Guidelines for Small Flow Sewage Treatment …

1 362-0300-002 8/983620-BK-DEP1624 Rev. 8/98(Formerly 3640-BK-DER1624) Guidelines FOR DESIGNINSTALLATION & OPERATIONOFSMALL FLOW Sewage Treatment FACILITIESD epartment of environmental ProtectionBureau of Water quality ProtectionAn Equal Opportunity EmployerThis manual and related environmentalinformation are available electronically viainternet. For more information, visit us throughthe Pennsylvania homepage at visit DEP directly at (choose Subjects/Water Management/WaterQuality Protection/Wastewater Management).362-0300-002 / August 1998 / Table of Contents / Page iTABLE OF CONTENTS for Sewage Tank(s).. Treatment Sand and and Reporting Design Annual Report Report of DEP / August 1998 / / Page iiCommonwealth of PennsylvaniaDepartment of environmental ProtectionSMALL flows FACILITIES DESIGN MANUALThe attached Small flows Facilities Design Manual has been prepared as a guide for persons responsible forthe design, installation and operator of Small flows Sewage Treatment (<2000 gpd) of facilities.

2 The manual isalso available to download from the DEP web site at: manual may be revised from time to time as the need arises. If you have suggestions for improvement tothis manual or desire that future revisions be sent to you, please return this letter to us with the followingcompleted this request made: Name Street or Route City State Zip Code Telephone E-mail This manual could be improved by

3 Yes, send me future revisions to the manualYes, please notify me of any revisions for downloading from DEP web to:Chief, Permits SectionPennsylvania Department of environmental ProtectionBureau of Water quality ProtectionRCSOB 11th Box 8774 Harrisburg, PA 17105-8774362-0300-002 / August 1998 / Page1 DEPARTMENT OF environmental PROTECTIONBUREAU OF WATER quality PROTECTIOND ocument ID:362-0300-002 Title: Small Flow Sewage Treatment Facility ManualEffective Date:February 1, 1998 AuthorityAct 537 of 1966, the Pennsylvania Sewage Facilities Act (as amended), and the Clean Streams Law ( ) 25 PA Code Chapter :To improve and preserve the purity of the waters of the Commonwealth for the protection of public health,animal and aquatic life and for :To amend and clarify the existing 8/91 guidance regarding the design and construction of domesticwastewater Treatment :This policy provides minor amendments to the 1/1/92 guidance regarding the design and construction ofsmall flow Treatment .

4 The policies and procedures outlined in this guidance are intended to supplement existing in the policies or procedures shall affect regulatory policies and procedures herein are not an adjudication or a regulation. There is no intent on the partof DEP to give the rules in these policies that weight or deference. This document establishes theframework within which DEP will exercise its administrative discretion in the future. DEP reserves thediscretion to deviate from this policy statement if circumstances Length:37 PagesLocation:Vol. 33, Tab 24 Definitions:Sewerage System: A system of Sewage collection, conveyance, Treatment and disposal which willprevent the discharge of untreated or inadequately treated Sewage or other wastes into waters of theCommonwealth or otherwise provide for the safe and sanitary Treatment and disposal of Flow Treatment Facility: An individual or community sewerage system designed to adequatelytreat Sewage flows not greater than 2,000 / August 1998 / Page purpose of this Manual is to provide Guidelines for the design, installation and operation of Small Flow SewageTreatment Facilities (SFSTF).

5 These facilities are intended to serve single family residences, duplexes and smallcommercial establishments with domestic type Sewage (BOD consistent with Appendix A) not exceeding2000 gallons per day. For new building sites Small flow Sewage Treatment facilities are used to serve residentialdwellings only if on-lot systems cannot be used (See 25 Pa. Code, Chapter 71, Section ). For smallcommercial establishments with domestic type Sewage they may also be used only to repair or replacemalfunctioning systems. Small flow Treatment facilities must be capable of producing an effluent suitable fordischarge without violating NPDES permit limits or polluting groundwaters of the Commonwealth. They may not beused to discharge to any stream which is rated as Exceptional Value under Chapter 93 and may only discharge toHigh quality Streams when used to repair a malfunctioning treated Sewage from a Small flow Treatment facility may be discharged to a stream, dry stream, or applied toland by spray irrigation.

