WNP Projects 1/4 are partially completed nuclear projects located on the Hanford Site on approximately 972 acres. The sites are one and one-half miles east of the Columbia Generating Station (location map).

In May 1974 the application for the WNP-1/4 projects was filed by the Washington Public Power Supply System (now Energy Northwest) and hearings were held during early to mid-1974 and a Site Certification Agreement (SCA) for the combined projects was signed by the Governor on August 8, 1975.

Construction of WNP-1 was halted in 1982. In May 1994 the Energy Northwest board of directors adopted a resolution terminating WNP-1.

In June 1995, EFSEC approved a Site Restoration Plan for WNP-1 that deferred demolition. In the interim, Energy Northwest has carried out a minimal level of maintenance and security control at the WNP-1 project site.
In early 2003 Energy Northwest, the US Dept. of Energy - Richland Office (USDOE), the Bonneville Power Administration (BPA) and the State of Washington agreed on a WNP-1/4 Site Restoration and Funding Plan (also known as the "Four Party Agreement"). The Plan called for certain "health, safety and environmental protection"; commencement of final site restoration by 2026, BPA funding of the site restoration; and $3.5 million from BPA for offsite Environmental mitigation.

In December 2014 EFSEC approved an amendment to the SCA to address completion of the near term health, safety and environmental protection activities set out in the Site Restoration Plan. The amended SCA, required by the Four Party Agreement, includes only those requirements deemed necessary to complete restoration activities.

For a number of years following the termination of WNP-1/4 the various buildings and facilities were leased prior to final restoration of the site. The leasing program is now ending. Areas within the original site boundaries of WNP-1/4 designated for reuse are referred to as the Industrial Development Center (IDC). Energy Northwest has entered the restoration phase of the project, per the terms of the restoration agreement signed by Energy Northwest, the Bonneville Power Administration and the USDOE. The current phase of restoration is scheduled for completion in June 2018. The final phase of restoration is scheduled to begin in 2020, with completion planned in 2023.

In 2013 the USDOE and Energy Northwest determined that the existing water supply infrastructure at the IDC based on withdrawals from two groundwater wells, was inadequate. In order to support reuse of the site the USDOE, in its role as landowner, submitted an application to Ecology for a surface water right from the Columbia River on October 31, 2013. Ecology signed the water right on January 8, 2015.

On July 1, 2017, Energy Northwest extended its lease for the WNP-1/4 site with USDOE. The new agreement contains options for additional 10-year lease extensions, but the lease will expire no later than January, 2052.