S.) Where the Context
so Indicates]:An absorption system of any size or flow,or a system or facility for collecting,
storing, treating, neutralizing, stabilizing, or disposing of sewage, which is not a part of or
connected to a sewage treatment works.
Lift Station:A device used for the vertical lifting of effluent to the required horizontal level of
either the absorption field or septic tank.
Limiting Zone:Any soil horizon in the soil profile or underlying strata which prevents the soil
from acting as an effective filter of organisms and suspended solids from effluent, and shall
include seasonal and perched water tables and the associated capillary fringe,determined
by direct observation or by observation of salts, chemically reduced iron expressed as
mottling or gleying; bedrock with impermeable, slowly permeable, or fractured strata; and
excessively coarse sand and/or gravel.
Liner.A watertight membrane liner of at least 0.01 inch (10 mil)thickness which is used to
prevent effluent from entering the soil or groundwater table. Material shall be polyvinyl
chloride or material of equal or greater integrity.
Manufacturer.The person or firm that constructs or assembles individual sewage treatment
system components.
Mound System: An absorption system installed where the top of the effluent distribution
pipe is installed above the original grade of the area used for absorption.
Owner. The person who is owner of record of the land on which an individual sewage
disposal system is to be designed, constructed, installed, altered, extended or used.
Percolation Tests:A subsurface soil test at the depth of a proposed absorption system or
similar component of an individual sewage disposal system to determine the water
absorption capability of the soil, the results of which are normally expressed as the rate at
which one inch of water is absorbed.
Permeability The property of a material which permits movement of water through the
material.
Permit A document, issued by the Division, authorizing the construction, alteration,
installation, repair, and use of an individual sewage disposal system.
Person: Individual,partnership,firm,corporation,association, or other legal entity and also
the state, any political subdivision thereof, or other governmental entity.
Plot Plan:An accurate drawing or map indicating the dimensions, acreage and location of
property lines, buildings, wells, individual sewage disposal systems, water courses,
geographical features and other pertinent information as required.
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Privy: A structure allowing for the disposal of excreta into a water-tight vault, and which
provides privacy and shelter and prevents access to the excreta by flies, rodents, or other
vectors.
Professional Geologist A person who is a graduate of an institution of higher education
which is accredited by a regional or national accrediting agency, with a minimum of thirty
semester(forty-five quarter) hours of undergraduate or graduate work in a field of geology
and whose post-baccalaureate training has been in the field of geology with a specific record
of an additional five years of geological experience to include no more than two years of
graduate work.
Registered Professional Engineer. An engineer licensed in the State of Colorado, in
accordance with Section 12-25-111, C.R.S.
Sand Filter.A subsurface system which utilizes wastewater filtration or absorption or both,
and which contains an intermediate layer of sand as filter material.
Seepage Bed or Absorption Bed: A subsurface soil absorption area which is wider than
three (3)feet, together with a system of approved distribution through which effluent may
seep, leach or infiltrate into the soil.
Seepage Pit: A type of soil absorption system dependent upon suitable soil containing a
structural internal void and designed on the basis of sidewall area.
Septage: The liquid and solid contents of a primary treatment facility.
Septic Tank: A watertight, accessible covered receptacle designed and constructed to
receive sewage from a building sewer, to settle solids from the liquid, to digest organic
matter,and store digested solids through a period of retention and allow the clarified liquids
to discharge to other treatment units for final disposal.
Serial Distribution:An arrangement of absorption trenches,seepage pits or seepage beds
where effluent is retained to utilize the absorption capacity of a component before flowing
into a succeeding component.
Sewage: A combination of liquid wastes which may include chemicals, house wastes,
human excreta,animal or vegetable matter in suspension or solution,and/or other solids in
suspension or solution and which is discharged from a dwelling, building,or other structure.
Sewage Treatment Works: A system or facility for treating, neutralizing, stabilizing, or
disposing of sewage,which system or facility has a designed capacity to receive more than
two thousand gallons of sewage per day, unless designed as an absorption system. The
term "sewage treatment works" includes appurtenances such as interceptors, collection
lines, outfall and the outlet sewers, pumping stations, and related equipment.
Site Evaluation:The testing of soils and examination of the location of a proposed I.S.D.S.
to determine the presence of, and limitations imposed by,the field percolation rate, limiting
zone(s), slope, and pertinent ground features; as performed by a Registered Professional
Engineer or Professional Geologist.
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Soil Horizon:A distinct layer of soil,gravel,cobbles or bedrock,separately or in combination,
approximately parallel to the soil surface with characteristics produced by soil-forming or
geologic processes.
Soil Profile: The accumulation of all soil horizons and bedrock, from the surface of the
ground to a depth of eight(8)feet or to bedrock, whichever is less, as exposed in a test pit
or boring log.
State Waters:Any and all surface and subsurface waters which are contained in or flow in
or through this state, except waters in sewage systems, waters in treatment works of
disposal systems, waters in potable water distribution systems, and all waters withdrawn
for use, until all uses and treatment have been completed.
Suitable Soil:A soil which will effectively treat and filter effluent by removal of organisms and
suspended solids before the effluent reaches any highly permeable earth such as joints in
bedrock, gravels, or very coarse soils and which meets percolation test requirements and
has a vertical thickness of at least four feet below the bottom of the absorption area.
Subsoil Drain:An underground drain which diverts percolated water away from a specified
area, such as with a French drain.
Systems Cleaner. A person engaged in and who holds himself out as a specialist in the
cleaning and pumping of sewage disposal systems and removal of the residues deposited
in the operation thereof.
Systems Contractor.A person engaged in and who holds himself out as a specialist in the
installation, renovation, and repair of sewage disposal systems.
Uniformity Coefficient A value which is the ratio of D60 to D10 where D60 is the soil
diameter of which 60%of the soil weight is finer and D10 is the corresponding value at 10%
finer. (A soil having a uniformity coefficient smaller than four would be considered"uniform"
for purposes of these regulations.)
Vault: A watertight, covered receptacle, which is designed to receive and store excreta or
wastes either from a sewer or from a privy and is accessible for the periodic removal of its
contents.
Wastewater Pond: A designed pond which receives exclusively wastewater from a first
stage treatment unit and which provides an additional degree of treatment.
Water Quality Control Commission:The Commission created by Section 25-8-201,C.R.S.
ARTICLE II
Administration and Enforcement
Sec. 30-2-10. General Sanitation Requirements.
A. The owner of any structure where people live,work, or congregate shall ensure that
the structure contains an adequate,convenient,sanitary toilet and sewage disposal
system in good working order. Under no condition shall sewage or effluent be
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permitted to be discharged upon the surface of the ground, or into Waters of the
State, unless the sewage or effluent meets the minimum requirements of these
regulations or the water quality standards of the Colorado Water Quality Control
Commission, whichever are applicable. Any person who is aware of a
malfunctioning septic system is encouraged to report the location of the system to
the Division.
1. All individual sewage disposal systems which are designed to utilize a
subsurface absorption system and which have been installed since July 1,
1973, shall be required to obtain a permit from this Division.
Sec. 30-2-20. Submission of Plans for Proposed Subdivisions.
Plans for proposed subdivisions shall be submitted to this Division for the review of proposed
individual sewage disposal systems by an Environmental Health Specialist or Registered
Professional Engineer in accordance with requirements of these regulations and the requirements
of the Weld County Planning Commission. The Division Representative or representative may
require the developer to submit additional engineering or geological reports or data and to conduct
a study of the economic feasibility of the sewage treatment works prior to making any
recommendation. No plans shall receive the approval of the Board of County Commissioners
unless the Division has made a favorable recommendation regarding the proposed method of
sewage disposal. Appeal from an unfavorable recommendation hereunder shall be in accordance
with the procedures outlined in these regulations.
Sec. 30-2-30. Existing I.S.D.S. Review.
In the case of an existing I.S.D.S., which was installed and exists without a permit, certain
circumstances, including but not limited to, a referral from the Department of Planning Services,
may require evaluation to assure compliance with Section 25-10-111(6), C.R.S. The owner of the
property shall certify in written form the size of the tank in gallons and the size of the absorption field
in square feet as it exists at the time of review. The Division Representative shall base their
evaluation for compliance on that submitted documentation.
Sec. 30-2-40. Permit Application Requirements and Procedures.
A. Prior to commencement of installation, alteration, or repair of a system, a written
application shall be submitted to the Weld County Department of Public Health and
Environment, Division of Environmental Health Services, providing,as a minimum,
the information called for on the application form and a permit shall have been
issued.
B. A permit fee,as set by the Board of Weld County Commissioners,shall be required
of applicants for the installation, alteration or repair of an individual sewage disposal
system, payable at the time the application is received. This fee shall be based on
the average cost to the Division for processing applications during the preceding
calendar year. Permit fees are non-refundable except as specifically provided in
Section 30-2-70.E. Permit applications are non-transferable. The issuance of a
permit does not denote approval of any zoning subdivision or building code
requirements.
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C. A permit fee,as set by the Board of Weld County Commissioners, shall be required
of applicants for any system that requires only a vault or holding tank with no
leaching area. An application for an Individual Sewage Disposal System permit must
be completed by the owner and a final inspection must be made by the Division
Representative with proper notice as specified in Section 30-2-50.D.
D. Any addition to a structure which will,or is likely to, result in increased sewage flow
to an existing system shall require approval by the Division and may require
expansion of the individual sewage disposal system or parts thereof.
E. The Weld County Board of Public Health and/or the Weld County Department of
Public Health and Environment, Division of Environmental Health Services, may
make provision for the waiver of any permit fee normally required for an individual
sewage disposal system.
F. If both a building permit and an individual sewage disposal system permit are issued
for the same property, and construction is not commenced prior to the expiration
date of the building permit,the individual sewage disposal system permit shall expire
at the same time as the building permit. If an individual sewage disposal system
permit is issued for property on which no building permit is required, the individual
sewage disposal system permit shall expire one year after the permit's issuance, if
construction is not commenced. Any change in plans or specifications after the
permit has been issued invalidates the permit unless written approval is secured
from the Division Representative for such changes. Expired permits can only be
renewed by payment of the permit fee and only if:
1. There has been no change in the plans and specifications of the proposed
system as set out in the original application;or such change is reviewed and
approved by a Division Representative.
2. The surrounding land and its use or zoning, have not changed so as to
cause the original application to be unacceptable or unsuitable under these
regulations.
G. The Weld County Division of Environmental Health Services may issue a repair
permit and an emergency use permit to the owner or occupant of property on which
a system is not functioning properly. Application for a repair permit shall be made
by such owner or occupant to the Division within two business days after receiving
notice that the system is not functioning in compliance with Article 10 of Title 25,
C.R.S.,or applicable sections of these regulations adopted thereunder or otherwise
constitutes a nuisance or a hazard to public health. The permit shall provide for a
reasonable period of time within which repairs shall be made. At the end of that
period the system shall be inspected by this Division to ensure it is functioning
properly. Concurrently with the issuance of a repair permit,the Division may issue
an emergency use permit authorizing continued use of a malfunctioning system on
an emergency basis for a period not to exceed the period stated in the repair permit.
Such an emergency use permit may be extended, for good cause shown, in the
event repairs may not be completed in the period stated in the repair permit through
no fault of the owner or occupant. A request for a variance from these regulations
may be made to the Division in accordance with Article IX.
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1. An individual sewage disposal system permit shall be required for expanded
use of an existing system.
2. The issuance of a permit and specifications of terms and conditions therein
shall not constitute assumption or create a presumption that the Division or
its employees may be liable for the failure of any system. The permit
issuance and associated terms also shall not act as a certification that the
equipment used in the system,or any component of said equipment used in
its operation, or that the system for which the permit was issued ensures
continuous compliance with the provision of Article 10 of Title 25,C.R.S.,the
rules and regulations adopted thereunder or any terms and conditions of a
permit.
3. Except as provided in these regulations, no individual sewage disposal
system permit shall be issued to any person when the subject dwelling,
place of business or institution is located within 400 feet from a sewer line of
a municipality or special district which provides public sewer service,except
where such sewer service to the structure is not feasible in the determination
of the municipality or special district.
Sec. 30-2-50. Lot Size.
Installation of an individual sewage disposal system shall be permitted only on building sites
which conform to the minimum setback requirements established in Appendix 30-B.
Sec. 30-2-60. Application Review.
