Part seven of this industrial stormwater blog series looks at an interesting plot of land for the Tesoro Corporation. The Tesoro facility required a stormwater plan because of its unique location on a narrow peninsula in the Salish Sea. Tesoro worked with Tulsa Engineering Alliance to engineer an oil/water separator with an accompanying package stormwater pump station from Romtec Utilities.
The pump station was fairly straightforward for an industrial job. Collected stormwater from the facility is drained into an oil/water separator first. After oil separation, the water drains into the Romtec Utilities pump station where it is pumped to the Crown Sewer Treatment Plant. This preliminary treatment ensures consistent water chemistry, eliminating a major concern for lift station engineering.
The station itself is less than 8 feet deep and includes two, Ebara submersible pumps in a duplex configuration. The system valves were contained within the wet well, and a drop bowl was included to reduce turbulence in such a small sump. Level sensing was engineered with NOLTA floats, which are suited for small containers. The pedestrian rated hatch offered easy access to the in-well system components for inspection and maintenance. This design is uncomplicated because the water chemistry and flow rates are so consistent.
The interesting aspect about this pump station is the unique location. The Tesoro facility is fundamentally a transfer site for offloading refined fuels from cargo ships into large holding tanks. The fuel is then dispersed for distribution from these tanks. The facility is located on a peninsula that is less than 150-feet-wide, with shoreline into the Salish Sea on both sides. Containing the total stormwater from the facility was an essential environmental consideration.
The seven holding tanks, ranging from about 20 to 80 feet in diameter, are surrounded by concrete containment walls and are further divided into drainage sections by concrete curbs. This method of drainage ensures that each section drains to its own catch basin, preventing any one basin from being overcome and flooding. This level of containment is necessary to prevent any significant amount of stormwater from reaching a natural habitat.
Romtec Utilities supplied Tulsa Engineering with only the structural and mechanical components in the system package. Tesoro preferred to use its own staff to implement station controls and electrical engineering. The ability of Romtec Utilities to customize its supply package to the customer’s specifications is really an asset, even on a small system such as this project.
With Romtec Utilities, Tesoro was able to purchase an affordable way to manage the stormwater at this transfer site. Oil and gas companies like Tesoro are working hard to manage their environmental impact, and purchasing a reliable, affordable, and customized Romtec Utilities package lift station is an excellent solution for implementing and managing a stormwater plan.
Next week, we will look at one of the largest stormwater systems ever designed by Romtec Utilities.