H.R. 10318, the Pacific Minerals Economic Security Act, amends federal law to regulate seabed mining on the ocean floor near U.S. Pacific territories and ensure those territories benefit economically from such activities. The bill applies to Guam, American Samoa, and the Northern Mariana Islands, requiring mining companies to post substantial security bonds before operating and prohibiting the government from waiving fees or royalties owed by mining operators. Starting in fiscal year 2027, the law would split all revenue from seabed mining leases fifty-fifty between the U.S. Treasury and the affected Pacific territories, with payments distributed based on proximity to mining sites and designated for coastal restoration, infrastructure development, environmental protection, or debt reduction. The bill also requires the Interior Department to conduct a study within one year on environmental mitigation methods for seabed mining and notifies territorial governors about mining proposals so they can review and comment on potential environmental impacts.