A. Any person who wishes to install, alter, or repair an individual sewage disposal
system in Weld County, Colorado, shall first obtain, prior to commencement of
construction,a permit from the Environmental Health Services Division of the Weld
County Department of Public Health and Environment. The following minimum
information must be provided in the permit application:
1. Parcel Identification Number
2. Legal description of the property.
3. The property owner's name, mailing address and phone number.
4. The applicant's name, mailing address and telephone number.
5. Type of building by use.
6. Type of water supply.
7. Lot size, in acres.
8. Type of services required in the structure.
9. The owner's signature or agent with written permission to sign for the owner.
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10. Street or road address of the property, or directions to the site.
11. Such additional information as may be required by the Division.
12. Soil test data as required in Section 30-4-30.
B. After receiving an application for an individual sewage disposal system permit, the
application shall be reviewed by the Division and an inspection shall be made by the
Environmental Health Specialist consisting of:
1. Inspection of the premises, unless previously inspected;
2. An assessment of the general topographical conditions;
3. A preliminary assessment as to the suitability of the site and of the proposed
system design based upon verification of the groundwater table,suitable soil,
depth to bedrock,ground slope and pertinent physical features such as the
location of the disposal system with reference to wells, streams, lakes,
ditches, structures, and other geographical features;
4. A determination that the maximum usable portion of the lot that is used for
an individual sewage disposal system is no more than twenty-five (25)
percent unless a waiver has been obtained and approved by the Board of
Public Health for experimental or water conservation methods.
C. Additional Evaluation: When the Division Representative has determined that the
Division does not have sufficient information for evaluation of an application or a
system, he may require additional tests or documentation.
D. Additional Hydrological,Geological, Engineering or other Information: When specific
evidence suggests undesirable subsurface conditions exist,additional hydrological,
geological,engineering or other information provided by a Registered Professional
Engineer or geologist may be required to be submitted by the applicant. This
requirement shall not prejudice the right of the Division to develop its own information
from its own source(s).
E. Access to Site: For the purpose of inspection and enforcing applicable sections of
these regulations and the terms and conditions of any permit issued, the Division
Representative is authorized to enter upon private property at reasonable times and
upon reasonable notice for the purpose of determining whether or not operating
individual sewage disposal facilities and systems are functioning in compliance with
Article 10 of Title 25,C.R.S.,and applicable rules and regulations adopted pursuant
thereto and the terms and conditions of any permit issued and to inspect and
conduct tests in evaluating any permit application. The owner or occupant of every
property having an individual sewage disposal system shall permit the Division
Representative access to the property to conduct required tests, take samples,
monitor compliance, and make inspections. If access is denied, the Division
Representative may apply to the District Court for an order authorizing entry.
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Sec. 30-2-70. Determination.
A. A determination shall be made on behalf of the Division by an environmental health
specialist or a registered professional engineer after review of the application, site
inspection, test results, and other required information, whether the proposed
system is in compliance with the requirements of Article 10 of Title 25, C.R.S., and
applicable rules and regulations adopted under said section. A permit may be
issued by the Division Representative if the proposed system is determined to be in
compliance with the requirements of Article 10 of Title 25,C.R.S.,and the rules and
regulations adopted pursuant thereto.
B. After reviewing all required information,the Division may give conditional approval
for a permit for the proposed sewage disposal system, or it may recommend
disapproval of the application and denial of the permit if the proposed system cannot
be made to comply with these regulations. Written notice of the denial of a permit
or disapproval of plans shall be served upon the applicant as provided be the
Colorado Rules of Civil Procedure or by certified mail, return receipt requested.
Service by mail shall be complete upon receipt by the Division of the return receipt.
Any applicant whose permit application has been denied may request review of the
application by the Board of Public Health as provided in Section 30-9-20. The
conditional approval shall set forth conditions precedent to the issuance of a permit
including effluent testing, cleaning or maintenance schedules, or other special
conditions. No permit shall be issued to the applicant or to a subsequent owner until
the conditions have been met. Except as provided in 25-10-107,C.R.S., no permits
shall be issued for the following systems unless they are designed by a Registered
Professional Engineer and until they have been reviewed and approved by the Board
of Public Health:
1. Systems which service commercial,business,institutions,industry,or multi-
family dwellings.
2. Systems for single family dwellings whose locations cannot meet suitable
soil or slope requirements shall be designed by a Registered Professional
Engineer. If upon review by the Division Representative,the disposal field is
through an absorption system and the wastes are exclusively domestic type
wastes, approval may be made by the Division. A design may be required
to have Board of Public Health approval at the discretion of the Division.
3. Experimental systems.
C. Any system with a design capacity greater than or equal to 2,000 gallons per day
average flow will require a site approval and discharge permit from the Colorado
Department of Public Health and Environment. These code requirements then
govern all other aspects of permits, performance, construction, alteration, and
installation.
Sec. 30-2-80. Notification and Inspection Stages.
A. When construction of a sewage disposal system has been completed,the System
Contractor or owner shall notify the Division, and a representative of the Division
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shall make a final inspection within seventy-two (72) hours, or at an agreed time,
after receipt of notice, Saturdays, Sundays, and holidays excepted.
1. If upon final inspection of the system, the Environmental Health Specialist
finds the system installed in accordance with these regulations and the
permit,the Environmental Health Specialist shall issue final approval for the
completed system. If the system has been designed by or constructed
under the supervision of a Registered Professional Engineer, the Division
shall require the engineer to certify, in writing, to the Division that
construction and installation of the system has been completed in
accordance with the terms of the permit and these regulations. If the
inspection discloses any significant departure from the description or design
of the system as stated in the application and permit, or if any aspect of the
system fails to comply with these regulations, approval shall be withheld.
Written notice of deficiencies causing the disapproval shall be given to the
System Contractor or owner. A subsequent inspection shall be made upon
notification from the System Contractor or owner that the deficiencies have
been corrected and the system has been brought into compliance with these
regulations.
Sec. 30-2-90. Notice of Violations.
Whenever the Division Representative determines that there has been a violation of any
provision of these regulations,he/she shall give notice of such violation to the responsible person(s).
Such notice shall be in writing,shall specify the violation(s),provide a reasonable time for correction,
and shall be addressed to the owner of the property. Service of such notice shall be as provided
by the Colorado Rules of Civil Procedure or by certified mail, return receipt requested, deliverable
to addressee only. Service by certified mail shall be completed upon receipt by the Division of the
return receipt, or upon refusal to accept delivery by the addressee. If the property owner cannot
be found or served after a reasonable effort to do so by the Division, service may be made by
posting a notice in a conspicuous place on or about the property affected by the notice. A statement
by the Division Representative as to why the posting was necessary shall be included in the record.
Sec. 30-2-100. Prohibition of Individual Sewage Disposal Systems in Unsuitable Areas.
The Board of County Commissioners may conduct a public hearing, after written notice to
all affected property owners as shown in the records of the County Assessor and publication of
notice in a newspaper of general circulation at least ten days prior to the hearing, to consider the
prohibition of permits for individual sewage disposal systems in defined areas which contain or are
subdivided for a density of more than two dwelling units per acre. The Board of Public Health may
order such prohibition upon a finding that the construction and use of additional individual sewage
disposal systems in the defined area will constitute a hazard to the public health or the environment.
In such a hearing, the Board of Public Health may request affected property owners to submit
engineering and geological reports concerning the defined area and provide a study of the economic
feasibility of constructing a sewage treatment works. (Section 25-10-110, C.R.S.)
Sec. 30-1-110. Cease and Desist Orders.
The Health Officer or representative may issue an order to cease and desist from the use
of any system which is found by the Health Officer not to be functioning in compliance with Article
10 of Title 25, C.R.S., or with applicable rules and regulations or is found to constitute a nuisance
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or a hazard to public health, or has not otherwise received timely repairs under the provisions of
Section 25-10-106(i)(j), C.R.S. Such an order may be issued only after a hearing, which shall be
conducted by the Health Officer not less than 48 hours after written notice thereof is given to the
owner or occupant of the property on which the system is located, and at which the owner or
occupant may be present, with counsel, and be heard. The order shall require that the owner or
occupant bring the system into compliance or eliminate the nuisance or health hazard within a
reasonable period of time, not to exceed thirty days,or thereafter cease and desist from the use of
the system. A cease and desist order issued by the Health Officer shall be able to be reviewed in
the district court for the county wherein the system is located and upon a petition filed not later than
ten days after the order is issued.
Sec. 30-2-120. Re-Inspection Fee.
The Division may assess a re-inspection fee as established by the Board of County
Commissioners for each inspection or re-inspection when such portion of work for which inspection
is called is not complete or when corrections called for are not ready.
Sec. 30-2-130. Fee Refunds.
A. The Division may authorize the refunding of any fee paid which was erroneously paid
or collected. The Division may authorize the refunding of any fee paid when an
application for a permit for which a fee has been paid is withdrawn or canceled
before any work is done by the Division.
B. The Division shall not authorize the refunding of any fee paid except upon written
request filed by the original permittee.
ARTICLE III
Systems Contractor License
Sec. 30-3-10. General Requirements.
A. No person, except as in Section 30-3-10.B below, shall install, engage in the
installation of,or repair an individual sewage disposal system unless he holds a valid
Systems Contractor License. Employees of a validly licensed Systems Contractor
shall not be required to be licensed. The initial fee for a Systems Contractor License
shall be set by separate Chapter of the Board of Weld County Commissioners. A
license shall expire on December 31 of each year,and shall be renewed within thirty
(30) days prior thereto, and an annual renewal fee, as set by the Board of Weld
County Commissioners,shall be charged the fee established for new licenses upon
re-application.
B. Any owner of record shall be entitled to install one individual sewage disposal system
per year for his own private use under the terms and conditions of the permit. A
System Contractor license shall not be required for owner-installers who have
obtained permits in accordance with these regulations. However, owner-installers
shall be responsible for complying with all other applicable requirements of these
regulations, including but not limited to, assuring that all required inspections are
scheduled with, and performed by the Division Representative.
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Sec.30-3-20. Standard of performance required for holders of System Contractor Licenses.
A. Application for Systems Contractors License or renewals shall be made upon forms
supplied by the Division.
B. Prior to the issuance or renewal of a license, the Division Representative may
require the applicant to demonstrate adequate knowledge of these regulations.
C. Installation, renovation or repair of any individual sewage disposal system shall be
in compliance with these regulations and with the conditions set out in the installation
permit.
D. Notice of a requested inspection shall be given by the license holder not less than
twenty-four (24) hours before the inspection is to be made.
E. The license holder shall ensure that a permit has been issued before installation of
a system has begun.
Sec. 30-3-30. Revocation of License.
A. A license may be revoked for failure to comply with these regulations or for other
good cause shown above. Revocation shall take place only after a hearing before
the Board of Public Health. The license holder shall be given not less than ten(10)
days notice of the hearing and may be represented at the hearing by counsel.
B. Written notice of revocation explaining the violations shall be served upon the holder
of the Systems Contractor License. Service of notice as required in this Section
shall be as provided by the Colorado Rules of Civil Procedure, or by registered or
certified mail, return receipt requested, deliverable to the addressee only.
C. A person who has previously had a license revoked may be denied renewal of a
license by the Board of Public Health.
Sec. 30-3-40. Regulations of Systems Cleaners.
A. No person shall engage in the cleaning of sewage disposal systems or the
transportation of septage to a disposal site unless he holds a valid Systems Cleaner
License. Employees of a validly Licensed Systems Cleaner shall not be required to
be licensed. The initial fee for a Systems Cleaner License shall be as set by the
Board of Weld County Commissioners. Licenses shall expire on December 31 of
each year and an annual renewal fee, as set by the Board of Weld County
Commissioners, shall be charged. A license which lapses because of failure to
renew or is revoked shall be subject to the fee established for a new license upon
re-application.
B. Standard of Performance for Systems Cleaners.
1. A license holder,when cleaning a septic tank or aeration plant,shall remove
the liquid, solids, and scum, leaving no more than three (3) inches depth of
storage in a non-backflowing septic tank or aeration plant. In backflowing
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types of systems, cleaning shall be effective in reducing solids and scum to
the point of a near new system.
2. A license holder shall maintain his equipment so as to ensure that no spillage
of septage will occur during transportation, and that his employees are not
subjected to undue health hazards.
3. A licensed holder shall dispose of the collected septage only by the following
methods:
a. By disposal in a municipal sewage treatment collection system by
agreement and approval of the plant manager or responsible party.
b. By disposal at a site permitted and approved by the Weld County
Board of Public Health in accordance with Chapter 14 of the Weld
County Code pertaining to land application of septage, specifically
Section 14-7-100.
c. The Licensed Systems Cleaner shall provide the Division a list of the
locations and legal descriptions of all disposal sites utilized for each
load transported. This shall be provided monthly exceptforseptage
that is land applied. Septage which is land applied shall meet the
requirements of Section 14-7-100 of the Weld County Code.
d. Prior to the issuance of or renewal of a license, the Division
Representative may require the applicant to demonstrate adequate
knowledge of Sections 30-3-40.A and B.
