OAC 252:656-3-4
Engineering report
Cite as Okla. Admin. Code § 252:656-3-4
(a) Applicants shall submit to DEQ two (2) copies of the engineering report for proposed
new construction or modifications to sewage collection systems, or treatment works at least
thirty (30) days prior to the submittal of plans and specifications. Applicants shall also
submit a letter in which the applicant endorses the contents of each engineering report
submitted to DEQ. For line extension and lift station construction, the submission of an
Engineering Report Form, developed by DEQ, signed and sealed by an engineer licensed
by the State of Oklahoma, may be submitted to meet the requirements of the necessary
engineering report, unless a full engineering report is required by DEQ. Engineering
reports shall include:
(1) Volume and strength of sewage flow. Establish the existing and anticipated design
average and design peak flows and waste load for the existing and ultimate conditions.
Include the basis for projecting initial current and/or future dry and wet weather flows
and waste load for the existing, or initial, service area, and the anticipated future service
area. For discharging facilities, the report must demonstrate that the proposed project
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complies with the design flow in the 208 Plan and other applicable OPDES permit limits.
(2) Existing system. Describe the existing system, including the need for the project
related to health and safety, system operations and maintenance, and population growth.
Issues that must be addressed include, but are not limited to, suitability of existing
facilities for continued use, adequacy of water supply, history of compliance with state
and federal requirements, and comparison of existing treatment units with state and
federal design requirements.
(3) Project description and alternatives. The report must contain a description of the
alternatives that were considered to meet the identified need. Provide a service area and
project site maps showing the existing and proposed systems. The information must
describe legal and natural boundaries, major obstacles, elevations, and any other
information necessary to properly evaluate the project. Describe the proposed project
and, where two or more solutions exist, discuss the alternatives including cost analysis
and discuss the reasons for selecting the one recommended. For each alternative
considered, the report must provide the following:
(A) Description. A description of the collection system, pumping systems,
treatment, and discharge facilities associated with each alternative as applicable.
(B) Design criteria. The design parameters used for evaluation purposes.
(C) Schematic. A schematic diagram(s) of all existing and proposed treatment
processes.
(D) Land requirements. The identification of sites and easements that will be
used and whether the sites:
(i) are currently owned or leased by the applicant, or
(ii) will be acquired or leased by the applicant.
(E) Construction problems. A discussion of concerns such as subsurface rock,
high water table, limited access, or other conditions that may affect the cost of
construction or the operation of the facility.
(F) Advantages and disadvantages. A description of the ability of each
alternative to meet the owner’s needs, address violations cited in any
enforcement orders, satisfy public and environmental concerns, and comply with
regulatory requirements. The report must demonstrate the compatibility of each
alternative with existing, comprehensive, and area-wide development plans.
Provide a short description of environmental impacts that may preclude any
alternatives.
(G) Selected alternative. A complete description of the proposed project based
on the general description presented in the evaluation of alternatives. The report
must show that the proposed project will comply with all the requirements of
this Chapter. At a minimum, the following information must be included:
(i) Treatment. A description of the processes, including biosolids
management, in detail and the identification of the location of the plant
and the site of any discharges; a status of compliance with the 208
Plan, and if applicable, include current revisions with copy of DEQ
approval letter, if approved in the current 208 Plan.
(ii) Pumping stations. The size, type, location and any special power
requirements, including provisions for emergency operations, of all
pumping stations.
(iii) Collection system layout. Identify general location of line
improvements, including: lengths, sizes and key components.
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(iv) Calculations. Provide supporting calculations in sufficient
detail to demonstrate compliance with DEQ design requirements to
assure adequate capacity for the collection and treatment system as a
whole to transport and treat the wastewater or reclaimed water. For
collection system projects, the submittal must include a map with a
list of manholes and pipes and the associated characteristics, such as
elevation of inverts, pipe diameter, pipe segment length, and other
information necessary to evaluate the project. The report must provide
assurance that the receiving collection and treatment systems have
adequate capacity.
(4) Construction sequence. A description of the sequence of construction and steps
needed to maintain compliance during construction. If the project is not to be completed
in one sequence, then provide details of the phases.
