AGENDA ITEM SUMMARY. AGENDA ITEM TITLE: Discussion on Onsite Wastewater Treatment System (OWTS) Regulation Options

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1 AGENDA ITEM SUMMARY WORK SESSION DATE: April 15, 2014 AGENDA ITEM TITLE: Discussion on Onsite Wastewater System (OWTS) Regulation Options STAFF RESPONSIBLE: Kurt Dahl, Environmental Health and Natural Resources ISSUE STATEMENT: Staff needs direction on optional amendments in the Onsite Wastewater System (OWTS) Regulation revision prior to sending these optional and required amendments to the Colorado Department of Public Health and Environment (CDPHE) for review. BACKGROUND: Staff is finishing the required changes to the Pitkin County OWTS Regulations. The required changes are due to CDPHE amending their OWTS Regulation #43 and Pitkin County s Regulations must meet the minimum requirements described in CDPHE Regulation #43. The formal adoption process is as follows: 1. Draft Regulations to CDPHE for initial compliance review 2. The Board of County Commissioners (BOCC), sitting as the Board of Health, approving the draft regulations with first and second readings 3. A 45-day grace period before the approved regulations take effect for additional CDPHE review. There are few sections of CDPHE Regulation #43 that are optional for each county. If a county chooses to include any or all option(s) then Regulation #43 outlines minimum requirements for each option. The options were created as a way to alleviate any political or staffing concerns associated with each option and still create minimum standards for those jurisdictions that choose to enforce/adopt them. LINK TO STRATEGIC PLAN: Flourishing Natural and Build Environment KEY DISCUSSION ITEMS: Prior to submitting the draft of our required and proposed amendments to CDPHE for review, staff would like to ensure the BOCC agrees with our recommendations about the options below. 1. The first option is whether to allow a reduction in the size of an OWTS soil treatment area (absorption field) and/or a reduction in some physical setbacks (i.e. wells, streams, dry gulches, etc.) to the OWTS with the installation of an advanced treatment unit. An advanced treatment unit has some additional processing of sewage that greater reduces nutrients and relies less on the soil for treatment. If the OWTS is relying less on the soil for treatment then it makes sense to allow the soil treatment area to be reduced in size or allow the OWTS to be closer than a conventional OWTS to some physical setbacks since the threat for contamination is lower. However, advanced treatment units require periodic maintenance and if a local jurisdiction

2 chooses this option then CDPHE also requires that jurisdiction to have a more robust and active management program to ensure these units are being maintained. An advanced treatment unit that is not maintained and not working properly will only perform as well as a conventional OWTS and in some cases it may perform worse. If we are going to allow for a reduction in sizing or a reduction in a setback, then we must make sure the OWTS is performing to manufacturer specifications. Our current OWTS Regulations allow for the installation of advanced treatment systems and it has operation and maintenance requirements. The biggest change for staff would be that we would be more active in ensuring advanced treatment systems are being maintained and this will require additional work. Staff recommends we adopt this option along with the use of renewable permits (option discussed below). Attached are two tables indicating the reductions that would be allowed in the new regulations. Table b shows the setback reductions to wells, lakes/streams, dry gulches, and ground water. To be more consistent with our Land Use Regulations, which require all new development to be 100 to any lake/stream, staff is recommending different setbacks than CDPHE with regards to lakes/streams as indicated in the following table. Minimum Setback requirements from lakes/streams to OWTS soil treatment area Levels 1 and 2 Level 2N Level 3 Level 3N Existing Pitkin County Regulations Proposed Pitkin County Regulations CDPHE Regulation # * level standards are defined by CDPHE. level 1 is a conventional OWTS system with increasing treatment as you move from level 2 to level 3N. The N indicates additional removal of nitrogen. Pressure dosing is required in addition to the required treatment level. Staff is proposing to not deviate from the CDPHE setback requirements for wells, dry gulches, and ground water. Table contains a lot of information and is quite busy but the pieces to pay attention to are the LTAR values in the advanced treatment columns 2, 2N, 3, and 3N. When compared to the treatment level 1 column, the values are larger and the intended effect is that the required soil treatment area size (absorption field) will be smaller. 2. A second option is the allowance to use/create a renewable permit. A renewable permit is issued like construction permits are now issued but the renewable permit is not finalized/closed and is renewed periodically to follow up on the use of the OWTS or other items that may need to be reviewed over time. This type of permit makes sense for systems that require maintenance, like advanced treatment units, and makes for a great way to track these types of systems. Staff recommends we adopt renewable permits, with a 2-year effective period, into our regulations with an effective date 1 year after the adoption of the regulations to allow for time to set up the program. Attached are the proposed renewable permit sections of the draft regulation

3 3. The other two options that staff recommends codifying are the prohibition of pit privies and slit trenches. These two options have been policy for several years and should be codified so our requirements are clear. BUDGETARY IMPACT: Low impact to the budget since the proposed renewable permit would have a minimal fee and the potential number of permits is estimated to be 100 annually. RECOMMENDED BOCC ACTION: Receive direction from the BOH on the proposed options and proceed with the OWTS Regulation adoption process showing the sizing and setbacks if reductions are allowed. ATTACHMENTS: 1. Tables b and from the proposed Pitkin County OWTS Regulations showing what the reductions in sizing and setbacks would be if we allow reductions. 2. Proposed renewable permit regulation