C. Revocation of a Systems Cleaner License:
1. The procedures described in Section 30-3-30 shall be followed for the
revocation of a license.
ARTICLE IV
General Technical Requirements
Sec. 30-4-10. Calculation of Sewage Flow and Characteristics.
A. Where gallons per day and pounds of biochemical oxygen demand(BOD5)per day
can be obtained by measurement of existing conditions, such data may be used.
The Weld County Division of Environmental Health Services may require the
installation of a meter located to measure flow into the individual sewage disposal
system.
B. For new facilities Appendix 30-A, "Quantities and BOD Strength of Sewage for
Various Types of Uses" may be used as a guide to represent average conditions.
C. Maximum flow shall be considered as one hundred fifty percent(150%)of average
daily flow, and shall be the basis for design purposes unless otherwise established
by evidence satisfactory to the Division Representative.
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D. To calculate the sewage flow for dwellings and mobile homes, use a figure of two
persons per bedroom.
E. In no event may the system be designed for a lesser capacity than the anticipated
maximum daily sewage flow or treatment requirements of the sewage or wastes in
the system.
F. The Division Representative may,at his/her discretion,allow reduction in design flow
for proven, permanently installed water conservation devices. Reduction rates will
be based on flow rate information supplied to the Division for comparison with
standard accepted rates for each fixture that utilizes water conservation devices.
Total reductions may not exceed limits as provided in Section 30-5-30.C.
Sec. 30-4-20. Minimum Horizontal Setbacks.
A. Minimum,horizontal distances from the various components of a system to pertinent
terrain features, including streams, lakes, water courses, springs, wells, subsoil
drains, cisterns, water lines, suction lines, gulches, dwellings, other occupied
buildings and property lines, shall be in accordance with Appendix 30-B.
B. Wells,springs or potable water supply suction lines, and all other constructed units
listed in Appendix 30-B,shall be installed or located in accordance with the minimum
distance requirements provided in the table. The minimum horizontal distance
required from manmade cut banks and fill areas to individual sewage disposal
system components discharging effluent into or onto the surrounding soil shall be
four(4)times the height of the bank. The height shall be measured from the bottom
of the bank to the top edge of the bank, unless it can be demonstrated by a
Registered Professional Engineer or a Certified Professional Geologist that a
mechanical or natural barrier will prevent lateral effluent surfacing. See diagram
below.
4H Absorption
ITrench
/IH
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C. If minimum horizontal distances cannot be maintained to a well or property line as
a result of the construction of a replacement system,the property owner potentially
impacted by the affected setback must be notified ten (10)days prior to the Board
of Public Health hearing. The owner requesting the setback reduction must provide
to the Division the name(s) and address(es) of the affected property owners. The
Division will notify the neighboring property owners of the request,the hearing date,
time and place. The property owner requesting the setback may bring a written
statement of agreement of the reduced setback from the affected property owner(s)
in lieu of the Division notifying affected property owners.
Sec. 30-4-30. Soil Test
A. Location: Soil percolation tests shall be performed in at least six(6)test holes in the
area in which the absorption system is to be located, spaced uniformly over the
proposed site, except there shall be no less than one (1) test hole in any twelve
hundred (1,200)square-foot area of the absorption system. If an application is for
a system which does not utilize a soil absorption system, but employs a dispersal
system,the Division Representative may waive the requirement of percolation tests
upon request by the applicant. This request shall be supported by adequate subsoil
and bedrock reports and by a showing that the tests are not essential to the proper
design of the system and that the absence of test data will not endanger the public
health.
B. Dimensions:
1. The percolation test holes shall most preferably be six(6)inches in diameter.
The diameter may vary from four (4) to twelve (12) inches in width or
diameter where prohibitive soil orgeological conditions exist. The holes shall
be terminated at the depth of the proposed absorption system or to a depth
of at least thirty(30)inches. The percolation tests shall be conducted within
those soils comprising the four(4)feet of acceptable soils beneath bottom
of absorption field. The owner shall ensure that the soil percolation holes and
the boring or excavation shall be staked and identified and left open for
inspection,although the holes may be covered by boards or other temporary
cover for safety reasons.
2. The bottom and sides of the hole shall be scratched with a knife blade or
sharp pointed instrument,in order to remove any smeared soil surfaces and
to provide a natural soil interface into which water may percolate. All loose
material shall be removed from the hole. Two(2)inches of coarse sand or
fine gravel shall be added, or other suitable methods, such as sleeving to
protect the bottom from scouring and sediment.
C. Procedure:
1. Water used for the pre-soak and the percolation test shall be free of
petroleum products, oils and greases.
2. Percolation test holes shall be filled with water to a depth of fourteen (14)
inches or more at least eight (8) hours, but not more than twenty-four(24)
hours,prior to conducting the water percolation test,and shall be refilled with
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water if necessary to a depth of at least fourteen (14) inches prior to the
percolation test. The purpose of this procedure is to simulate the conditions
of an absorption area by giving the soil an opportunity to swell. Measure the
time for the water to drop one (1) inch within the lower six(6) inches of the
percolation test hole. The percolation rate shall be reported in minutes per
inch drop.
3. If water remains in a test hole after the overnight swelling period, its depth
shall be adjusted to approximately the lower twenty(20)percent depth of the
percolation test hole. The drop in water level shall be measured from a fixed
reference point over a thirty(30) minute period. This drop shall be used in
calculating the percolation rate for that hole.
4. If no water remains in a hole after the overnight swelling period, clear water
shall be added to bring the depth of water in the hole to approximately the
lower twenty (20) percent depth of the percolation test hole. The drop in
water level shall be measured from a fixed reference point at a minimum of
fifteen (15) minute intervals until two (2) consecutive, identical
measurements are obtained, or the majority of holes have stabilized. The
final measurement shall be used to calculate the percolation rate for that
hole.
5. In sandy soils (or other soils in which the first six (6) inches of water seep
away in less than thirty(30)minutes, after the overnight swelling period),the
water level shall be adjusted to approximately the lower twenty(20)percent
depth of the percolation test hole. The time between measurements shall be
taken as ten (10) minutes and the test run for one (1) hour or until the
majority of holes have stabilized. The drop that occurs during the final ten
(10) minutes is used to calculate the percolation rate.
6. In all cases water shall be added to the percolation test hole as required to
maintain a minimum depth of six (6) inches.
D. Calculation: The field percolation rate shall be the average rate of the percolation
tests after the majority of percolation test holes exhibit two(2)consecutive identical
measurements or the majority of holes have stabilized. A rate faster than five (5)
minutes per inch, or a rate slower than sixty(60)minutes per inch, shall render the
location unsuitable for an absorption system. However, sandy soils that percolate
faster than five(5)minutes per inch,but slower than three(3)minutes per inch, may
be allowed if they meet the requirements of Section 30-5-30.A.2.a. Sites with
unsuitable percolation rates shall require additional soil evaluation and design by a
Registered Professional Engineer if any absorption area is to be proposed. The field
percolation rate shall be used in calculating the absorption area required for the
proposed system. However,in no event shall the calculated absorption area be less
than that area required for systems with a percolation rate of five (5) minutes per
inch.
E. Performance of Percolation Tests:
1. The percolation test shall be performed by or under the supervision of a
Registered Professional Engineer,Certified Professional Geologist,or other
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similarly qualified professional, unless the tests were previously performed
by a Registered Professional Engineer and the results thereof submitted with
the application for a permit.
2. If the applicant demonstrates to the satisfaction of the Division
Representative that the system is not dependent upon soil absorption, the
requirement for percolation tests may be waived.
F. Alternate Percolation Test: Alternate percolation test or other soil test procedures
may be approved by the Division Representative when adequate and sufficient
scientific evidence shows the alternate procedures meet or exceed those
determined using the test procedure detailed in this Section.
G. Soil Profile: One soil profile pit shall be excavated to provide observation of the soil
profile of the area of the soil absorption system. A drill boring may be performed by
a Registered Professional Engineer or Professional Geologist, in lieu of a test pit.
The pit shall be prepared at least eight (8) feet deep. The pit may be terminated
when groundwater, bedrock or gravel is encountered. The pit shall be prepared so
as to provide identification of the soil profile four(4)feet below the bottom of the soil
absorption system.
1. The test pit shall have minimum horizontal dimensions of six(6)feet in width
and six (6) feet in length.
2. To allow entry and exit, at least one (1) wall of the test pit shall have a
maximum slope of forty-five (45)degrees from horizontal, or a ladder shall
be provided.
3. If in the opinion of the Division, the pit provided for observation appears to
have the potential for cave-in,the applicant must make appropriate changes
to the pit, as requested, to make it safe. These may include the following:
a. The excavation must have the sides sloped to an angle not steeper
than one and one-half (1-1/2) horizontal to one (1) vertical
(34 degrees measured from horizontal).
b. The excavation can be equipped with a trench box or shield that is
either designed or approved bya Registered Professional Engineer.
H. A suitable soil shall meet the following criteria:
1. A minimum depth of four (4) feet between the bottom of the proposed
absorption field and any limiting zone(s).
2. The capacity to adequately disperse the designed effluent loading as
determined by a field percolation rate of between five (5) minutes per inch
and sixty (60) minutes per inch, or by other approved soil tests.
3. Acts as an effective filter within its depth for the removal of pathogenic
organisms.
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Water Table: In the absence of more restrictive regulations of the Weld County
Board of Public Health, a test hole evaluation showing a dry condition estimated or
measured to be at least four(4)feet below the bottom of a proposed soil absorption
system during the months when seasonally fluctuating groundwater is at its highest,
may be considered prima facie evidence that the maximum seasonal groundwater
table will be sufficiently below the bottom of the proposed absorption system.
ARTICLE V
Component Design Criteria
Sec. 30-5-10. General Design Features.
A. Reliability: Individual sewage disposal systems shall be designed and constructed
such that each component shall function,when installed and operated,in a manner
not adversely affected by the normal operating conditions including erosion,vibration,
shock,climatic conditions,and usual household chemicals. Each component shall
be free of nonfunctional protrusions or sharp edges, or other hazards,which could
cause injury to persons, animals,or properties. Design shall be such as to exclude
flies and rodents and to prevent the creation of nuisances and public health hazards,
and shall provide for efficient operation and maintenance.
B. Pipe Standards: All wastewater lines used in individual sewage disposal systems
shall be constructed of compatible pipe, bonding agent, and fittings. Where plastic
pipe and fittings are used, the minimum wall thickness of the pipe shall conform to
Schedule 40,ASTM 3034,or SDR 35 PVC. Perforated distribution pipe surrounded
by rock within a soil absorption system shall have a minimum wall thickness
conforming to ASTM Standard 2729. Corrugated polyethylene pipe with smooth
interior that meets ASTM F405 and AASHTO M252 specifications or equivalent may
also be used.
C. Plumbing Codes: Plumbing fixtures, grease traps, building sewers, vents, sewer
lines and other appurtenances shall be designed,operated and maintained so as to
comply with the minimum requirements of the applicable and current Plumbing Code
or other local plumbing code in force on the date of the I.S.D.S. Permit Application.
D. Electrical Equipment, if used: All electrical work, equipment, and material shall
comply with the requirements of the current National Electrical Code in force on the
effective date of these regulations, or those revisions of said code as are adopted
by the State Electrical and Plumbing Board.
E. Identification and Data Marking: A permanent type plate or other indelible marking
so inscribed as to be easily read and visible for the purpose of inspection shall be
provided on major components not constructed on the site where installed. Said
inscription shall include the following:
1. Name of manufacturer.
2. Model or serial number designation.
3. Maximum design capacity of the unit and the unit of measurement.
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F. Structural Integrity: Tanks shall be so constructed and installed as to withstand
earth and hydrostatic pressures when full and when empty. The Colorado
Department of Public Health and Environment shall certify the structural integrity of
all tanks,treatment units,and piping materials for use in individual sewage disposal
systems. When the Colorado Department of Public Health and Environment is
satisfied and has issued certification,the Board of Public Health shall be entitled to
rely thereon.
G. Watertight Requirement: Watertight tanks, vaults, or other units, shall not allow
infiltration of groundwater or surface water and shall not permit the release of
wastewater or liquids through other than designed openings.