(5) Site. Describe the topography, soils, geologic conditions, depth to bedrock,
groundwater level, floodway or floodplain considerations, and other pertinent site
information. The project must be constructed on the site consistent with approved plans.
Include 6 months of data on the groundwater level. Provide soil boring information
pursuant to OAC 252:656-11-3 (a) for projects that include lagoons or other non-
industrial impoundments.
(6) Water supply. Identify surface water intakes within five (5) miles of the discharge
and known public and private water wells within three hundred feet (300').
(7) Receiving stream.
Identify the receiving stream and its wasteload
requirements according to the Water Quality sections of OAC 252:606 and
Oklahoma’s Water Quality Management Plan (208 Plan).
(8) Disposition of biosolids. Discuss the available alternatives for biosolids reuse
and/or disposal (OAC 252:606 and OAC 252:515). Submit a sludge management or
sludge disposition plan to DEQ for approval. All biosolids that will be land applied
and/or disposed in a landfill must comply, at a minimum, with the Class B pathogen
reduction requirements contained at 40 CFR, Part 503, adopted by reference at OAC
252:606.
(9) Industrial wastes. Discuss the characteristics and volume of anticipated
industrial wastes.
(10) Collection system. Describe the area to be served by existing and proposed
sewers. Sewer capacities must be designed for the estimated ultimate population that
will be served. Similarly, consideration must be given to the maximum anticipated
loadings from institutions, industrial parks and other similarly situated facilities.
(11) Financing. Provide itemized cost estimates to build, operate and maintain
the proposed project including, but not limited to:
(A) development, construction, land and rights-of-way, legal services,
engineering services, contingencies, refinancing, and any other factors
associated with the proposed project;
(B) discuss financing methods;
(C) provide information regarding rate structures, annual operating and
maintenance (O&M) cost, tabulation of users by monthly usage categories and
revenue received for the last three fiscal years; and
(D) give status of existing debts and required reserve accounts. Include a
schedule of short-lived assets and a recommended annual reserve deposit to fund
replacement of short-lived assets such as pumps, paint and small equipment.
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(12) Enforcement orders. Discuss all applicable enforcement orders, including
the violations cited in the orders and how the project will eliminate said violations.
(13) Conclusions and Recommendations. Provide any additional findings and
recommendations that must be considered in development of the project. This must
include:
(A) recommendations for a specific course of action to be undertaken;
(B) any special studies to be developed;
(C) highlight the need for special coordination, include a recommended plan of
action to expedite project development, etc.
(14) Project Schedule. The report must propose a schedule to:
(A) obtain funds to complete the proposed project;
(B) submit construction plans, specifications, and permit application(s);
(C) start construction;
(D) complete construction, and
(E) attain compliance with applicable OPDES discharge permits.
(b) Water reuse treatment and reclaimed water distribution systems. Applicants
shall submit to DEQ two (2) copies of the engineering report for proposed new
construction or modifications to water reuse treatment and reclaimed water distribution
systems. Engineering reports shall be submitted at least thirty (30) days prior to the
submission of plans and specifications and all engineering reports submitted to DEQ shall
be signed and sealed by an engineer licensed by the State of Oklahoma. Applicants shall
also submit a letter in which the applicant endorses the contents of each engineering report
submitted to DEQ. For line extension and lift station construction, the submission of an
Engineering Report Form, developed by DEQ, signed and sealed by an engineer licensed
by the State of Oklahoma, may be submitted to meet the requirements of the necessary
engineering report, unless a full engineering report is required by DEQ. Engineering
reports shall include the following, as applicable:
(1) Volume and quality of reclaimed water flow. Describe anticipated flow from
wastewater treatment works to the water reuse treatment facility. For discharging
facilities, the report must demonstrate how the proposed project impacts the design
flow in the 208 Plan and other applicable OPDES permit limits.
(2) Existing system. Describe existing wastewater treatment and water reuse systems.
Descriptions shall include: the suitability of existing facilities for continued use,
adequacy of water supply and the facility's history of compliance with state and federal
requirements.
(3) Project description. Provide service area and project site maps showing the
existing and proposed systems. The information shall describe legal and natural
boundaries, elevations, major obstacles and any other information necessary to properly
evaluate the project.
