Oversight & Inspection: Water Tank Installation

RPG Resources was contracted by a leading Oil and Natural Gas company to provide quality control and quality assurance inspections and management services for the installation and hydrostatic testing of a Fusion Bond steel panel water storage tank in Weld County, Colorado. The storage tank was erected to hold recycled produced water from oil and gas well production operations. The tank is a 1,666,485-gallon (39,678 barrels) steel bolted structure with an aluminum dome lid. The storage tank was installed on a concrete base within a geotextile-lined earthen-berm containment system. RPG provide qualified inspectors to oversee and manage daily installation, ensure materials and installation practices met design specifics and completed daily environmental and safety site inspections. RPG utilized drones and 360 camera technologies to provide the client with remote construction progress updates and detail inspections reports.

Challenges
The tank must be constructed to meet the AWWA D103-09 design and installation specifications. Particular care had to be taken to protect the powder coated panels from damage during assembly; any coating damage had to be repaired before any testing could be performed. Installation of the tank required systematic process for panel and component installation. Once installation was complete, the tank had to pass a 5-day hydrostatic test to ensure proper installation with no evidence of leaks or deficiencies. Additionally, the tank was constructed during the winter months, which required sealing materials to be kept at specific temperatures to ensure the sealant would properly cure when applied between the tank panels.

Solutions

Installation
Construction progress was managed by RPG’s qualified inspectors. During the active construction phase of the project, inspections were completed daily: involving inspection of materials, equipment, and procedures. Daily inspection findings were summarized within electronic Daily Construction Oversight Reports. Photos and detailed notes of construction progress, materials and equipment were included within each report to create a continuous record. A finalized report was compiled for the client and regulatory agencies.

Technology

Additionally, RPG utilized drone and 360 camera technologies combined with data processing software to provide the client with remote access during construction, updated imagery of the site and as-built maps. The data collected provided accurate gps data, detailed photos and aerial imagery. The software enabled the client to oversee the project’s daily progress remotely and utilize measurement tools to ensure the project was meeting layout specifications.

Hydrostatic Test
Once construction of the produced water storage tank was complete, a fresh water hydrostatic test was conducted to determine the presence and location of any potential leaks or issues with the sealant or bolts. The initial phase of the hydrostatic test included filling the tank with fresh water. The Tank was filled with approximately 43 feet of water at a rate of 420-840 gallons per minute (GPM). The fresh water was mixed with yellow/green leak trace dye in order to make potential leakage visibly obvious.
Monitoring of the produced water storage tank during the initial freshwater fill was completed on an ongoing basis from start to finish. Inspections of the tank and rate of fill were completed hourly over the course of the approximate 39-hour fill. Each inspection noted run time, the tank fill level in inches, any notable leaks, tank fill rate, and total volume filled.
For 5 days following the completion of the tank fill, a hydrostatic test was conducted in order to confirm that no pinholes or leaks were present within the tank walls, sealant, bolts, or flooring. RPG personnel completed one inspection of the produced water storage tank per day during the 5-day hydrostatic test process.

With RPG’s oversight and inspection, the project met all objectives for quality, safety, and performance, ensuring the facility is prepared for long-term operational reliability. The Produced Water Tank construction was successfully completed within the projected timeframe and budget.