Following are selected excerpts and links to full reviews of key technical documents produced by the sponsor of the proposed dam, the Chehalis River Basin Flood Control Zone District (FCZD). The reviews were produced by Quinault Indian Nation technical consultants.
“There are several mechanisms that could drive a dam break scenario, two of which are of particular concern. . . The first is landsliding within the reservoir area that could send large displacement waves over the dam. The second is a deep subduction earthquake.”
“(T)he reservoir area is extremely prone to landsliding due to the weak bedrock, steep slopes, and high precipitation. Reservoirs with large variation in water levels and rapid drawdowns are prone to trigger large landslides, yet the analysis evaluating these events is incomplete and did not consider or address large displacement waves that would be generated if a large landslide occurred while the reservoir was retaining water.”
“The ability of the proposed FRE facility to withstand a deep subduction earthquake, and/or a shallow earthquake of the Doty fault, has not been incorporated into the design.”
“As presented, the information provided to public and decision-makers regarding the risk of dam overtopping and failure is not fully disclosed nor accurately depicted given that the proposed FRE facility, as presented in the DEISs and as acknowledged in the Technical Memo, has not yet been designed to meet all applicable dam safety standards.”
“Given the flawed assumptions of the VMP, it fails to recognize the pernicious effect of landslides, erosion and mass wasting throughout the reservoir due to loss of hillslope root cohesion and the inability to establish and sustain deep-rooted trees both initially before the first inundation event and after repeated inundation events.”
“The VMP fails to acknowledge or provide any provision for response to the likelihood of substantial vegetation mortality, particularly adjacent to the river channel, following over 30 days of submergence under 200 feet of water.”
“The VMP fails to minimize or offer a viable strategy to mitigate the consequent significant impacts on water quality within the Chehalis River, particular increases in water temperature due to the loss of channel shade throughout the riparian zone of the proposed reservoir.
“The VMP also fails to present a viable strategy to reduce significant water quality impacts through the introduction of vast quantities of fine sediment input into the river as a result of the loss of root cohesion, slope instability, and landslides.”
“The construction phase fish passage is needed for passing target species and life stages throughout the duration of the construction period. Construction is anticipated to last three to five years and fish passage must be provided during the entirety of this period.”
“. . .the facility combined with the velocity barrier is likely to act as a complete or near complete blockage to upstream migrating spring Chinook. This would pose a high, significant risk to spring Chinook in the upper Chehalis Basin.”
“. . .technical memoranda appear to assume that downstream passage impacts would be trivial, and therefore are essentially ignored in discussions about expected impact levels. . . the DEIS assumed a downstream passage survival of 85 percent during construction (DEIS, p.E3-5), which is a significant adverse effect. No explanation is given anywhere in the technical memoranda for why this matter is apparently being ignored in advancing the facility design for the construction phase.”
“Although the Technical Memo does provide information on potential alternative methods to avoid and minimize impacts to wetlands, the memo fails to justify its conclusion that the levee construction alternatives presented could be used to completely avoid wetland impacts. The memo considers only direct impacts, ignoring the potential for indirect or cumulative impacts.”
“The analysis presented in the Technical Memo offers regulatory decision makers no basis by which to definitively determine that any of the proposed approaches would result in a less damaging alternative than that presented in the NEPA and SEPA DEISs.”
“. . .we conclude that the analysis presented to date regarding the proposed quarries fails to disclose or continues to significantly under-represent and mislead the public and decision makers regarding potential impacts to the environment and does not meet the adequacy standards of SEPA and NEPA environmental review. As a result, granting a permit for the FRE project, as proposed, would be based on arbitrary factors that are inconsistent with the statutory regulatory processes for a project of this scale, intensity, and context.”
