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Day & Zimmermann is the nation’s leading provider of maintenance and modifications services to the U.S. power industry helping coal-fired and natural gas plant owners generate power.

What We Do

Maintenance & Modifications

Our Total Accountability Model provides a single point of contact driving accountability across safety, human performance, cost, schedule, quality, and resource supply.

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Projects & Construction

Our teams are familiar with, and have worked on, virtually every primary and secondary plant system in both outage and non-outage environments, routinely executing critical and near-critical path work scopes.

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Welding Services

Our experienced, highly qualified welders perform everything from large turn-key projects to small emergent scopes for nuclear and fossil utilities nationwide.

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Valve Services

Our full-scope capabilities are an integrated approach, including valve and operator testing, repair, and refurbishment.

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From scaffolding design to decontamination and storage, our planning and implementation process is designed to reduce or consolidate scaffold use.

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Fossil Fuels

Approximately 66% of all US energy is generated by fossil fuels.

Emissions from coal-based electricity generation have decreased by more than 40% since the 1970s while coal use in the U.S. has tripled.

The coal industry provides more than $1 billion in total U.S. labor income.

Success Stories

MidAmerican Neal SFC and DFC Install

Submerged Flight & Dry Flight Conveyor Installation

Day & Zimmermann provided supervision, craft labor, and construction services to install a United Conveyor-supplied Submerged Flight Conveyor (SFC) system and Dry Flight Conveyors (DFC) at MidAmerican’s Neal Energy Center Unit 3 during the spring 2018 outage.

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Featured Story

Efficient Removal Technique Implemented for Feedwater Heater Replacements

Using engineering and rigging expertise, D&Z successfully removed and replaced two feedwater heaters with only inches to spare.

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Featured Story

Combined-Cycle Power Plant Construction Completion & Commissioning

D&Z team performed final construction and commissioning of a 440 MW combined-cycle gas plant set to serve 25,000 customers in the Pacific Northwest, meeting strict, federally mandated first-fire date, safely and on-budget.

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