Project descriptions shall include the following:
(A) Description. A description of the wastewater treatment system preceding
the water reuse treatment facility.
(B) Design criteria. The design parameters used for evaluation purposes.
(C) Schematic. Schematic diagrams of all existing and proposed treatment
processes.
(D) Land requirements. Identification of the sites and easements that will be
used and whether the sites:
(i) are currently owned or leased by the applicant, or
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(ii) will be acquired or leased by the applicant.
(E) Treatment. A detailed description of the treatment processes, including
biosolids management, identification of the location of the plant and the site
of any discharges:
(i) Pumping stations. Identify the size, type, location, any special
power requirements and provisions for emergency operations of all
pumping stations.
(ii) Reclaimed water distribution system layout. Identify the
general locations of line improvements, including lengths, sizes and
key components.
(iii) Calculations. Provide supporting calculations in sufficient detail
to demonstrate compliance with DEQ design requirements.
(4) Construction sequence. A description of the sequence of construction and steps
needed to maintain compliance during construction. If the project is not to be completed
in one sequence, then provide details of the phases.
(5) Site. Describe the topography, soils, geologic conditions, depth to bedrock,
groundwater level, floodway or floodplain considerations, and other pertinent site
information. The project must be constructed on the site consistent with approved plans.
Include 6 months of data on the groundwater level. Provide soil boring information
pursuant to OAC 252:656-11-3 (a) for projects that include lagoons or other non-
industrial impoundments.
(6) Biosolids handling. If the proposed project will increase the production of
biosolids and/or residuals, provide a description of any modifications necessary to
properly treat and dispose of biosolids. All biosolids that will be land applied and/or
disposed in a landfill must comply, at a minimum, with the Class B pathogen reduction
requirements contained at 40 CFR, Part 503, adopted by reference at OAC 252:606.
Submit a sludge management or sludge disposition plan as appropriate to the DEQ for
approval.
(7) Reclaimed water distribution system. A description of the following:
(A) The location, size, and direction of flow of all existing and proposed
reclaimed water distribution lines from the point of connection with the
existing or proposed treatment works or storage locations to the end user.
(B) A summary of quantities that includes, at a minimum, pipe size, materials
and linear feet of piping, types of testing and number and size of pumps.
(C) The disinfection system design based on one of the following criteria:
(i) maintaining a chlorine residual to end-of-pipe pursuant to
Appendix A of OAC 252:627; or
(ii) a DEQ approved calibrated model of chlorine decay rate in the
distribution system to demonstrate that adequate chlorine residual will
be maintained to prevent slime growth and regrowth of pathogens to
end-of-pipe.
(8) Financing. Itemized cost estimates to build, operate and maintain the proposed
project including, but not limited to:
(A) development, construction, land and rights-of-way, legal services,
engineering services, contingencies, refinancing, and any other factors
associated with the proposed project;
(B) financing methods;
(C) information regarding rate structures, annual operating and maintenance
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(O&M) cost, tabulation of users by monthly usage categories and revenue
received for the last three fiscal years; and
(D) the status of existing debts and required reserve accounts. Include a
schedule of short-lived assets and a recommended annual reserve deposit to
fund replacement of short-lived assets such as pumps, paint and small
equipment.
(9) Enforcement orders. A discussion of all enforcement orders, identifying the
violations cited in orders and explaining how the project will eliminate those violations.
(10) Conclusions and Recommendations. All engineering reports shall include a
recommendation for a specific course of action to be undertaken. The conclusions and
recommendations shall also include any additional findings, identify any special studies
to be developed, and any other recommendations that must be considered in
development of the project.
(11) Project Schedule. A proposed schedule to obtain funds to:
(A) complete the proposed project;
(B) submit construction plans, specifications, and permit application(s);
(C) start construction;
(D) complete construction; and
(E) attain compliance with applicable OPDES discharge permits.
(c) Authorized design-build projects may use the flexible permitting process as approved in
the engineering report, including:
(1) Label cover documents prominently as “Design-build;”
(2) Provide completed attestation form from applicant certifying that project is design-build;
(3) Description of design packages, including the number (maximum of six), scope of each
package, expected schedule of each package, and expected schedule of completion for major
construction items;
(4) The engineering report will address the entire scope of the project at 100% completion.