Border Deal Exists to Go into Mexico
Using Environmental Emergency which this would qualify as.
Based on the La Paz Agreement, the U.S. and Mexico support each other during incidents that may occur along the shared international borders. U.S and Mexican personnel and equipment may cross the borders to respond to border environmental emergencies. EPA and local responders also work with Mexican counterparts to perform joint exercises of contingency plans and discuss preparedness and response issues. These preparedness activities as well as responses to real world incidents necessitate liability coverage and expediting cross-border travel of personnel and equipment for both countries.
https://www.epa.gov/border2020/emergency-response-policy-forum
They might even dare I say it….PAY FOR IT
La Paz agrrement since 1983. Updated every year. 60 day out clause by either country. Has not been terminated and no notice given.