H. Tank Anchoring: In locations where groundwater may cause instability problems to
the septic tank, pumping chamber, vault, or other tanks in the individual sewage
disposal system due to flotation, the tank shall be anchored in a sufficient manner
in order to provide stability when the tank is empty. The method of anchoring must
be approved by the Division Representative prior to installation. The Division may
require the design of the anchoring system to be prepared by a Registered
Professional Engineer.
Accessibility for Inspection and Maintenance: Each treatment unit shall be equipped
with an access manhole located to permit periodic physical inspection, collection
and testing of samples and maintenance of all components and compartments
including but not limited to submerged bearings, moving parts,tubes, intakes,slots,
filters, inlet and outlet baffles, and other devices.
J. Indicators of Failure for Systems Utilizing Mechanical Apparatus: A signal device
shall be installed which will provide a recognizable indication or warning to the user
that the system or component is not operating or is operating but malfunctioning.
This indication or warning shall be in the form of a visual or audible signal, or both.
K. Serviceability: Components shall be so designed and constructed that when
installed in accordance with manufacturers'recommendations,they shall be capable
of being easily maintained, sampled, drained, pumped, inspected and cleaned.
L. Sampling Access: Where a required final effluent sample cannot be easily obtained,
a sampling well shall be constructed. The sampling well shall be accessible and
provided with a properly secured cover.
M. Instructions: The manufacturer shall provide clear,concise instructions covering the
unit which,when followed,will assure proper installation and safe and satisfactory
operation.
N. Surface Activity: The surface of the ground over the individual sewage disposal
system or any part thereof, must be restricted to activity or use which will allow the
system to function as designed, and which will not contribute to compaction of the
soil nor to structural loading detrimental to the capability of the component to function
as designed.
O. A distribution box shall be installed in all subsurface absorption systems, except
pressurized systems, and shall be of sufficient size to equally distribute effluent to
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the lateral lines and shall be constructed with the inlet invert at least one (1) inch
above the level of the outlet invert. Distribution boxes shall be installed level on
undisturbed soil,compacted soil,or on a concrete slab poured in place. For testing
purposes, an adequate amount of water shall be provided to check the level of the
inlet and outlet lines.
1. Distribution boxes shall have removable covers.
2. Each lateral shall be connected separately to the distribution box.
3. The distribution box shall be watertight and all pipes shall be grouted or
cemented. The box shall be located a minimum of five (5) feet from the
septic tank.
4. Outlet lines from the distribution box to the laterals shall be of solid wall pipe
for a minimum of five (5) feet.
5. In the event that treatment tank effluent is discharged to the distribution box
by a siphon or pump, a baffle shall be installed in the distribution box. The
baffle shall be secured to the bottom of the box,extending vertically to a point
level with the crown of the inlet pipe, and shall be perpendicular to the inlet.
In lieu of a baffle, the inlet pipe may have a ninety (90) degree bend which
diverts effluent downwards into the distribution box.
P. Lift Stations: If used,shall be equipped with audible and/or visual alarms as provided
in Section 30-5-10.J.
1. Non-clog pump opening shall have at least two (2) inch diameter solids
handling capacity where raw sewage is pumped or at least three-fourths
(3/4) inch diameter solids handling capacity if previously settled effluent is
pumped.
2. Automatic liquid level controls shall be provided to start and shut off pumps
at a frequency required by the design.
3. Pressure pipe shall be of sufficient strength to accommodate pump
discharge pressure and the pipe shall be sized to maintain a velocity of two
(2) or more feet per second.
4. Automatic air release valves shall be installed at high points in the pressure
line where necessary to prevent air locking.
5. Awatertightstorage basin housing the pump shall be provided to allow pump
cycling commensurate with the pump design capacity. The second
compartment of the septic tank shall not be used as a pumping chamber
unless the tank capacity is at least five hundred (500) gallons above the
minimum gallons required for the number of bedrooms. Additionally, the
pump must be screened or provided with an approved filtering device to
assure that only liquid effluent will be discharged.
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6. The discharge line from the pumping chamber shall be protected from
freezing by burying the pipe below frost level or sloping the pipe to allow it to
be self draining.
Sec. 30-5-20. Floodplains.
No new or expanded system shall be installed in a floodway. When a system is installed in
a one hundred (100) year floodplain, the new or repaired system shall meet or exceed the
requirements of the National Flood Insurance Program. The system as approved by the Division
Representative shall be designed to minimize or eliminate infiltration of flood waters into the system,
and discharge of the system into the flood waters.
A. If the tank lid is not above the one hundred (100)year floodplain elevation,then the
access to the tank manhole lids shall be covered with twenty (20) mil PVC and
sealed with plumbers cement or other appropriate sealer. When the seal is broken,
i.e., the tank is opened for pumping, etc., the tank shall be resealed prior to
backfilling.
B. A one-way valve shall be installed in the effluent line between the tank and the
absorption field.
C. All other requirements for installation of a septic system shall be met. For inspection
purposes,the materials to seal the manhole lids shall be on the site. The manholes
are not required to be sealed at the time of inspection in order to allow for the
inspection of tees' in the tank.
Sec. 30-5-30. Design Criteria (First Stage Treatment Units).
A. Grease Trap: Grease traps shall be provided in restaurants and similar
establishments where the quantity of grease and fats in liquid wastes is likely to be
large. Grease traps are not required in the average private home. Grease traps
shall be of the septic tank design,shall be installed between the building and septic
tank, and shall be located a maximum of thirty(30)feet from the plumbing fixtures
served to prevent congealing and clogging of waste lines. Grease traps shall be
designed and maintained so that liquid wastes leaving the unit will not cause
clogging of pipes or have a harmful effect on the bacterial and settling action in a
septic tank. The frequency of cleaning shall be determined at each establishment
during operation. However, the tank shall be required to be pumped when the
grease occupies one-half (1/2) of the liquid depth of the tank.
1. A grease trap shall be sized to permit a three(3)hour detention time, based
on the minimum required tank capacity.
2. The grease trap shall be a single compartment, septic tank type, with tight
fitting, removable covers for ease in cleaning. A silicon or rubber seal may
be necessary to ensure covers fit tightly to eliminate odors. Grease trap
covers shall be extended to the surface of finished grade to provide for
access for cleaning.
3. The inlet invert shall be at least three(3)inches higher than the outlet invert.
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4. The grease trap shall be provided with inlet and outlet tees. The inlet tee
shall extend at least six(6)inches below the liquid level. The outlet tee shall
extend to within six (6) inches but no closer than three (3) inches of the
bottom of the tank.
B. Septic Tank:
1. A septic tank shall be constructed to permit detention of incoming sewage
for a minimum of thirty(30) hours, or the capacity shall be based upon the
number of bedrooms according to Table 30-1.
Table 30-1
Septic Tank Size Based Upon Number of Bedrooms
Number of Bedrooms Tank Capacity(Gallons)
3 or less 1,000
4 1,250
each additional 250
a. For industrial, commercial, or institutional facilities, the minimum
capacity shall permit detention of incoming sewage for thirty (30)
hours at 150% of the estimated daily average flow, but in no case
shall there be less than 1,000 gallons capacity.
2. Prohibitions: Roof drains, foundation drains, area drains, or cistern
overflows shall not enter the tank or any part of the treatment system.
3. Septic tank design criteria:
a. The inlet invert shall be at least three(3)inches higher than the outlet
invert.
b. The inlet tee or baffle shall be provided to divert the incoming sewage
downward. The tee or baffle shall penetrate at least six (6) inches
below the liquid level, but not more than seventeen (17) inches.
c. The outlet tee or baffle shall extend above the surface of the liquid to
within one(1) inch of the underside of the tank top and shall extend
at least fourteen (14) inches below the outlet invert.
d. The distance from the outlet invert to the underside of the tank top
shall be at least ten (10) inches.
e. The liquid depth shall be a minimum of thirty (30) inches and the
maximum depth shall not exceed the tank length or sixty(60)inches,
whichever is less.
f. A septic tank shall have two(2)or more compartments or more than
one(1)tank may be used in series to provide the following capacity
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arrangement. The first compartment of a septic tank shall hold
one-half (1/2) to two-thirds (2/3) of the required effective capacity.
g. The transfer of liquid from the first compartment to the second or
successive compartment shall be made at a liquid depth of at least
fourteen (14) inches below the outlet invert, but not in the sludge
zone. A minimum four(4) inch diameter to a maximum six(6) inch
diameter sweep elbow pipe or aperture shall be placed in the partition
of the tank to accommodate the liquid transfer.
h. At least one(1)access, no less than twenty(20)inches across,shall
be provided in each compartment of a tank.
4. Installation of Septic Tanks:
a. Tanks shall be installed on a solid base and shall be level. The tank
shall be installed with removable covers or manholes. The inlet and
outlet covers or manholes shall extend to within eight(8) inches of
finished grade,with risers if necessary,in order to provide access to
each compartment for cleaning and inspection.
b. The building sewer to septic tank shall be laid with a minimum fall of
one-eighth(1/8)inch per foot(1/4 inch fall per foot is recommended).
Bends in the building sewer shall be limited to forty-five(45)degree
ells,or long-sweep quarter bends. The inlet and outlet pipes shall be
grouted and sealed with waterproof materials.
c. Backfilling around a septic tank shall be accomplished in a manner
to prevent settlement and to avoid undue strain on the tank and the
pipes entering and leaving the tank. A minimum of Schedule 40 PVC,
ASTM 3034,orSDR 35 shall be used for the building sewer and from
the septic tank to the head of the leach field and shall be laid with a
minimum fall of one-eighth (1/8) inch per foot.
d. All septic tanks and vaults shall be located and maintained in an area
which is accessible for the pumping of their contents.
Sec. 30-5-40. Design Criteria (Second or Later Stage Treatment Units).
A. Soil Absorption System (General):
1. For a system treating and disposing of effluent through a soil absorption
system,the method for calculating minimum absorption area shall be based
upon the amount of suitable soil and the capacity of the soil to absorb liquids
as established by the percolation test and upon design criteria and
construction standards for such type of absorption system as set forth in
these regulations.
2. Systems may not be permitted or installed in areas under the following
conditions unless they are designed by a Registered Professional Engineer
and approval of such systems has been obtained from the Board of Public
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Health. Approval may be given by the Division if authorized by the Board of
Public Health for such systems treating single family residential domestic
waste exclusively. A design may be required to have Board of Public Health
approval at the discretion of the Division.
a. Where the soil percolation rate is slower than one (1) inch in sixty
(60) minutes or faster than one (1) inch in five (5) minutes, except
that a percolation rate between one (1) inch in five (5) minutes and
one (1) inch in three (3) minutes in soils of uniform medium sandy
texture may be permitted by the Division, or the percolation may be
slowed by soil treatment.
b. Where the maximum seasonal level of the groundwater table is less
than four (4) feet below the bottom of the proposed absorption
system.
c. Where suitable soil exists less than four(4)feet below the bottom of
the proposed absorption system.
d. Where the ground exceeds slope requirements.
3. Soil building or replacement will be permitted to bring the soil within the
requirements of suitable soil, if designed by a Registered Professional
Engineer, and meets the requirements of Section 30-5-30.6.4.
4. Absorption Area Formulas:
a. The minimum trench absorption area in square feet (A) for an
individual sewage disposal system shall be determined as a function
of the estimated maximum design flow of sewage in gallons per
day(Q),and the percolation rate in minutes per inch(t),according to
the formula:
A trench = Q x it
3.5
b. Absorption bed area minimum shall be calculated at 1.3 times the
calculated absorption area required for absorption trenches,
according to the formula:
A bed = Q x it x 1 .3
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c. Where the percolation rate is found to be faster than five(5)minutes
per inch but not faster than three (3) minutes per inch in soils of
medium sandy texture, the minimum value of the "1' for use in this
formula shall not be less than "5".
d. Table 30-2, Subsurface Absorption Are for Dwelling Use, may also
be used for determination of the minimum absorption area required
per bedroom for a one(1)or two(2)family dwelling. If a percolation
rate falls between those designated in this chart, the next higher
percolation rate shall be used for sizing.
e. Where absorption systems are to be installed in new fill material,the
fill must be designed and/or tested by a Registered Professional
Engineer. In addition,the fill material shall consist of well-graded soil
with a percolation rate between ten (10) and thirty(30) minutes per
inch, no more than fifteen percent (15%) passing the #200 sieve,
free of heavy sod or other organic material,trash,frozen material or
debris. Placement of fill shall be deposited in layers not to exceed six
(6)inches in thickness,and each layer shall be compacted by means
of mechanical tampers, pneumatic rollers or other similar means.
