Attach-1-SOW.pdf

Little River National Wildlife Refuge Statement of Work

Installation of Aerobic Septic System

General: The Little River NWR has two park model mobile homes (12’ x 34’) located at 5357 South Park Drive in Broken Bow, Oklahoma that require the installation of one aerobic septic system to support the two mobile homes.

Scope of Work: The contractor shall provide all labor, equipment, materials, and submit an “Authorization to Construct an On-site Sewage Treatment System” to install an aerobic septic system in accordance with on-site wastewater systems described in Title 252. Oklahoma Department of Environmental Quality (DEQ) Chapter 641, Individual and small public on-site sewage treatment systems. The aerobic septic system will support the two park model mobile homes, each which are approximately 408 square foot of livings space, with two bedrooms, kitchen, full bathroom, and washer/dryer.

Specific requirements for the aerobic septic system can be found in SUBCHAPTER 10. AEROBIC TREATMENT SYSTEMS of Title 252. Oklahoma Department of Environmental Quality Chapter 641, Individual and small public on-site sewage treatment systems (attached document):

Specific requirements for authorization, permitting, and installation of aerobic septic systems can be found in SUBCHAPTER 10. AEROBIC TREATMENT SYSTEMS.

The following DEQ requirements outlined in Title 252: Chapter 641shall be met in the installation of the aerobic septic system:

252:641-1-2.1. Authorizations and permits for on-site sewage treatment systems

(a) Requirement for authorizations and permits. Before installing a new or modifying an existing on-site sewage treatment system, the installer shall first obtain either:

(1) DEQ authorization to construct an on-site sewage treatment system under the general permit, the terms of which are the rules of this Chapter; or

(2) an individual permit to construct an alternative on-site sewage treatment system.

(b) Applying for authorizations; necessity for permit.

(1) An installer seeking an authorization to construct a new or modify an existing on-site sewage treatment system shall submit a completed and signed:

(A) DEQ Form 641-575, "Request for Authorization/Permit to Construct an On-Site Sewage

Treatment System" along with the appropriate fee(s) [see 252:641-23 (relating to fees)] to DEQ's Oklahoma City office;

(B) DEQ Form 641-581P or 641-581SP "Report for On-Site Sewage" to the local DEQ office.

The detail needed varies with each system design; guidance will be provided by the local DEQ office; and

(C) DEQ Form 641-581Cert "Certification Documentation Form" to the local DEQ office.

(2) Any construction or modification design that deviates from the rules in this Chapter will require the installer to apply for an individual permit to construct a new or modify an existing alternative system.

(c) Applying for permits for alternative systems. Installers seeking an individual permit to construct a new or modify an existing alternative on-site sewage treatment system shall submit a completed and signed:

(1) DEQ Form 641-575, "Request for Authorization/Permit to Construct an On-Site Sewage

Treatment System" along with the appropriate fee(s) [see 252:641-23 (relating to fees)] to DEQ;

(2) DEQ Form 641-581P or 641-581SP "Report for On-Site Sewage" to the local DEQ office;

(3) DEQ Form 641-581Sup., "Supplemental Application for an Alternative On-Site Sewage

Treatment System" to the local DEQ office for DEQ's review and approval; and

(4) DEQ Form 641-581Cert "Certification Documentation Form" to the local DEQ office.

SUBCHAPTER 10. AEROBIC TREATMENT SYSTEMS

Section 252:641-10-1. Residential sewage treatment only 252:641-10-2. Design and installation 252:641-10-3. Responsibility for maintenance

252:641-10-1. Residential sewage treatment only Aerobic treatment systems shall only be used for treatment of sewage from residential units and cannot be used when the average daily flow is less than one hundred (100) gallons per day or greater than one thousand five hundred (1,500) gallons per day.

252:641-10-2. Design and installation

(a) Fluctuating flows. If the daily flow fluctuates so that the flow on any given day during the week exceeds the aerobic treatment unit's daily capacity, then an aerobic treatment system may not be used unless a flow equalization tank, which meets the requirements of 252:641-9, is installed between the trash tank and the aerobic treatment unit.