4 Table b On-site Wastewater System Design Consideration and Requirements Separation Distances from Soil Area PRESSURE DOSING REQUIRED ITEM OWTS DESIGN CONSIDERATION Levels 1 and 2 Level 2N Level 3 Level 3N Horizontal Separation Distances 1 Distance from soil treatment area to on-site well or equal to 100 or equal to 100 or equal to 100 or equal to Distance from soil treatment area to pond, creek, lake, or other surface water feature or equal to 100 or equal to 50 or equal to 50 or equal to 50 3 Distance from soil treatment area to dry gulch or cut bank or equal to 25 or equal to 10 or equal to 10 or equal to 10 Vertical Separation Distances 4 Depth in from soil treatment area infiltrative surface to restrictive layer or ground water 4 (3 with pressure dosing) or equal to 2 or equal to 2 or equal to 2 NOTE: levels are defined in Table 6-2b. Reductions in separation distances with higher level treatment may be granted only if the local public health agency regulations have included provisions for operation and maintenance. 1 Prior to approval, all setback distance reductions to the 100 foot requirement for wells and soil treatment areas must be in full compliance with the minimum standards and variance requirements of the State of Colorado Division of Water Resources: Rules and Regulations for Water Well Construction, Pump Installation, Cistern Installation, and Monitoring and Observation Hole/Well Construction.

5 Table Soil Area Long Term Acceptance Rates by Soil Texture, Soil Structure, Percolation Rate and Level Soil Type 0 1 Soil Type, Texture, Structure and Percolation Rate Range USDA Soil Texture Soil Type 1 with more than 35% Rock (>2mm); Soil Types 2-5 with more than 50% Rock (>2mm) Sand, Loamy Sand USDA Soil Structure- Shape -- USDA Soil Structure- Grade 0 (Single Grain) Percolation Rate (MPI) <5 Level 1 1 Minimum 3- foot deep unlined sand filter required 2 Long-term Acceptance Rate (LTAR); Gallons per day per square foot Level 2 1 Level 2N 1 Level 3 1 Level 3N 1 * 2 Minimum 2-foot deep unlined sand filter required Sandy Loam, Loam, Silt Loam PR (Prismatic) BK (Blocky) GR (Granular) 2 (Moderate) 3 (Strong) A 3 3A 4 Sandy Loam, Loam, Silt Loam Sandy Clay Loam, Clay Loam, Silty Clay Loam Sandy Clay Loam, Clay Loam, Silty Clay Loam Sandy Clay, Clay, Silty Clay PR, BK, GR 0 (none) 1 (Weak) Massive PR, BK, GR 2, PR, BK, GR 0 1 Massive PR, BK, GR 2, A Sandy Clay, Clay, Silty Clay PR, BK, GR 0 1 Massive Soil Types 2-4A Platy 1, 2, NOTE: Shaded areas require system design by a professional engineer. 1 levels are defined in Table 6-2b. 2 Unlined sand filters in these soil types shall provide pathogen removal. Design shall conform to section * Higher long-term acceptance rates for Level 3N may be allowed for OWTS required to have a discharge permit, if the capability of the design to achieve a higher long-term acceptance rate can be substantiated.

6 B.3. Renewable Permit a. Effective on or after July 1, 2015 a renewable permit shall be required for any OWTS requiring specified maintenance on a periodic basis to ensure it is continuing to operate per manufacturer specifications. b. OWT systems requiring a renewable permit shall include advanced treatment units, aerobic tanks, dosing siphons and pumps, OWT systems serving commercial structures, cluster OWT systems, and other OWT systems with mechanical and/or electrical components which require periodic maintenance. c. OWT systems that are required to have a renewable permit are exempt from the use permit process C. Renewable permit - Effective on or after July 1, 2015 a renewable permit shall be required for any OWTS requiring specified maintenance on a periodic basis to ensure it is continuing to operate per manufacturer specifications. 1. All OWTS(s) identified in section B.3.b shall be required to have a renewable permit to ensure the system is functioning as specified by the manufacturer. The renewable permit shall show evidence that the system under current contract and is routinely inspected per manufacturer requirements by a licensed inspector. 2. An OWTS that requires a renewable permit shall be maintained and the permit renewed until the system is either abandoned or the Department authorizes the decommissioning or remodel of the OWTS. 3. The Department shall not authorize the removal of a higher level treatment unit unless the OWTS would conform to the requirements for TL1 Systems, including minimum distance setbacks set forth in Table a and STA infiltrative surface to limiting condition set forth in section B.3 and/or Table The Department may revoke a renewable permit for non-compliance with the permit conditions or requirements of these Regulations. 5. The Department may assess penalties for non-renewal of a renewable permit or noncompliance with the terms of the permit. 6. A renewable permit shall specify the following: a. Owner name and contact information b. Property address and parcel id# c. Type, make and model of the component(s) requiring maintenance d. Name and license number of the service provider e. A copy of the contract with the service provider f. Length of service contract g. Required service intervals of the component(s) h. Reporting requirements; and i. Sampling requirements, if applicable