The degree of compaction for fill shall range from 85% to 90% of
maximum dry density of ASTM D698 (standard proctor). Moisture
contents of fill material should range from three percent(3%)below
optimum to optimum moisture per ASTM 698. Compaction tests
shall be performed and the results thereof transmitted to the Division
Representative.
5. The bottom of the trench or bed and distribution lines shall be level.
6. The absorption field area shall be protected so as to prevent vehicular and
livestock traffic.
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Table 30-2
Subsurface Absorption Area for Dwelling Use
Trench Absorption Bed Absorption
Percolation Rate Area Per Area Per
Min/Inch Bedroom/Sq Ft Bedroom/Sq Ft
5 144 187
10 203 264
15 249 324
20 287 374
25 321 418
30 352 458
35 380 494
40 407 529
45 431 561
50 455 591
55 477 620
60 498 647
7. Allowable Absorption Area Reductions and Increases:
a. Flow reduction for the use of permanently installed water saving
devices may be allowed at the discretion of the Division
Representative,but in no case shall the maximum daily flow used for
design purposes allow greater than twenty percent(20%)reduction.
b. Reduction in soil absorption area may be allowed for gravel-less soil
absorption systems upon approval of the Colorado Department of
Public Health and Environment. In no case shall the maximum
reduction exceed fifty percent (50%) for trench or bed system.
c. The soil absorption area calculated as in Sections 30-5-30.B.1
through B.3 may be increased by an additional twenty percent(20%)
if wastes from a garbage grinder are discharged into the system and
by not more than an additional forty percent(40%)if wastes from an
automatic clothes washing machine are discharged into the system.
d. If dosing is used in conjunction with an absorption trench or seepage
bed system, a reduction of twenty-five percent (25%) may be
allowed.
e. The maximum reduction from all combined alternatives shall be no
greater than fifty percent (50%) of the standard required soil
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absorption area and shall be subject to the limitation contained in
Section 30-5-30.C.3.
8. The ground surface shall be graded to deflect precipitation or other outside
water from the disposal area. The absorption area shall be protected against
erosion and protected from vehicular and livestock traffic.
9. Alternating Systems: A diversion valve or other approved diversion
mechanism may be installed on the septic tank effluent line allowing
alternating soil absorption systems. Each soil absorption system shall be a
minimum of fifty percent (50%) of the total area required excluding the
reductions given for dosing and gravelless systems. The diversion
mechanism shall be readily accessible from the finished grade and shall be
switched on an annual basis. Additional reductions in absorption field area
over and above flow reductions as specified in Section 30-5-30.C, may not
be taken for alternating systems.
10. Dosing: Dosing may be used in conjunction with soil absorption systems.
For systems which utilize dosing, the system shall be designed by a
Registered Professional Engineer. The dosing frequency may be calculated
according to Table 30-3.
Table 30-3
Suggested Dosing Frequencies for Various Soil Textures
Soil Texture Dosing Frequency
Sand 4 doses/day
Sandy Loam 1 dose/day
Loam Frequency not critical*
Silty Loam 1 dose/day*
Silty Clay Loam 1 dose/day*
Clay Frequency not critical*
*Long term resting provided by alternating fields is
desirable and recommended in these soils
B. Absorption Trench Construction.
1. At least two trenches of near equal length shall be constructed with a length
not to exceed one hundred (100)feet, a width not exceeding three(3)feet,
and a depth not exceeding three (3) feet to the bottom of the excavated
trench from existing ground level at the Site Evaluation.Only one(1)trench
will be required if the system's required total area does not exceed two
hundred (200) square feet. There shall be a minimum (horizontal
measurement) of six (6) feet of undisturbed earth between adjacent
trenches. Any dimensional change from these specifications requires
approval from the Division Representative. A disposal line shall be provided
for each trench and shall be surrounded by clean,washed,graded gravel or
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rock or similar aggregate. The material may range in size from three-fourths
(3/4) inch to two and a half(2-1/2) inches with an average size of one and a
half(1-1/2)inches. The material shall extend from two(2)inches above the
top of the pipe, level across the trench,to six(6)inches below the bottom of
the pipe. The top of the gravel shall be covered with untreated building paper,
a two(2) inch layer of straw or hay, or a similar pervious material to prevent
the gravel from becoming clogged by earth backfill. An impervious covering
shall not be used, as this interferes with evapotranspiration at the surface.
After final inspection and approval there shall be at least twelve(12)inches
and not more than twenty-four (24) inches of backfill soil, suitable for
vegetation, placed over the trench,which shall be graded to promote runoff
water from the disposal area. No trees or shrubs shall be placed closer than
six(6)feet to the trench. The bottom of the trench shall be excavated level.
A four (4) foot depth of suitable soil below the bottom of the trench is
required. Machine tamping, rolling or hydraulic compaction of final cover
shall not be permitted, however, hand tamping may be allowed where
necessary to stabilize the soil to prevent erosion or the intrusion of
extraneous water. A distribution box shall be included in the absorption
trench system,except a one trench system,and shall meet requirements of
Section 30-5-10.0. Trenches shall follow the ground contour surface so that
variations in trench depth shall be minimized.
2. Perforated plastic distribution lines shall meet the requirements of
Section 30-5-10.6. Pipe diameter of three (3) or four (4) inches shall be
fitted with tight joints and the perforations shall be laid such that an even
distribution of effluent over the trench system will occur. (Note: Each
perforated pipe segment shall be so placed that effluent will be equally
dispersed downward into the gravel from each row of perforations per
segment). Tile or open joint pipe shall not be used.
3. For slopes between fifteen percent (15%) and twenty-five percent (25%),
absorption trench systems must be designed by a Registered Professional
Engineer,who shall provide a detailed engineering design in relationship to
elevation, and shall inspect and approve construction of the system. The
Board of Public Health shall review and consider such plans for approval.
Absorption trenches on slopes in excess of twenty-five percent(25%)are not
permitted.
4. If dosing is used in conjunction with an absorption trench system,the dosing
chamber shall be sized to account for the volume of the distribution system
and the dosing frequency.
5. For systems using gravelless absorption technology,the references to rock
and pipe depth and impervious material covering shall be omitted. All other
installation requirements(i.e. distribution box,five(5)foot solid pipe, depth
restrictions, etc.) shall be adhered to.
C. Absorption Bed Construction:
1. Absorption beds shall be constructed with a length not to exceed one
hundred (100) feet, a width greater than three (3) feet, and a depth not
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exceeding three (3) feet to the bottom of the excavated bed, from existing
ground level at the Site Evaluation. Any dimensional change from these
specifications requires approval from the Division Representative. The bed
area shall be covered evenly with a twelve(12)inch depth of clean,washed,
graded gravel or rock or similar aggregate. The material may range in size
from three-fourths(3/4)inch to two and a half(2-1/2)inches with an average
size of one and a half(1-1/2)inches. The material shall extend from two(2)
inches above the top of the pipe,level across the bed,to six(6)inches below
the bottom of the pipe. The top of the gravel shall be covered with untreated
building paper, a two (2) inch layer of straw or hay, or a similar pervious
material to prevent the gravel from becoming clogged by earth backfill. An
impervious covering shall not be used, as this interferes with
evapotranspiration at the surface.Aftera final inspection and approval there
shall be at least twelve(12)inches and not more than twenty-four(24)inches
of backfill soil, suitable for vegetation, placed over the bed, which shall be
graded to promote runoff water from the disposal area. In the case of an
above ground system, such as a mounded system, an impervious berm,or
liner of at least ten(10)mil thickness shall be constructed to prevent lateral
flow of waste discharge outside the absorption field,unless specified by the
design engineer. No trees or shrubs shall be placed closer than six(6)feet
to the bed. The bottom of the bed shall be excavated level. A four(4) foot
depth of suitable soil below the bottom of the bed is required. Machine
tamping,rolling or hydraulic compaction of final cover shall not be permitted,
however,hand tamping may be allowed where necessary to stabilize the soil
to prevent erosion or the intrusion of extraneous water. If the bed area
exceeds two thousand (2,000) square feet the bed may be installed in a
minimum of two (2) sections with either an alternating valve or alternating
dosing siphon,or distributed simultaneously and evenly among all sections.
2. The outermost dispersal lines in the bed shall be placed no less than
eighteen(18)inches and no more than thirty-six(36)inches from the outside
bed walls. Disposal lines shall be placed six (6) feet on center across the
width of the bed and extended the length of the bed. Such lines shall be
placed to distribute the effluent evenly across the entire bed area and shall
meet the requirements of Section 30-5-30.G. A distribution box shall be
included in the absorption bed system, and shall meet the requirements of
Section 30-5-10.0.
3. The maximum slope on which an absorption bed is permitted is eight percent
(8%).
4. If dosing is used in conjunction with an absorption bed system, the dosing
chamber shall be sized to account for the volume of the distribution system
and the dosing frequency.
5. All effort shall be made to excavate the field so that wheeled traffic is
minimized on the absorption surface to prevent compaction and impede
percolation.
6. For systems using gravelless absorption technology,the references to rock
and pipe depth and impervious material covering shall be omitted. All other
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installation requirements(i.e. distribution box, five(5)foot solid pipe,depth
restrictions, etc.) shall be adhered to.
D. Evapotranspiration Disposal of Effluent. An evapotranspiration system may be used
exclusively or in combination with a soil absorption system.
1. An evapotranspiration system shall be designed by a Registered
Professional Engineer who shall furnish design data for a complete review
of the design.
2. Data to be furnished shall include, but shall not be limited to: liner material
and bedding, properties of the soil in the evapotranspiration bed, and
provision for vegetation cover.
3. When high groundwater table, bedrock, fractured rock, or highly pervious
material(percolation faster than five(5)minutes per one(1)inch)endanger
the underground water,a durable and impermeable liner shall be installed to
prevent the sewage effluent from entering the underlying formation or
groundwater table. Liners shall be impervious to the chemical reaction and
passage of sewage. Polyvinyl chloride plastic lining, manufactured from
domestic polyvinyl chloride resin,of 10 mills thickness;butyl rubber,or other
non-toxic equivalent materials,shall be used. The liner shall be sealed of all
openings to the bed and shall completely underlie the matrix of the
evapotranspiration bed. Seams shall be bonded tightly and imperviously.
Any damage to the liner shall be repaired using the proper solvent or mastic
and patch of the same material as the liner. Liners shall not be laid directly
on any sharp rocks or objects. A sufficient amount of sand or fill material
shall be added over sharp bedrock to prevent the puncturing of the liner.
Construction shall be of sufficient quality as to maintain the integrity of the
liner to its specifications.
4. An evapotranspiration system shall be located in an area where there is
exposure to sunshine.
5. The system bed shall be crowned and covered with a minimum of four(4)
inches of selected backfill material and with a vegetation cover.
6. Bed area shall be protected to prevent damage from vehicular, livestock,or
pedestrian travel. Heavy machinery shall not be permitted to drive over the
matrix or the liner. The ground surface shall be graded to deflect
precipitation and other outside water away from the disposal area.
7. The following formula shall be used as a guide for determining the area
necessary for total evapotranspiration of septic tank effluent:
Area (in square feet) = Maximum Design Flow (gallons per day) x 586
Lake Evaporation Rate at the Site (inches per year)
8. As an alternative,a system may be designed on the basis of a monthly water
balance for the system. Such a design would provide for total storage of
average daily flows for all periods in which evapotranspiration is not shown
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to occur. The design shall also provide wicks (sand structures which
penetrate through the rock media to the bottom of the bed) equal to ten
percent(10%) to fifteen percent(15%) of the bed surface area. The wicks
shall be uniformly spaced throughout the bed. Adequate surface area shall
be provided to evaporate/transpirate total annual average daily flows at a rate
equivalent to local net lake evaporation over the remaining period of the year.
(If the system is designed as a percolation/evapotranspiration system, the
amount of storage and ET capacities may be reduced by the volume of
effluent percolating into the soil.) Precipitation and Evaporation field sizes
shall be calculated at the following minimum rates:
Table 30-4
Precipitation and Evaporation Field Sizes
Precipitation Evapotranspiration
13.97 inches/year 32.87 inches/year
9. Allowable absorption shall be calculated at the following maximum rates:
Table 30-5
Allowable Absorption
Percolation Rate GPD/SF
61 -90 MPI .20
91 •. 120 MPI .15
121 + .10
10. Sand utilized in Evapotranspiration or Evapotranspiration/Absorption beds for
cover shall meet the following gradation requirements and be approved by
the design engineer:
Table 30-6
Gradation R guirements
Sieve Size Percent(%) Passing
4 100
40 50 - 55%
200 < 15
E. Evapotranspiration/Absorption Bed: Combination systems shall be designed by a
Registered Professional Engineer. A distribution box meeting the requirements of
Section 30-5-10.0 shall be included in the system and distribution lines in such
systems shall meet the requirements of Section 30-5-30.G.2. Excavation shall not
occur when soils are wet.
