Rules Establishing Minimum Standards Relating to Location, Design, Construction and Maintenance of Onsite Wastewater Treatment Systems


250-RICR-150-10-6 INACTIVE RULE

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6.1Purpose

6.2Authority

6.3Liberal Application

6.4Severability

6.5Applicability

6.6Administrative Findings

6.7Incorporated Materials

6.8Definitions

6.9Prohibitions

6.10Class I, II, III, and IV Licenses

6.11Obtaining a Class I, II, III or IV License

6.12Expiration and Renewal of a Class I, II, III or IV License

6.13Disciplinary Action for Class I, II, III and IV Licensees

6.14Installer's License

6.15Onsite Wastewater Treatment Systems – General

6.16Soil Evaluation

6.17Additional Site Testing

6.18OWTS Applications

6.19Required Content of OWTS Submissions

6.20Applications Involving the DEM Freshwater Wetlands Program and the Coastal Resources Management Council

6.21Subdivisions

6.22Wastewater Flow

6.23Minimum Setback Distances

6.24Subsurface Drains

6.25Building Sewers

6.26Grease Tanks

6.27Septic Tanks

6.28Septic Tank Effluent Pipe

6.29Holding Tanks

6.30Pump Tanks

6.31Pumps

6.32Distribution Boxes

6.33Leachfields

6.34Dispersal Trenches

6.35Concrete Chambers

6.36Pressurized Drainfields

6.37Advanced Pressure Drainfields (APDs)

6.38Low Pressure Pipe (LPP)

6.39Large OWTS Requirements

6.40Alternative Toilets

6.41Alternative or Experimental Technology Approval

6.42Critical Resource Areas – General

6.43Requirements in the Salt Pond and Narrow River Critical Resource Areas

6.44Requirements in Drinking Water Supply Watershed Critical Resource Areas

6.45Nitrogen Loading in Areas of Onsite Drinking Water Wells

6.46Permit Expiration

6.47OWTS Installation

6.48Certificate of Construction

6.49Certificate of Conformance

6.50Permit Suspensions and Revocations

6.51Variance Requests

6.52Variance Review Process

6.53Appeals

6.54Fees

6.55Operation and Maintenance

6.56Removal and Abandonment

6.57Cesspool Phase Out

6.58Guidance Documents


#x200e6.59Figure 1: Leachfield Over Restrictive Layer or Bedrock

6.60Figure 2: Minimum Setback Distances in Drinking Water Supply Watershed Critical Resource Areas

6.61Figure 3: Minimum Setback Distances in the Salt Pond and Narrow River Critical Resource Areas

6.62Figure 4: Grease Tanks

6.63Figure 5: Septic Tanks

6.64Figure 6: Septic Tank Riser Detail

6.65Figure 7: Leachfield Construction, Invert of Distribution Lines Below Original Grade

6.66Figure 8: Leachfield Construction, Invert of Distribution Lines Above Original Grade

6.67Figure 9: Leachfield Construction on Sloping Sites

6.68Figure 10: Shallow Concrete Chambers

6.69Figure 11: Category 1 Technology and Pressurized Drainfield Schematic

6.70Figure 12: Category 2 Technology and Pressurized Drainfield Schematic

6.71Figure 13: Demand Dosing Tank with Centrifugal Pump

6.72Figure 14: Demand Dosing Tank with Multi-stage Centrifugal Pump

6.73Figure 15: Timed-dosing Tank with Centrifugal Pump and In-line Screen

6.74Figure 16: Timed-dosing Tank with Centrifugal Pump and Basket Screen

6.75Figure 17: Timed-dosing Tank with Screened Vault and Multi-stage Centrifugal Pump

6.76Figure 18: Above-ground Bottomless Sand Filter (Side View)

6.77Figure 19: In-ground Bottomless Sand Filter (Side View)

6.78Figure 20: Typical Bottomless Sand Filter (Top View)

6.79Figure 21: Side View Detail – Typical Bottomless Sand Filter

6.80Figure 22: Orifice Shield Detail: Note: Shields Shall Be Able to Drain. Details Vary from Manufacturer.

6.81Figure 23: BSF Flushing Valve Choice Detail

6.82Figure 24: PSND Cross Section Details

6.83Figure 25: PSND Cross Section Detail (Long Side)

6.84Figure 26: LPP Details for Regular Trenches (Top and Isometric Views)

6.85Figure 27: LPP Details for Shallow Concrete Chambers (Top and Isometric Views)


6.86Figure 28: South Shore Salt Ponds Critical Resource Area


#x200e6.87Figure 29: Narrow River Critical Resource Area

6.88Figure 30: Providence Water Supply Board Drinking Water Supply Watershed

6.89Figure 31: Cumberland, Pawtucket Water Supply Board and Woonsocket Drinking Water Supply Watersheds

6.90Figure 32: Newport, New Shoreham and Stone Bridge Fire District Drinking Water Supply Watersheds

6.91Figure 33: Eleanor Slater/Zambarano Unit, Bristol County Water Authority, Yawgoog Scout Reservation, and Jamestown Drinking Water Supply Watersheds

Title 250 Department of Environmental Management
Chapter 150 Water Resources
Subchapter 10 Wastewater & Storm Water
Part 6 Rules Establishing Minimum Standards Relating to Location, Design, Construction and Maintenance of Onsite Wastewater Treatment Systems
Type of Filing Amendment
Regulation Status Inactive
Effective 12/28/2021 to 01/04/2022

Regulation Authority:

R.I. Gen. Laws Chapter 42-17.1 Environmental Management; Chapter 5-56 Installers of Individual Sewage Disposal Systems; Chapter 5-56.1 Designers of Individual Sewage Disposal Systems; Chapter 23-19.5 Percolation Tests and Water Table Elevations; Chapter 23-24.3 Substances or Compounds Used as Sewerage System Cleaners; Chapter 46-13.2 Drilling of Drinking Water Wells, and Chapter 23-19.15 Rhode Island Cesspool Act of 2007

Purpose and Reason:

The purpose of these amendments is to incorporate revisions made to R.I. Gen. Laws § 5-56.1-4 (Designers of Individual Sewage Disposal Systems- Conditions for obtaining a designer’s license) by the R.I. General Assembly in the 2019 session. The change in statute states that professional engineers, registered and authorized to practice engineering in Rhode Island, meet the minimum qualifications, experience, and education requirements for an OWTS designer’s license. This has the effect of exempting professional engineers from the testing and continuing education requirements to obtain and maintain a Class III Designer’s License.

Section 6.8- Definitions:

-Add definition of “Professional engineer.”

Section 6.11- Obtaining a Class I, II, III or IV License

-Section reorganized to place Class III license information into separate subsection. Subsection (A) includes existing requirements for Class I, II, and IV (Soil Evaluator) licenses. Language pertaining to Class III minimum qualifications and exam descriptions have been deleted from Subsection (A). Also, references to Professional Engineer credential as a minimum qualification for Class I and II licenses has been deleted. Subsection (B) includes requirements for obtaining a Class III license consistent with revisions made to R.I. Gen. Laws § 5-56.1-4 (Designers of Individual Sewage Disposal Systems- Conditions for obtaining a designer’s license).

-Existing requirement that licenses be issued only to natural persons moved to Subsection (C) to make clear that these requirements apply to all license classes.

Sections 6.12 (Expiration and Renewal of a Class I, II, or IV License):

- Section 6.12(B)(3) edited to incorporate revisions made to R.I. Gen. Laws § 5-56.1-4 (Designers of Individual Sewage Disposal Systems- Conditions for obtaining a designer’s license) stating Professional Engineers are exempt from continuing education requirements for license renewal.