3Kings Water Treatment Plant
In 2014 Park City was issued Utah Discharge Elimination Systems (UPDES) permits for the discharge of water draining from the Judge and Spiro mine tunnels into McLeod and Silver Creeks. Water from both tunnels exceeds stream water quality parameters identified in these permits.
Due to the cost and complexity of bringing this water into compliance with UPDES permits, a Stipulated Compliance Order (SCO) was entered into between the Utah Division of Water Quality and Park City. The SCO requires that Park City develop and implement a plan to bring discharge into compliance by the year 2024 for the Judge Tunnel and 2033 for the Spiro Tunnel.
In addition, the existing Spiro Water Treatment Plant is aging and will soon need significant investment to keep it operational. While the existing plant consistently produces high quality drinking water, it cannot treat to certain parameters in the UPDES permits, and it lacks capacity to maximize available water from the combined Judge and Spiro Tunnel water sources.
This project will demolish the existing Spiro Water Treatment Plant and construct the new 3Kings Water Treatment Facility in order to:
- Improve water quality and reliability
- Increase water treatment capacity to maximize use of available water from Judge and Spiro Tunnels
- Increase overall City water supply resiliency and peak day capacity
- Meet UPDES permits and Stipulated Compliance Order (SCO) for Judge and Spiro Tunnel water discharges
3Kings Water Treatment Facility
The redevelopment of the Spiro Water Treatment Plant will include:
- New 3Kings Water Treatment Facility
- 3,000 gpm (4.1 mgd) Mining-Influenced-Water treatment capacity
- 1,500 gpm (2 mgd) Thiriot Springs water treatment capacity
- 48,000 sq ft total facility building footprint
- Golf Course pond improvements
- enhance water quality and storage capacity
- Associated off-site utility improvements
- New/ relocated Golf Maintenance Building
Golf Maintenance Building
Due to space requirements to meet treatment needs at the new 3Kings Water Treatment Facility, the existing golf maintenance facility will need to be demolished and relocated. Public Utilities has worked with the Golf division to locate a new facility on the golf course with minimal impact to the course and driving range.
The new Golf Maintenance Building will include:
- 1,900 sq ft Administrative Office and Maintenance Building
- Golf Maintenance office
- Multipurpose room (break/lunch room, conference room, training room)
- Restrooms and lockers
- Equipment repair area
- Tools and parts storage
- 4,300 sq ft Tempered Equipment Storage Balding
- Equipment and hand tool storage with minimal heating
- 1,000 sq ft Covered Wash/ Fueling Area
- 1,000 sq ft Bulk Material Storage (sand, mulch, soil)
What is Mining-Influenced-Water?
During the mining period in Park City’s history, drainage tunnels were constructed at the lower elevations of the mine works to keep water within the mountain from interfering with the mining operations. These drainage tunnels, which contain trace metals from the natural soils and mining operations, discharged directly to the environment. Over the course of Park City’s history, these waters have been used for various purposes such as drinking water, irrigation, and snowmaking. The water which exits existing mine tunnel entrances (portals) are referred to as Mining-Influenced-Water (MIW).
Why Treat Mining-Influenced-Water ?
Metals in waste streams don't naturally degrade and are toxic to aquatic life, even at low concentrations. As part of the EPA’s Clean Water Act, it has established that cleanup of mining-influenced-waters, such as those being discharged from the tunnels, is a significant environmental benefit. In 2014 the Utah Division of Water Quality (DWQ) and Park City entered into a Stipulated Compliance Order (SCO) which contained major milestones for treatment compliance and requirements on pollutant loadings related to the water discharges from the Judge and Spiro mine tunnels. Non-compliance with the terms of the SCO can lead to:
fines and operations interference from the State of Utah Division of Water Quality and the EPA:
continued stream degradation
Characteristics of M-I-W Treatment Design
Water treatment design is a process in which the raw water is analyzed and, based on the receiving water characteristics (stream designation by the DWQ) and the discharge requirements for the treated effluent (water to be discharged from the plant), the treatment process is established. The design is highly site specific and focuses on treatment efficiency, reliability, cost-effectiveness, and minimalizing such items as energy use, traffic impacts, maintenance, and personnel.
Characteristics of the tunnel water must be taken into consideration in terms of physical, chemical and biological characteristic. Sizing of the M-I-W treatment plant depends upon the flows collected within each drainage tunnel. Tunnel flows change from year to year and vary significantly from season to season. The new water treatment plant process has been developed through substantial studies, which included a year-long pilot-scale study to establish the treatment process and prove its effectiveness in removing metals in the tunnel raw water and a thorough evaluation of life-cycle cost and benefit.
The selected process is considered a multi-barrier approach and includes pre-oxidation, rapid mix/flocculation/ sedimentation (to remove specific particulate metals though precipitation), granular media filtration (to further remove iron and manganese from the water which may cause aesthetic water quality problems such as reddish and/or blackish staining of sinks/bathtubs or laundry), post-filter adsorption (where specific medias are used to remove targeted dissolved metals), and disinfection (for drinking water use).