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1. Calculations submitted for the rate of effluent disposal shall include both the
anticipated absorption rate and the anticipated evapotranspiration rate. For
percolation rates greater than sixty(60)minutes per inch, but less than one
hundred twenty(12O)minutes per inch,calculate the ratio of sixty(60)to the
actual percolation at the site. The resulting ratio is the percentage of the
maximum daily flow(Qmax) to be used in the formula for absorption. The
remainder of the maximum daily flow shall be used in the formula for
evapotranspiration systems. The percolation rate reported shall be used in
the absorption formula.
Example: Qmax = 675 gallons per day
Percolation rate = 80 minutes per inch
60 = .75
80
Thus 75% of 675 gallons per day is used in the absorption formula
with the reported perc rate for the site; and 25% of 675 gallons per
day is used in the formula for evapotranspiration systems.
2. The areas determined to be required for absorption and evapotranspiration
shall be added to determine the total area required.
F. Sand Filter: A sand filter system shall be designed by a Registered Professional
Engineer who shall furnish design data for a complete review of the design.
1. The filtering material shall be clean,coarse sand,all passing a screen having
four meshes to the inch. The sand shall have an effective size between 0.25
and 0.6 mm. The uniformity coefficient shall be 4.0 or less.
2. The sand shall be at least two(2)feet deep below the distribution lines. The
distributors and under drain shall be surrounded by coarse screened gravel
or crushed stone. Under drain effluent must then be discharged via a soil
absorption system.
a. All of the gravel or stone shall pass a two and one-half(2-1/2) inch
screen and shall be retained on a three-fourths (3/4) inch screen.
Fine gravel one-fourth(1/4)inch size or less may be used above and
around the coarse material, both at the distributor and under drains.
The separating distance between parallel distribution lines shall not
exceed six(6)feet,and a distribution line shall be located within three
(3)feet of each filter sidewall but no closer than eighteen(18)inches.
Pipe for gravity distribution shall be no less than four (4) inches in
diameter. The slope of the distributors shall be 0.4 percent where
dosing tanks are not used, and the slope of the under drains 0.5 to
1.0 percent. The sand must be thoroughly settled by flooding or other
means before the distributors are placed at the final grade. The
distributor and under drains shall meet the requirements of perforated
pipe as outlined in Section 3O-5-30.G.2.
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b. The top of the sand bed shall be no less than four(4)feet above the
high groundwater table for installations in which effluent percolates
downward through the soil.
3. The minimum area for a sand filter shall be computed as a function of the
maximum daily sewage flow according to Table 30-7.
Table 30-7
Loading Rates for a Sand Filer
Application Rate
Type of Service Gallons/Sq. Ft./Day
Without garbage grinder 1.15
With garbage grinder 0.95
4. A tank with a dosing pump or dosing siphon shall be provided where the total
filter area exceeds one thousand eight hundred(1,800)square feet. The size
of the dose, or the net capacity of the dosing tank, shall be at least
seventy-five percent (75%) of the volume of the distributors.
G. Mound Systems: A mound soil absorption system shall be designed by a
Registered Professional Engineer. The design shall be site-specific and include
specifications for fill material, basal area size calculations, absorption area
calculations, distribution networks, vertical liner, if necessary, cap, topsoil, final
grading,and other pertinent information to the construction of the system as may be
requested by the Division Representative.
1. The distribution system shall be designed for uniform effluent application
throughout the mound.
2. The effluent distribution system shall be graded to drain back to the dosing
chamber or buried below frost line.
3. The final slope of the mound backfill shall be no greater than 3 to 1 (three[3]
feet horizontally to one [1] foot vertically).
4. The mound shall be planted with suitable vegetative cover.
H. Gravel-less Soil Absorption System: All gravel-less soil absorption systems shall
be approved by the Colorado Department of Public Health and Environment. These
systems shall be limited to only those absorption area reductions given through the
Colorado Department of Public Health and Environment's certification. The
absorption area of a chamber type absorption system shall be equivalent to the
footprint of the interior of the chamber (Interior base area).
Constructed Wetland Treatment:A constructed wetland treatment system shall be
designed by a Registered Professional Engineer and the design shall be site specific
and include specifications for: loading,capacity, liner material,filter media,density
and species of plant material, effluent level, final discharge type, instructions for
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maintenance and other pertinent information as requested by the Division
Representative. Only subsurface flow systems will be permitted for installation.
1. The constructed wetland cell shall provide a retention time of at least three
(3) days and shall be designed so that the effluent does not surface. The
length, width and depth of the cell, and the means of effluent distribution
throughout the cell must be specified. The maximum depth of the wetland
cell shall not exceed three (3) feet.
2. The liner shall have a thickness of at least twenty-five (25) mil or its
equivalent.
3. A level control structure that allows for the altering of water level or complete
drainage of effluent from the wetland shall be installed in each cell.
4. If the effluent exiting the wetland treatment cell is disposed of in an absorption
field,there must be four(4)feet of suitable soil below the bottom of the field.
5. An adequate area on the property shall be required for the installation of a
full-sized absorption area in the event the constructed wetland malfunctions
or does not provide the higher quality effluent.
6. The design shall include estimates of effluent quality at the inlet and outlet.
Sampling ports, or another means of effluent sampling, to demonstrate
compliance with Section 30-6-10 of these regulations, shall be required by
the Division. Any sampling required as a part of the permit approval is to be
paid for by the owner.
J. Drip-Irrigation or Low Pressure Pipe:All drip-irrigation or low pressure pipe systems
may be allowed by the Division provided the system is designed by a Registered
Professional Engineer and the design data includes specifications for: dosing,
provisions for vegetative cover,cleaning of the manifold and distribution laterals,and
instructions for maintenance.
1. Trenching shall not occur when soils are wet.
2. Trench depth shall not exceed thirty(30)inches, and trench length shall not
exceed one hundred (100)feet. Trench bottom shall be level, plus or minus
one and one-half(1-1/2) inches.
3. No irrigation shall be allowed over the disposal area.
4. The system shall only be utilized when a four (4) foot separation can be
obtained between the bottom of the trench and fractured bedrock and/or
seasonally high water table.
5. Systems shall not be located upgradient from structures unless the design
engineer makes a determination and certifies in writing to the Division that it
is his/her professional opinion that effluent from the system will not enter
foundation drains and/or will not have any structural impact on the building.
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Sec. 30-5-50. Additional Design Criteria (Other Facilities).
A. Grey water system: A grey water system shall be considered when a separate
system is provided to dispose of human excreta. The standard design requirements
for conventional individual sewage disposal systems prescribed in these regulations
shall apply to grey water systems except that:
1. The design shall be based on a minimum volume of wastes of fifty (50)
gallons per person, per day, exclusive of toilet wastes;
2. A minimum of thirty(30)hours retention time shall be provided for each grey
water treatment tank; and
3. The building drain and sewer leading to the grey water treatment tank shall
be a maximum of two(2) inches diameter to preclude a later tap for a toilet.
B. Vault: A vault,shall have a minimum one thousand(1,000)gallon effective capacity,
and may be permitted under limited use occupancy for water carriage sewage
systems on property which cannot accommodate a sewage treatment system.
Vaults shall meet the same installation and construction requirements as apply to
septic tanks, except that no effluent outlet shall be provided. A signal device shall
be installed to indicate when pumping is necessary.
C. Vault Privy: A vault privy shall be built to include fly-tight construction, a
superstructure affording complete privacy, an earth mound around the top of the
vault and below floor level which slopes downward away from the superstructure
base, a floor and riser of concrete or other impervious material, and seats with
hinged covers of easily cleanable, impervious material. All venting shall be
fly-proofed with No. 16 or tighter mesh screening. Effective capacity of the vault
shall be no less than one thousand (1,000) gallons.
D. Incineration and Chemical Toilets: An incineration toilet, which may be used in
connection with a grey water system by permit from the Board of Public Health,shall
be designed and installed in accordance with all applicable federal,state,and local
air-pollution requirements. A portable chemical toilet,which may be used by permit
from the Board of Public Health, shall have a superstructure which meets the
requirements of Section 30-5-40.C. Use of a portable chemical toilet in permanently
occupied buildings shall be prohibited except during construction or under
emergency circumstances as determined by the Division.
E. Business, Commercial, Industrial, Institutional or Multi-family Dwelling Waste
Systems:
1. Performance criteria and construction standards for a system which will
service commercial, business, institutional or industrial property, or multi-
family dwellings shall conform to these regulations.
2. Such systems shall be designed by a Registered Professional Engineer. An
application for such a system shall be reviewed and approved by the Board
of Public Health
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3. Systems shall receive only such biodegradable wastes for treatment and
disposal as are compatible with those biological treatment processes as
occur within the septic tank and the soil matrix.
F. Composting Toilets:
1. Deposits of feces,urine,and readily decomposable household garbage that
is not diluted with water or other fluids may be retained in a compartment, in
which aerobic composting will occur. The compartment may be located,
subject to the Board of Public Health, or other applicable regulations or
codes, within a dwelling or building provided the unit complies with the
applicable requirements of these regulations,and provided the installation will
not result in conditions considered a health or nuisance hazard as
determined by the Division. The effective volume of the receptacle must be
sufficient to accommodate the number of persons served.
2. Adequate additional volume shall be provided for the use of composting
materials which shall not be toxic to the process or hazardous to persons,
and shall be used in sufficient quantity to assure proper decomposition.
3. Compartment and appurtenances related to the unit shall include fly-tight
construction and exterior ventilation as required by the plumbing code.
4. When the available effective volume is filled to seventy-five percent(75%)of
capacity, residue from the unit shall be properly disposed of by acceptable
solid waste practices.
5. If a system will be installed where low temperature may be a factor, the
design shall compensate for the effects of the low temperature.
6. Composting toilets shall bear the seal of approval of the National Sanitation
Foundation or an equivalent testing program. Composting toilets shall be
operated according to manufacturers' specifications.
G. Systems for which data on design,operation and maintenance, based upon use in
Colorado, are limited or undetermined:
1. Systems which recycle treated wastewater for non-potable purposes such
as flushing water closets or urinals:
a. That portion of the wastewater recycled for non-potable purposes,
such as flushing water closets or urinals, must meet the treatment
requirements of Section 30-6-10 of these regulations for effluent in
which the possibility exists for occasional direct human contact.
b. No cross-connection to a pipe, fixture, or supply containing potable
water shall be permitted.
c. Systems which recycle treated wastewater for potable purposes:
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1) No system shall be permitted which will recycle wastewater
for potable purposes except a system which shall
consistently meet all of the sanitation and maximum
contaminant level requirements of rules, regulations and
standards of the Colorado Department of Public Health and
Environment and of the Board of Public Health.
H. Prohibitions: Cesspools, flush hopper toilets, wastewater ponds for primary
treatment of human sewage and any other systems not delineated in these
regulations are prohibited, except where provided by Section 30-6-30.
ARTICLE VI
Other Treatment Systems
Sec.30-6-10. Treatment Systems Other than those Discharging Through a Soil Absorption
or Sand Filter System and Non-Discharging Systems.
A. Those systems which will discharge effluent directly to the atmosphere,the ground
surface or below ground, or which employ aerobic principles of sewage treatment
or a dispersal system, may be permitted only if designed by a Registered
Professional Engineer. This Section shall not apply to systems discharging below
ground through a soil absorption system or sand filter system or to a
non-discharging system.
B. The Board of Public Health shall review all applications for such systems which may
result in discharge or drainage of effluent from the property of origin. No permit shall
be issued for such a system if the Board of Public Health determines a potential
health hazard or private or public nuisance or undue risk of contamination exists.
The Board of Public Health, may, by regulation, authorize the Division to review
applications and issue permits for systems which do not permit the drainage of
effluent off the property of origin. For systems discharging to State Waters, see
Section 30-6-40.
C. The following minimum performance criteria shall be required for all systems
pursuant to this Section 30-6-10.
1. If effluent discharge is made into the atmosphere or upon the ground surface
in areas in which the possibility exists for occasional direct human contact
with the effluent discharge, the effluent at the point of sampling shall meet
each of the following standards:
a. The geometric mean of the fecal coliform density shall not exceed
twenty-five(25)per one hundred(100)milliliters when averaged over
any five (5) consecutive samples, and no single sample result for
fecal coliform shall exceed two hundred(200)per one hundred(100)
milliliters.
b. The arithmetic mean of the standard five(5)day biochemical oxygen
demand (BOD5) shall not exceed twenty (20) milligrams per liter
when averaged over any three consecutive samples.
