Despite an extremely tight deadline, M&A helps APS relocate a major well field and assists in settling a land-lease dispute.
Client: Arizona Public Service (APS)- Time frame: 2005–present
- Location: Cholla Power Plant, Joseph City, Arizona
APS retained M&A when a long-term land lease was terminated, threatening the well field where over half of the water supply wells for the Cholla Power Plant were located. To serve the plant’s annual water demand of about 16,000 AFY, which would soon increase to 18,000 AFY, APS was under a critical timeline of less than 9 months to shift its production to existing or new wells located on its property. After achieving this milestone, M&A proceeded to help APS expand the well field and develop redundancy to provide reliable back-up operations. In addition, the monitoring network — also largely lost because of the lease termination — was replaced to the extent possible on land owned by the power facility. Our team consisted of in-house hydrogeologists and water-policy experts, and an engineering / construction and drilling subcontractor.
An exploration program was launched to identify locations where groundwater quantity and quality conditions were most favorable for installing new production wells. Boreholes were logged using acoustic and optical televiewer tools to assess the distribution and density of fractures within the sandstone aquifer.
Based on the results of this program, 11 new production wells were installed and two existing wells were modified to meet demand requirements. M&A provided field oversight for the installation and testing of these wells. In many cases, downhole explosives were deployed to enhance fracture connectivity, resulting in sustainable yields exceeding 3,000 gpm in some wells.
M&A also selected and managed the engineering / construction contractors who installed all the pipeline, wellhead, and pumping infrastructure under extremely tight deadlines.
To support land-condemnation negotiations, APS needed to know the value of the leased land where its wells were located relative to the landowner’s property. M&A assembled technical, regulatory, and economic data sets, integrating the results into a GIS platform to display various aquifer characteristics in relation to property ownership. The analysis indicated that conditions for groundwater development were less favorable on much of the leased land than they were on the leaser’s adjacent holdings. This information helped APS negotiate land values, enabling the parties to reach a settlement.
M&A installed about 20 wells in the power plant vicinity to monitor water level and water quality conditions. The wells were completed in the both shallow alluvial aquifer and the deeper sandstone aquifer; many were equipped with data loggers and pressure transducers to continuously monitor the aquifers’ response to pumping and streamflow runoff. We also oversaw sampling operations that were designed to assess water-quality relationships and then interpreted the results.
As part of this project, M&A developed a groundwater flow model. Our objective was to simulate drawdown impacts from historical pumping and evaluate the potential for increasing production capacity. The results will also be used to understand the relationship between surface water and groundwater resources.
In anticipation of future adjudication proceedings, M&A provides technical support to characterize and monitor the relationship between pumping from the sandstone aquifer and surface water resources.
Outcome
M&A was able to meet the aggressive deadline, successfully shifting the plant’s water production to the new wells and expanding capacity without interrupting plant operations. We also supported APS and its water attorneys in reaching a settlement with the landowner.
In recognition of a successful project, M&A was selected as Cholla Power Plant’s “Supplier of the Year” for 2008. We were acknowledged at an awards banquet on May 21, 2009, at the Heard Museum in Phoenix, where APS honored ten companies as the “best-of the-best.” According to Ron Trafzer, Director of Supply Chain Management for APS, “the ... awards are an opportunity for our company to honor those who continue to bring innovative ideas and solutions to enable us to achieve our goals.” APS works with more than 4,000 suppliers each year. The winners “excelled at meeting APS’ expectations of achieving the best total cost-of-ownership value, including delivery, quality, cost, account management, and safety.”
Acronyms & Abbreviations