6 A number of Sewage disposal alternatives for Small flow situations exist and should beevaluated in the following order of to a public sewer disposal facility with spray facility with stream facility with dry stream flow Treatment facilities may only be used when on-lot disposal systems do not and cannot be expected tofunction satisfactorily because of soil, geologic and groundwater in the form of a permit (or permits where discharge to surface waters is involved) must be obtained fromthe Department prior to construction. Before any permits are issued Sewage planning approval is also manual will assist you in preparing the necessary information for your submission(s) to the Regional Office ofthe Department which serves the County in which the project is located. Department staff is available to assist youshould any questions YOU DECIDE TO PURSUE INSTALLATION OF A Small FLOW Sewage TREATMENTFACILITY, YOU SHOULD KNOW THAT THE APPROVAL PROCESS IS VERY TIMECONSUMING.

7 IT IS HIGHLY RECOMMENDED THAT YOU ALLOW AMPLE TIME FOR YOUTO SECURE NECESSARY / August 1998 / Page FOR APPROVALTHE DEPARTMENT MUST APPROVE THE SPECIFIC PROJECT AND ISSUE PLANNINGAPPROVALS AND THE APPROPRIATE PERMIT(S) BEFORE THE FACILITY IS CONSTRUCTEDAND first step in this process is the approval of the proposed method of Sewage disposal by the municipality as arevision to its Official Sewage Plan. The Department must review and approve this revision. If Departmentapproval has not already been obtained, the applicant may initiate the process by completing an Application ForSewage Facility Planning Module (Application) (see back page of this manual) and returning it to the local orRegional Office of the Department as instructed on the Application. The planning for a Small flow facility can takeas long as 180 days from the time the complete module is submitted to the municipality for the planning stage, the project sponsor must show the municipality and the Department the site meets theminimum suitability requirements and that adequate assurances that the system will be properly operated andmaintained are in place.

8 (See Chapter 71, Sections and ).Once conceptional planning is approved, permit(s) to construct and operate the system are required. A NationalPollutant Discharge Elimination System (NPDES) Permit for Discharge and a Water quality Management (WQM)Permit for design, construction and operation of the facility must be obtained from the Department. The WQMP ermit application must be prepared by a professional engineer registered in Pennsylvania. Permit applications maybe obtained by contacting the Regional Office of the Department. See the next page for a chart which more fullyexplains the approval / August 1998 / Page 4 Small FLOW Sewage Treatment FACILITYAPPROVAL PROCESSA pplication for on-lot Sewage system permit denied bythe Sewage Enforcement OfficerApplicant Submits Application for Sewage FacilitiesPlanning Module to the DepartmentAppropriate Planning Module Component Returned toApplicant with Appropriate Special Studies/Hydrogeologic Studies, Social & Economic JustificationEtc.

9 NotedApplicant Completes Planning Module and Submits toCounty and Local Planning Commission Submits Application for Sewage FacilitiesPlanning Module to the DepartmentDepartment Review and Approval (Approval letter,contains appropriate permit Application Part I, NPDES& Part II, CSL)Applicant Submits Completed Applications to theDepartment (w/proof of Act 14 compliance)Department Reviews Application, Submits Public NoticePackage (There is a 30 Day Mandatory CommentPeriod at This Point) & ApprovesMunicipality Processes and Forwards to DepartmentApplicant Builds System Contacts Department forInspectionAfter Department Approval Applicant Operates Systemand Reports YearlyApplicant Requests Department Site ScreeningAppropriate DEP Staff Review SitePERMITTINGPROCESSPLANNING362-0300-00 2 / August 1998 / Page 5362-0300-002 / August 1998 / Page Small flow Treatment facility must be capable of continuously producing a suitable effluent without causingwater pollution or public health nuisances.

10 Minimum (30 day average) Treatment requirements for anydischarge is 25 mg/l C-BOD5 and suspended solids of 30 mg/l with effective disinfection. Since this is aminimum, however, some streams, dry streams, or spray sites may have more stringent effluent limits. Theseare determined by the Department as part of the approval process. The technology utilized must be relativelyfail safe and simple to operate and maintain by an unskilled individual. (General Design details are found inAppendix B.) All SFSTF s must include, at minimum, an initial Treatment unit, (septic tanks system or aerobictreatment tank), a buried sand filter, disinfection unit (erosion chlorinator and contact tank), and a discharge unit(outfall sewer or spray field). design capacity for the Small flow Treatment facility shall be based on the single family residence shall be designed based on a minimum flow of 400 gpd and a minimum organicload of lbs.