When a goldmine operator needed power for a leak detection system at a tailings pond

Background

PCE Pacific, Inc., and SunWize partnered to provide a power solution to a goldmine operator for a leak detection system at a tailings pond. The equipment to be powered consisted of I/O and SCADA radios in a high US desert environment at approximately 5000-6000’ above sea level.

Challenge

From the main mine processing area, a 6,000’ long, 8” diameter plastic pipe runs to a tailings pond. The tailings pond does not have a direct line of sight to the process area due to the berm around it and it is situated at a lower elevation. The plastic pipe runs alongside the tailings pond access road and is buried at the entrance to the causeway to allow vehicle access to the tailings pond causeway. At the bottom of the causeway is a large gasoline powered pump on wheels with a suction line into the tailing pond.

There were three concerns:

Main processing area cannot see if the plastic pipe ruptures because of the berm. Hundreds of gallons of water could potentially be released due to a broken pipe and could be subject to a fine by the US Bureau of Land Management (BLM).

After the pump is manually started, the pump has to be monitored at the pump location.

There is no power available along the plastic pipe route to the pond except at the main processing end.

After an on-site visit, PCE and the customer mutually decided to pursue a solution using DP sensors and a radio based I/O SCADA system to monitor the pump & pipe operation. This solution could be implemented in a short timeframe and could be moved and reused as needed for other projects of a similar nature in keeping with the temporary usage timeframe. The plastic pipe could be monitored and sectionalized quickly for any rupture or leak problems as well as monitor the pump output. The three sensors were located in the process area, at the top of the causeway, and at the bottom of the causeway close to the pump.

Solution

Two SunWize Power Stations provide 24 VDC power to the causeway DP sensors and radios. Using solar for power was critical to making this solution possible. The solar array is mounted on the same antenna support structure that supports the NEMA-4 radio enclosure housing the radio, wiring terminations, etc. The battery is located at the base of this same antenna support structure and sized for 10 days of no sun. A radio site survey was performed to verify calculated radio path profiles, to confirm the line of sight, GPS readings, and 1st Fresnel zone clearances. Results of the site survey were used to calculate the solar array loading and battery capacity. PCE pre-programmed and tested the radios as a system prior to the customer installation.