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c. The arithmetic mean of the total suspended solids shall not exceed
forty (40) milligrams per liter when averaged over any three
consecutive samples.
2. If the effluent discharge is made into the atmosphere or upon the ground
surface in an area so restricted as to protect against the likelihood of direct
human contact with the discharged effluent, the effluent at the point of
sampling shall meet each of the following standards:
a. The geometric mean of the fecal coliform density shall not exceed
five hundred (500) per one hundred (100)milliliters when averaged
over any five (5) consecutive samples, and no single sample shall
exceed five thousand (5,000)fecal coliform per one hundred (100)
milliliters.
b. The arithmetic mean of the standard five(5)day biochemical oxygen
demand (BOD5) shall not exceed twenty (20) milligrams per liter
when averaged over any three consecutive samples.
c. The arithmetic mean of the total suspended solids shall not exceed
forty (40) milligrams per liter when averaged over any three
consecutive samples.
3. If effluent discharge is made beneath the surface of the ground and
discharge will not be made through suitable soil, either existing or
constructed, or through a sand filter, the following standard shall be met:
a. There shall be at least (4) feet of soil between the maximum
seasonal high water table and the level of effluent discharge.
b. The arithmetic mean of the standard five(5)day biochemical oxygen
demand(BOD5)shall not exceed sixty(60)milligrams per liter when
averaged over any three consecutive samples.
c. The arithmetic mean of the total suspended solids shall not exceed
one hundred(100)milligrams per liter when averaged over any three
consecutive samples.
d. To determine compliance with the standards contained in Section
30-6-10,samples shall be taken at least once per week, but no more
frequently than once per day.
D. Methods of Analysis - Sampling Points. All effluent samples shall be analyzed
according to the methods prescribed in the current edition of"Standard Methods for
the Examination of Water and Wastewater"(American Public Health Association).
Copies of the analytical methods allowed may be obtained, upon request,from the
I.S.D.S. Program Coordinator, Colorado Department of Public Health and
Environment. The point of sampling shall be a location that represents final
discharge from the system.
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Sec.30-6-20. Manufactured Units Utilizing Mechanical Apparatus for Treatment of Sewage.
A. Individual Sewage Disposal Systems utilizing mechanical apparatus and furnished
for installation in Colorado shall comply with the minimum requirements of criteria
and construction standards set forth in these regulations.
B. No such unit utilizing mechanical apparatus,which is designed for discharge,either
upon the ground or beneath the ground surface,or which may adversely affect state
waters, shall be permitted unless:
1. The system is installed within a geographic area in which a public,
quasi-public, or private entity, or political subdivision is continually
responsible for the efficient operation and maintenance of said unit,
2. Or, the operator of the system ensures an efficient operation of all
mechanical and electrical component parts provided prior to, and during,
continuing use.
Sec. 30-6-30. Approval of Systems Employing New Technology.
A. For purposes of this Section, a system employing new technology is a system
based on improvements and developments in technology of sewage disposal and
not otherwise provided for in the Individual Sewage Disposal Systems Act, Section
25-10-105 (1) (e)through (j), C.R.S., and possession and certification for systems
employing new technology from the Colorado Department of Public Health and
Environment as specified in Section XI of the Guidelines for Individual Sewage
Disposal Systems.The Board of Public Health shall not arbitrarily deny any person
the right to consideration of an application for such a system and shall apply
reasonable performance standards in determining whether to approve such an
application. (Section 25-10-107 (2), C.R.S.)
B. Systems awaiting a final decision by the Colorado Department of Public Health and
Environment on certification of an individual sewage disposal system employing new
technology, or systems for which a certification has been revoked, may be issued
a permit by the Weld County Board of Public Health for the system pursuant to
regulations adopted under Section 25-10-106(1)(g) of the Individual Sewage
Disposal Systems Act. Requirements for consideration of an experimental permit
shall include, but shall not be limited to:
1. The design specification, along with any previous laboratory or field test(s).
2. The necessary field tests shall be agreed upon by the manufacturer and the
Board of Public Health.
3. The installation shall be made as stipulated.
4. The field tests shall be made and the results of these tests shall be
submitted to the Division Representative. The manufacturer shall be
responsible for all test costs.
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5. The duration of the testing period shall be determined by the Board of Public
Health.
6. The manufacturer or designer shall warrant the design and installation, and
shall agree, in writing, to remove any unsatisfactory installation, as
determined by the Board of Public Health,within the time limit stipulated by
the Board. A backup system of an approved type shall be provided.
C. An unsatisfactory installation may be repaired or changed with the consent of and
observation by the Division Representative. However, the Board of Public Health
may limit the duration of the testing period, and may declare the design and
installation to be unsatisfactory. At that time,the Board of Public Health may require
the experimental system to be replaced by an acceptable installation or to be
removed from the designated lot. Failure to satisfactorily repair or remove an
unsatisfactory installation shall be deemed a violation of these regulations.
D. The application for an experimental system shall include provisions for the timely
installation of a backup system upon failure of the experimental system. The time
allowed for replacement and the design of the replacement system shall be
approved by the Division prior to installation of the experimental system.
Sec. 30-6-40. Effluent Discharged to State Waters.
A. Any system that will dispose of effluent by discharging into State waters shall be
designed by a Registered Professional Engineer, and the application shall be
submitted for preliminary approval to the Board of Public Health. Once approved,the
application shall be forwarded to the Colorado Department of Public Health and
Environment for issuance of a permit in compliance with all applicable regulations
of the Water Quality Control Commission. Compliance with such a permit shall be
deemed full compliance with all Individual Sewage Disposal System Regulations.
ARTICLE VII
Operation and Maintenance
Sec. 30-7-10. Responsibility.
The owner and the party in possession of real property upon which an individual sewage
disposal system is used, shall be jointly and severally responsible for operation and maintenance
of the system unless jurisdiction for responsibility has been transferred to a public,quasi-public,or
political subdivision. The person denying such responsibility shall bear the burden of proof for such
denial upon establishment of ownership or possessors'rights in the property served by the system.
Sec. 30-7-20. Service Label.
For treatment plants utilizing mechanical apparatus or under a service policy, a clearly
visible, permanently attached label or plate giving instructions for obtaining service shall be placed
at a conspicuous location.
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Sec. 30-7-30. Maintenance and Cleaning.
When directed by the Division, for the purpose of obtaining compliance with sections of
these regulations,the owner or user of a system shall provide for maintenance and cleaning of an
individual sewage disposal system. The owner or user shall notify the Division upon completion of
any maintenance work, and report to said Division with such evidence of compliance with any
maintenance and cleaning schedule in the form and as the Division requires.
A. To ensure that disposal systems continue in good working order the following
minimum schedule is recommended for all individual sewage disposal systems.
Table 30-8
Minimum Schedule
Type of Inspection/ Cleaned/ Routine Effluent
Treatment Maintenance Pumped Testing
Septic tank Every year Every 4 years Experimental
systems only
Vault, privies Every year As necessary None
Aeration plant Every 6 months Every 4 years Not more than 2
times /year
B. The owner of any septic system and vault shall maintain all pumping receipts for at
least five (5)years and shall make such receipts as are in the owner's possession
available to the Division for review upon written request of the Division.
C. The owner shall provide a pumping receipt from a locally licensed cleaner, for
inspection of existing systems for loan approval inspections and/or other inspections
deemed necessary by the Division, demonstrating that:
1. The tank has been inspected and pumped within the last two (2) years for
a new loan.
2. The tank has been inspected and pumped within the last four(4) years for
refinancing a loan.
Sec. 30-7-40. Monitoring and Sampling.
A. Reasonable periodic collection and testing by the Division of effluent samples from
individual sewage disposal systems for which monitoring of effluent is necessary to
ensure compliance with the provisions of rules and regulations, may be performed
not more than twice a year, unless required by the Division Representative in
conjunction with an enforcement action.
B. Any owner or occupant of property on which an individual sewage disposal system
is located may request the Division to collect and test an effluent sample from the
system. The Division may perform such collection and testing services. The
Division shall accept results conducted by the Colorado Department of Public Health
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and Environment and results conducted by a certified laboratory of the owner's
choice.
C. If the Division collects and tests effluent samples, a fee not to exceed that which is
allowed by Section 25-10-101 et. seq., C.R.S., may be charged for each sample
collected and tested. Payment of such charge may be stated in the permit as a
condition for its continued use.
Sec. 30-7-50. Disposal of Waste Materials.
Disposal of waste materials removed from a system in the process of maintenance or
cleaning shall be accomplished at a site approved by County officials in a manner which does not
create a hazard to the public health, a nuisance or an undue risk of pollution, and which complies
with state and local rules and regulations. (See Weld County Code Chapter23,Section 30-20-100
et seq., C.R.S., regulations promulgated thereunder, and Solid Waste Regulations.)
Sec. 30-7-60. Discharge Not Permitted.
No sewage or effluent shall be permitted to be discharged into or upon the surface of the
ground, or into state waters, unless the sewage system and effluent meets the minimum
requirements of applicable rules and regulations.
Sec. 30-7-70. Termination of Use of System.
The contents of a septic tank, vault, cesspool or seepage pit, the use of which has been
terminated,shall be properly disposed of whereon the emptied tank,vault, cesspool, or pit shall be
filled with soil or rock, or the Division Representative may require the tank or vault to be removed
and disposed of properly.
ARTICLE VIII
General Prohibitions and Penalties
Sec. 30-8-10. Adopt Individual Sewage Disposal Systems Act.
For purposes of administration and enforcement of the "Individual Sewage Disposal
Systems Act"(Article 10 of Title 25, C.R.S.),the following provisions of said Act specifying general
prohibitions and penalties, and are set forth for ease of reference.
A. (As a reference), Section 25-10-112, C.R.S.: General Prohibitions
1. No city, county, or city and county shall issue to any person a permit to
construct or remodel a building or structure which is not serviced by a
sewage treatment works, until a permit for an individual sewage disposal
system has been issued by the Division.
2. No city, county, or city and county occupancy permit shall be issued to any
person for the use of a building which is not serviced by a sewage treatment
works until a final inspection of the individual sewage disposal system has
been conducted and final permit issued by the local health department, as
provided for in Section 25-10-106(1)(h), C.R.S., and the installation has
received the approval of the Division.
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3. No individual sewage disposal system presently in use and that was installed
after October 1, 1975, which does not comply with the provisions of
Section 25-10-105(1)(e),C.R.S., regarding minimum separation between the
maximum seasonal level of the groundwater table and the bottom of an
absorption system shall be permitted to remain in use without compliance
with this Section and the rules and regulations adopted under this Section.
4. Construction of cesspools defined as covered underground receptacles
which receive untreated sewage from a building and permit the untreated
sewage to seep into surrounding soil are prohibited.
5. Not more than one (1) dwelling, commercial, business, institutional or
industrial unit shall be connected to the same individual sewage disposal
system unless such multiple connection was specified in the application
submitted and in the permit issued for the system.
6. No person shall construct or maintain any dwelling or other occupied
structure which is not equipped with adequate facilities for the sanitary
disposal of sewage without endangering the public health.
B. Section 25-10-113, C.R.S. Penalties
1. Any person who commits any of the following acts or violates any of the
provisions of this Section commits a Class 1 petty offense as defined in
Section 18-1-107, C.R.S.:
a. Constructs, alters, installs, or permits the use of any individual
sewage disposal system without first having applied for and received
a permit as provided for in Sections 25-10-105(1)(f) or 25-10-106,
C.R.S.;
b. Constructs, alters, or installs an individual sewage disposal system
in a manner which involves a knowing and material variation from the
terms or specifications contained in the application or permit;
c. Violates the terms of a cease and desist order which has become
final under the terms of Section 25-10-106(1)(k), C.R.S.;
d. Conducts a business as a systems contractor without having
obtained the license provided for in Section 25-10-108(1)C.R.S., in
areas which the Board of Public Health has adopted licensing
regulations pursuant to said section;
e. Conducts a business as a system cleaner without having obtained
the license provided for in Section 25-10-108(2), C.R.S., in areas
which the local Board of Public Health has adopted licensing
regulations pursuant to said section;
f. Willfully fails to submit proof of proper maintenance and cleaning of
a system as required by rules and regulations adopted pursuant to
Section 25-10-106, C.R.S.
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ARTICLE IX
Variance Procedure
Sec. 30-9-10. General.
