Advanced Wastewater Treatment Systems

Transcription

1 Advanced Wastewater Treatment Systems March 25, 2014 George Loomis New England Onsite Wastewater Training URI

2 What we will cover Advanced treatment technologies Demonstration systems Education

3 Where advanced OWTS first started in Rhode Island Foster s Cove Charlestown, RI ca. 1983

4 Summary of nitrogen reducing treatment technologies in Rhode Island Began in early 1980s Requires Rhode Island Technical Review Committee (TRC) approval Over 4,800 system applications approved O&M contract needed Entered into land evidence record Training required OWT 105 Innovative and Alternative Technologies

5 RIDEM OWTS TRC (1996 to present) The technical review committee (TRC) is a group of professionals in the industry Manufacturer makes a claim as to treatment and provides data to satisfy the claim The TRC reviews the application, claims and data in order to approve the technology The TRC may require more data to be collected for analysis TRC makes a recommendation to RIDEM

6 Rhode Island Onsite Wastewater Demo Projects Project Goals - 5 demo projects in 7 communities 58 demonstration systems Replace failed septic systems with innovative technologies Evaluate treatment performance Transfer of knowledge gained to RIDEM Policy / rule revisions VT NH MA CT RI ME Educate practitioners and decision makers

7 Enhanced Wastewater Treatment System 4 Control Panel Regulates timers and switches for effluent pumps in tank, treatment unit or separate pump chamber. 1 Tank Solids settling Water tight Access risers May have pump chamber 2 Treatment Unit Sand, peat, textile filter or other. Single pass for bacteria removal. Recirculating for nitrogen removal 3 Drainfield Often Shallow pressure-dosed or Bottomless sand filter. Time dosed. Final treatment in upper soil layers.

8 Advanced treatment technologies approved in RI ca.1983 ca.1996 ca.2014 RUCK ATUs Single pass sand filters Recirc. sand filters Early textile filters Foam biofilters Shallow narrow pres. drainfields Bottomless sand filters - early Modular peat filters Textile filters Fixed activated sludge systems Bottomless sand filters current Denite upflow filters Trickling filters UV disinfection Soil treatment area renovation technologies N removal systems

9 Several approved N reducing technologies

10 FAST system

11 Orenco Advantex AX-20 - For up to 4 bedrooms - Timed-dosed, recirculating - Telemetry required AX-20

12 Typical use for I&A technologies

13 The conventional system fix 4 feet above grade!

14 Advanced technology solution media filter bottomless sand filter

15 PL

16 Advanced wastewater treatment demonstration repair Site: very small lot, high water table, rocky, sloping. System: Recirculating textile filter with bottomless sand filter.

17 Alternative System Repair Backyard looking towards house served by advanced treatment system repair Bottomless sand filter

18 Alternative Drainfields Shallow narrow pressure-dosed Single family & commercial Bottomless sand filters

19 Example Mixed Use onsite solution Wickford, RI Advanced treatment unit in basement of above historical building serves serves retail at street level and multifamily above, and eliminates direct discharge to coastal waters. Bottomless sand filter provides atgrade drainfield in alley between buildings. Lot line

20 Commercial Cluster 2,700 gpd system serves: Neighborhood restaurant, Duplex apartment, Physician s office, and five-unit strip mall. Shallow narrow drainfield in parking island that is planted to grass

21 1 Multifamily cluster system repair in Chepachet Village 1200 gpd system serving 3 structures 1. Historic society building 2. Two bedroom home 3. Apartment building with six units Each structure has a septic tank and gravity collection in common recirculation tank 2

22 3 6-Unit Apartment Building Recirculation tank collects effluent from the three buildings. Treatment by two recirculating textile filters (blue covered unit) Final dispersal by 7 X 48 foot raised bottomless sand filter

23 Technologies can meet State N standards and satisfy customer expectations for aesthetics

24 System modularity often influences technology selection Complete system heading to ferry for trip to Block Island

25 Relative installation costs System type Ideal sites Difficult sites Conventional $10 15K $20 40K Advanced $16 25K $25 35K Based on a repair system for a 3 bedroom home in 2013 economy Conventional system includes design fee Advanced technologies design fee not included in above ($1.5 to 5K)

26 5) System management, operation and maintenance (O&M) Is not difficult Is not expensive But, IS ESSENTIAL

27 Alternative technology operation and maintenance More system complexity Greater treatment capability Requires more oversight than conventional system Treatment levels directly related to O&M Frequency 1 to 2 visits per year Annual cost $250 to $400 Plus $250 pump out every 3 to 6 years

28 Operation and maintenance activities Technology approvals specify them DEM permits require them Proprietary device companies have contracts Towns may require them under their ordinances Service providers are active Training is available

29 Research based outreach education... Communities Rhode Island NEMO Practitioners and homeowners NEOWTC

30 Training required to design or install BSFs in Rhode Island and Massachusetts (also used in VT and NY) Bottomless sand filter

31 INSP 200 Advanced systems Intensive 2 day course (indoors) Examination 1 week after for inclusion in registration list Prerequisites: OWT 105 INSP 100

32 Thanks for your attention! George Loomis