(b) Components of aerobic treatment systems. Aerobic treatment systems shall be comprised of the following components:

(1) Trash tank. There shall be a trash tank that meets the requirements of ANSI/NSF Standard 40 or 252:641-7-2. The trash tank shall:

(A) be constructed to prevent sewage from leaking out of the tank and to prevent the infiltration of water into the tank;

(B) have a minimum liquid capacity of three hundred (300) gallons or the average daily flow, whichever is greater, except that the minimum liquid capacity shall not be less than what was used in the ANSI/NSF certification process;

(C) have a removable lid or a manhole opening of sufficient size to allow for maintenance. The lid or manhole shall be sealed to prevent leakage and extend a minimum of two inches (2") above ground elevation. The cover for the opening shall have a lock, locking bolt or some type of fastener, or require a tool for removal; and

(D) have baffles installed at its inlet and the outlet. The baffles shall extend to within two inches (2") of the top of the trash tank.

(i) Inlet. Inlet baffles shall extend at least six inches (6") below the liquid depth of the trash tank.

(ii) Outlet. Outlet baffles shall extend below the liquid level by twenty percent (20%) to forty percent (40%) of the liquid depth.

(2) Aerobic treatment unit. There shall be a aerobic treatment unit that:

(A) has been tested and certified by an ANSI accredited third party certifier as meeting the most current ANSI/NSF Standard 40 and when required by waterbody restrictions ANSI/NSF Standard 245;

(B) is constructed to prevent sewage from leaking out of the tank and to prevent the infiltration of water into the tank

(C) is rated at or above the design daily flow;

(D) produces effluent clear enough that the bottom of the pump tank is visible when it is full;

and

(E) has an opening of sufficient size to allow for maintenance that extends a minimum of two inches (2") above ground elevation. The cover for the opening shall have a lock, locking bolt or some type of fastener, or require a tool for removal.

(3) Method of disinfection. If spray irrigation is used as the type of dispersal, then there shall be a method to disinfect the effluent that has been tested and certified by an ANSI accredited third party certifier as meeting the most current ANSI/NSF Standard 46, between the aerobic treatment unit and the pump tank (or in the pump tank). If chlorination is used as the disinfection method, a free chlorine residual of two tenths of a milligram per liter (0.2 mg/l) must be maintained in the pump tank. All other methods of disinfection shall effectively reduce the fecal coliform count to less than two hundred colonies per one hundred milliliters (200/100 ml).

(4) Pump tank. There shall be a pump tank, which shall:

(A) meet the requirements of ANSI/NSF Standard 40 or 252:641-7-2;

(B) have a minimum liquid capacity of seven hundred (700) gallons or, for systems with an average flow over three hundred fifty (350) gallons per day, have a liquid capacity of at least twice the average daily flow;

(C) have a sampling port in the pump tank at the discharge outlet or in the treated effluent line following the pump tank;

(D) have a float in the pump tank set so that the pump tank is never more than one-half (1/2) full;

(E) have a high-water alarm set to activate and alert the owner/operator if the pump tank becomes more than one-half (1/2) full; and

(F) have an opening of sufficient size to allow for maintenance that extends a minimum of two inches (2") above ground elevation. The cover for the opening shall have a lock, locking bolt or some type of fastener, or require a tool for removal.

(c) Dispersal field. Effluent treated by an aerobic treatment unit shall be dispersed as described in Subchapter 12 of this Chapter Level. Once installed, the top of each tank (i.e., trash tank, aerobic treatment unit and pump tank) shall have no more than one inch (1") variation in elevation from side to side and end to end.

(d) Depth of aerobic treatment system components. The top of all components of the aerobic treatment system, excluding the trash tank and dispersal field, shall be covered with no more than twenty-four inches (24") of soil.

(e) Solid pipe. The solid pipe used to connect the components of an aerobic treatment system must meet the minimum specifications listed in Appendix C.

(f) Fall. Unless a lift pump is utilized, there shall be fall between:

(1) the trash tank and the aerobic treatment unit; and

(2) the aerobic treatment unit and the pump tank.

(g) Manufacture's specification. All aerobic treatment systems shall be installed in accordance with the manufacturer’s specifications.