The Division may set fees for processing an Individual Sewage Disposal System(I.S.D.S.)
permit with a variance in accordance with the provisions of Section 25-10-107 of the Individual
Sewage Disposal Systems Act. This permit fee may be the standard I.S.D.S. permit fee or may be
a separate fee based upon the cost of processing a permit with a variance.
Sec. 30-9-20. Requirements for Variance Consideration.
A. The Weld County Board of Public Health must hear variance cases and approval of
a variance requires a majority vote.
B. Prior to the rendering of a decision on a variance request,a Public Hearing must be
held. The hearing shall be the subject of a Public Notice or notice shall be sent via
certified mail, with a minimum twenty (20) day reply time from the date of mailing,
to all adjacent property owners. The applicant may submit a signed and dated
statement of acknowledgment of variance from all adjacent property owners in lieu
of posting or mailing.
C. Requests must be accompanied by:
1. Site specific request identifying the specific criteria from which a variance is
being requested.
2. Technical justification by a Colorado Registered Professional Engineer or
Professional Geologist,which indicates the specific conditions which exist
and/or the measures which will be taken to result in no greater risk than that
associated with compliance with the requirements of the regulation.
Examples of conditions which exist, or measures which might be taken,
include but are not limited to the following:evidence of a natural or physical
barrier to the movement of effluent to or towards the feature from which the
variance is requested; placement of a manmade physical barrier to the
movement of effluent to or toward the feature from which the variance is
requested; soil amendment or replacement to reduce the infiltration rate of
the effluent such that the travel time of the effluent from the absorption field
to the physical feature is no less than the travel time through the native soils
at the prescribed setback; and treatment equivalent to that required to meet
National Sanitation Foundation (NSF) Standard 40 be provided.
3. A discussion of alternatives considered in lieu of the requested variance;
4. Technical support for selected alternative, which may include a testing
program, which confirms that the variance does not increase the risk to
public health and to the environment; and
5. A statement of the hardship, which creates the necessity for the variance.
No variance will be allowed solely for economicgain.
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D. The applicant has the burden of proof that the variance is justified and will pose no
greater risk to public health and the environment than would a system meeting the
requirements of the regulation.
E. The Division has the ability to impose requirements and conditions on any variance
granted.
Sec. 30-9-30. Outcome of the Variance Proceeding.
The applicant shall be notified,in writing,of the decision regarding the request fora variance.
The notice of a denial of a variance shall include those reasons which form the basis for the denial.
The notice of an approval of a variance shall include any conditions of the approval. The variance,
and any conditions thereof shall be recorded on the deed to the property, and any expenses
associated with that recording shall be the responsibility of the party obtaining the variance.
Sec. 30-9-40. Right to Appeal.
Should the Board of Public Health deny an appeal under Article IX hereof,the applicant shall
have the right to appeal such decision to the Weld County Board of County Commissioners
pursuant to Section 3-8(4)(n) of the Weld County Home Rule Charter and the procedures
promulgated thereunder.
Sec. 30-9-50. Prohibitions on the Granting of Variance Requests.
A. No variance will be issued to mitigate an error in construction involving any element
of property improvements.
B. No variance will be issued where the property can accommodate a conforming
I.S.D.S.
C. No variance will be issued which will result in setbacks to an off-site physical feature
which do not conform to the minimum setbacks defined in Appendix 30-B.
D. No variance will be issued which reduces the four(4)foot separation to groundwater
or bedrock.
E. No variance from the horizontal setback from a well shall be given which does not
also meet the variance requirements of the Board of Examiners of Water Well
Construction and Pump Installation Contractors.
Sec. 30-9-60. Findings on Appeal.
A. Any applicant whose permit or variance application has been denied by the Division
may request review of the application by the Board of Public Health.
B. A request for review shall be made within sixty (60) days after denial.
C. The applicant shall bear the burden of supplying the Board of Public Health with
sufficient evidence to document that the denied system will be constructed and used
in such a manner as to comply with the declaration and intent of these guidelines
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and all applicable state and local rules and regulations and required terms and
conditions in any permit pursuant thereto.
D. Such review shall be conducted pursuant to the requirements of Section 24-4-105,
C.R.S.
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PAGE 51 ORD2005-5
APPENDIX 30-A
QUANTITIES AND BOD STRENGTH OF SEWAGE
FOR VARIOUS TYPES OF USES
GALLONS/PERSON/DAY LBS.
TYPE OF ESTABLISHMENT (AVERAGE) BOD5/PERSON/DAY
(UNLESS OTHERWISE (UNLESS OTHERWISE
STATED) STATED)
Residential
Single-family dwellings
(two people per bedroom) 75 .20
Separate Distribution of Flows -
Individual Residential use
Bath/Shower 14.7 .014
Dishwasher 1.8 .002
Kitchen sink 4.4 .045
Additional for garbage grinder 1.4 .052
Laundry washer 19.5 .037
Lavatory 8.4 .021
Water closet 24.8 .029
Hotels and Motels - per room
(without private baths) 50 .15
Hotels and Motels - per room
(with private baths) 75 .15
Multiple-family dwellings or apartments 75 .20
Boarding and Rooming houses 50 .15
Mobile Home Parks 75 .20
(per space) 300 .80
Commercial
Airports (per passenger) 5 .02
(per employee) 10 .06
Barber and Beauty Shops
(per chair) 100 .70*
Bowling Alleys
(per lane - toilet wastes only) 5 .03*
Bus Service Areas
(not including food) 5 .02
Country clubs
(per member) 30 .02
(per employee) 20 .06
Dentist offices
(per non-wet chair) 50 .14*
Doctors offices (per doctor) 250 .80*
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Fairgrounds
(per person attending) 5 .02
Factories and plants
(exclusive of industrial wastes)
(per employee per 8-hour shift-no
showers) 20 .05
(per employee per 8-hour shift-
showers provided) 35 .08
Food service establishments
I (per seat- including employees)
Restaurant (Open 1 or 2 meals) 50 .06/meal served
24-hour Restaurant 75 .07/meal served
Restaurant with paper service only 25 .01/meal served
Additional for bars and cocktail
lounges 30 .02
Drive-in Restaurant
(per car space) 50 .02
Kennels (per dog)
I boarding and grooming 30 .20
I sanitation only (greyhound, etc.) 10 .06*
Laundries, self-service
(per commercial washer) 400 .75
Office Buildings
(per employee per 8-hour shift) 15 .06
Stores and Shopping Centers
(per square foot of Retail space) .1 .01*
Service Stations
(per toilet fixture) 250 .50*
Stadiums, Race Tracks, Ball Parks
(per seat) 5 .02
Theaters (Movie, Indoor, or Auditorium) 5 .02
Work or construction camps
(semi-permanent-with flush toilets) 50 .17
Work or construction camps
(semi-permanent-without flush toilets) 35 .02
Institutional (does not include kitchen
wastewater flows)
Churches (not including food) 5 .01
Hospitals (per bed space) 250 .20
Nursing Homes (per bed space) 100 .17
Schools, Boarding 100 .17
Schools, Day
(without cafeteria, qym or showers) 15 .04
(with cafeterias, no gym or showers) 20 .08
(with cafeterias, gym and showers) 25 .10
(additional for school workers) 15 .06
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Recreational and Seasonal
Camps, day(no meal served) 15 .12
Luxury Resort 125 .17
Resort (night and day) 50 .12
Campground (seasonal occupancy-
per unit)** 50 .12
Public Park (during hours when park is open)
- Flush Toilet
(per fixture per hour) 36 .04 lbs./fixture
-Urinal
(per fixture per hour) 10 .01 lbs./fixture
-Shower
(per fixture per hour) 100 .10 lbs./fixture
-Faucet
(per fixture per hour) 15 .04 lbs./fixture
Swimming pools and bathhouses 10 .06
Travel trailer parks
(with individual water and sewage 50 .12
hookup - per unit) **
(without individual water and sewage
hookup - per unit) ** 50
.12
* = BOD Levels needing further verification
** = Laundry facilities are to be calculated on a per commercial washer basis in
accordance with other elements of this table. SECTION 7: MINIMUM
HORIZONTAL DISTANCES BETWEEN COMPONENTS OF A SYSTEM AND
PHYSICAL FEATURES
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PAGE 54
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PAGE 55
APPENDIX 30-C
ANNUAL FREE WATER SURFACE
EVAPORATION MAP OF WELD COUNTY
ADAPTED FROM NOAA TR NWS 33
UNITS: INCHES/YEAR
45
40
•
Vann
+ 3r ggsdale
W'. ndsor
. Greeley
1
J •
ohnstown
(=t Lupton (I
/9 _t ie
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PAGE 56 ORD2005-5
APPENDIX 30-D
SOIL CLASSIFICATION SYSTEM (SOIL-SEPARATE SIZE LIMITS)
SOURCE: EPA Design Manual for Onsite Wastewater Treatment and Disposal Systems
NAMES MID SIZE LIMITS OF PRACTICAL-SIZE
CI ASSES ACCORDING TO SIX SYSIEMS
SYSTEM
1. U S Ou.ca1.ol '_...T r S • IITq I ' l t 17T ii----1-1rri-rni rT 1-1-I19--- __—rr1 i Ti---r_
Retlamillors and 5111 and Clay
Colas ol Ea rneels Ill S idislinot,slmd on she Mell' Cu..;s Coal se
9 1 Fine sand I' ,y.avel Conies
Oeo of he Ara.yl basis al plasticity) sand sand to
2. Amm.can ASSouaoot' a— Clay—.r 1
al Siam II.jiiwjV I Slit Fine sand Coalsc sand I Inc°ravel Meib.nn Coale Ilminle.l
OIl.cals ' Colloids J.avel 1 ylay.a
___i____ —
1 Amolican Society lot a_ _CIaY--r
Icumy and Ma1c..als I Slli Fine sand Medium C,... i.r
"'el
- -
Colloids santl 5auJ
Vv.y
4 WenlwegIr Clay Sill Vli bneee fine M. II "aa15
...I 1 111 s Cobbles
. -- - sand sand S''.."
r I .:oas se lii.innies
Y11
-
5.US Oepagmenr of vmy
Vely
aviculture Clay SITE Fine Medium Ip COW se
line sand floc gravel Coal se gr avcl (wades
Sand sand sand Coal se
__ Sandi_
6.Imc.nallonal Socmly
of Sml Science Clay Su. Floe sand Cum sc sand G.and
. —.I___—1. 1.A_r Lilt__ _1__L1JiLL_ ._.I 1_I_LLII{ _L_I.1.1 IA it-_1__.._J
0 000 0002 0.02 0.2 20 20 200
Panicle diameies,Imo
* Preferred System
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APPENDIX 30-E
TEXTURAL TRIANGLE DEFINING TWELVE TEXTURAL CLASSES OF THE USDA
(ILLUSTRATED FOR A SAMPLE CONTAINING 37% SAND, 45% SILT, AND 18% CLAY)
SOURCE: EPA Design Mfor Onsite Wastewater Treatment and Disposal Systems
100
.
94 .
aa.•aas...a .
aal..anaa.
a.
80--eta'' '.
'.
i.
aYY.iiir..laaa"MW: ala/W.
..aGaay.Staeaw s..aa�.�sacrat,3
70 iMat- •4An __
a�.,,�aa., . clay "a a.�, :
.VJiYLW__' Wa.iI..A..
V Y .W.
e �W„ d W
_YW../ ♦aaV.1�W.YYY
I �50.4 '� v •" ,W 3
cf fir.: silty
: sand; clay . .
-— clay at'..•r..-.». .T.."'�.�. tS
.y.PyY�Y,� .. �� silty clay "'�
30 IQ C 'lib. - loam t s.
W \O
sandy cl.y I•am _+------- a.
20, ..+. e
T... l
as acnats.,.....YYa►fYV WL_awl.-..'- +..uv,r wyi-.-i-�_ -r i.
Fw • ,r" .... �::. ate...
10 til iM " s.„'yI, m»: ' r�_ ':-=',7- --."—
' t
i s �a -
,�sm1.��loamy :..� , �• A"'Yaxx .�'..� . .r.,.sta Lyra
.....
sand •VMti —cc VaaYYY VaYY�.LVY VYYYY.VY.YY�1
1Qj $ S O 3 `S 5 'S 'S ♦2'
percent sand
Chart showing the percentages of clay (below 0.002 mm.1 .
silt (0.002 to 0.05 mm.), and sand (0.05 to 2.0 mm.) in the basic soil
textural classes.
From: USDA Soil Survey Manual 5, L-13, 7u8
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