O38 Email from Nov 13 2025 to Dec 9 2025 between Mr Kleinberg and Mr Seele

Mark Seel Associate Principal / Vice President LANGAN Direct: 973.560.4986 Mobile: 724.263.2179 ile Sharing Li www.langan.com Technical Excellence e Practical Experience e Client Responsiveness NEW JERSEY NEWYORK CONNECTICUT MASSACHUSETTS PENNSYLVANIA VIRGINIA WASHINGTON, DC OHIO ILLINOIS NORTH CAROLINA TENNESSEE FLORIDA TEXAS ARIZONA COLORADO UTAH WASHINGTON OREGON NEVADA CALIFOR NIA ATHENS CALGARY DUBAI LONDON PANAMA From: Kleinberg, Sam <SKleinbere@cmeusal.com> Sent: Tuesday, December 2, 2025 5:09 PM To: Mark Seel <mseel@langan.com>; pani n) mail.com Cc: MacNeill, Ryan <rmacneill@cmeusal com>; Rizzo, Jordan <jrizzo@cmeusal .com>; Hernandez, Nelson <NHernandez@cmeusai.com>; Mazier, Alejandra <AMazier@cmeusal.com> Subject: FW: WEHI Thank you Mark for your quick reply,; Please see our comments below in red: From: Mark Seel <mseel@Langan.com> Sent: Tuesday, December 2, 2025 1:24 PM To: Kleinberg, Sam <SKleinberg@cmeusai.com>; pandersonpe@gmail.com Ce: Hernandez, Nelson <NHernandez@cmeusal.com>; MacNeill, Ryan <rmacneill@cmeusal.com>; Rizzo, Jordan <jrizzo@cmeusal.com>; Mazier, Alejandra <AMazier@cmeusal.com> Subject: RE: WEHI This Message is from an external sender. Sam, A couple observations and thoughts: 1. The infinite slope case assumes water and failure surface parallel to the ground surface and assumes uniform surface and subsurface conditions. The infinite slope case is therefore an approximation because the ideal case doesn't exist (i.e., slopes are not exceptionally long or uniform). The infinite slope case is also a very shallow condition to validate the proportion of depth to length, as opposed to deeper seated potential failures. CME Response: We understand the limitations but maintain our recommendation that the stability evaluation consider the potential impact