252:641-10-3. Responsibility for maintenance

(a) Mandatory two year maintenance period. The installer of any aerobic treatment system including those providing nitrogen reduction shall maintain the aerobic treatment system for a period of two years following the date the system was installed at no additional cost to the owner. During the two-year mandatory maintenance period, the installer shall be responsible for the following:

(1) repairing, adjusting or replacing any broken or malfunctioning parts;

(2) when spray dispersal is used, testing and recording the free chlorine residual of the effluent in the pump tank at least once every six (6) months;

(3) measuring and recording the depth of the sludge in the trash tank at least once every six (6) months;

(4) measuring and recording the volume of the sludge in forced-air aerobic treatment units at least once every six (6) months;

(5) when pump tanks are used, conducting a clarity test and recording the results as passing or failing once every six (6) months. A passing clarity test is one where an eight-inch disk with alternating black and white quadrants is visible when placed on the bottom of the pump tank when the tank is at least one-third (1/3) full;

(6) notifying the owner of the system in writing of:

(A) the type and date of any repairs, adjustments or replacements performed on the system;

(B) the results of the free chlorine residual test if required and, when applicable, the need to add chlorine and how to do it;

(C) the depth of the accumulation of sludge in the trash tank and the need to have it pumped so that the depth of the sludge is never more than forty percent (40%) of the overall depth;

(D) the volume of the sludge in the aerobic treatment unit and the need to have it pumped so that the volume of the sludge in the aerobic treatment unit is never more than forty percent (40%); and

(E) the results of the clarity test and, if it fails the test, what the installer did or the homeowner has to do to correct it; and

(7) documenting all maintenance and testing performed on the system and maintaining those records at his/her business for a period of three (3) years following the date of service.

(b) Exclusions from maintenance. The installer shall not be responsible for repairing aerobic treatment systems when the owner/operator is the sole cause of the damage to the system or the system's malfunction (e.g., sprinkler heads that properly retract into the ground but are nevertheless damaged by careless actions of the homeowner, excessive water usage, introduction of harmful items into septic system, etc.).

(c) Owner responsible after two year period ends. After the expiration of the two-year mandatory maintenance period, the owner of the aerobic treatment system shall be solely responsible for maintaining or hiring someone to maintain the system so that it operates as designed.

252:641-7-2. Types of tanks

(a) Concrete tanks. Concrete tanks shall be reinforced with rebar or fiber, and constructed of a mixwhich demonstrates a twenty-eight-day compressive strength of four (4) thousand pounds per square inch (4,000 psi). They may be poured in place or precast, but, in either case, shall be monolithically poured and mechanically vibrated.

(b) Fiberglass and plastic tanks. Fiberglass and plastic tanks shall meet either IAPMO or CSA standards for septic tanks and shall be installed according to the manufacturer's recommendations. If the tank does not bear the IAPMO or CSA mark, then DEQ will require the installer to submit documentation from IAPMO or CSA stating the tank meets the above standards.

APPENDIX C. PIPE SPECIFICATIONS FOR ON-SITE SEWAGE TREATMENT

SYSTEMS

USE PIPE SIZE ACCEPTABLE MATERIALS

Building sewer and other solid pipe when used for single family residences only

Minimum 3" diameter Acrylonitrile Butadiene Styrene (ABS):

ASTM D2661

ASTM D2751

ASTM F628

Building sewer and other solid pipe when the average flow is 2,000 gpd or less

Minimum 4" diameter Polyvinyl Chloride (PVC):

ASTM D2665

ASTM D2949

ASTM 3033

ASTM 3034

ASTM F789

Building sewer and other solid pipe when the average flow is greater than 2,000 gpd

Minimum 6" diameter

Discharge line from lift stations Polyvinyl Chloride (PVC):

or other pressurized effluent Minimum 1" diameter ASTM D2846 waste water lines† ASTM F441

ASTM F442

Schedule 40 Low pressure dosing manifold pipe 3" diameter

Low pressure dosing perforated 1 ½" diameter pipe

Perforated pipe when used in a conventional subsurface absorption field or an ET/A field

Minimum 3" diameter Polyethylene (PE):

ASTM F405

ASTM F810

ASTM D3350

Polyvinyl Chloride (PVC):

ASTM D2729

ASTM D3034

ASTM D3350

†All reclaimed, pressurized water piping shall be colored purple (Pantone 522) by the manufacturer.

The contractor is responsible for conducting business during the hours of 7:30 am to 4:00 pm, Mondays through Fridays except Federal holidays or when the Federal facility is closed due to local or national emergencies, administrative closings, or similar Government directed facility closings.

POC for Site Visit and SOW questions contact David Weaver, Refuge Manager at (580) 306-7277 email david_weaver@fws.gov

End

252:641-7-2. Types of tanks