Just because people speak Spanish doesn't mean they don't also speak and/or understand some English! It's not a binary do they/don't they situation. Try not make make assumptions about the community you are trying to include. :) Plus, people who literally don't speak or understand any English at all already know they need to bring someone to help them out in daily life if they know they are going somewhere in the primarily English-speaking community.
Doing nothing is worse than the possibility of having a language barrier at the shelter. Language barriers can be overcome with Spanglish, google translate, and a sense of humor, but you won't get that far if people feel ignored or not included in the first place. So do the translations. You can even include a note saying there may not always be a fluent Spanish-speaker on site but you'll do your best, and you can add that you are actively looking for Spanish-speaking volunteers and staff.
Also, in the Spanish-speaking community, English-speakers making effort to speak or engage in Spanish is seen as good thing. Even if you mangle it, people generally appreciate the effort and the good intentions. It's the effort that counts. (in contrast to how many English-speakers in the USA are annoyed or even offended by nonnative speakers who don't know English well)
And of course, the main problem is that your organization is not already including your whole community. But you are aware of it and that's great, so hopefully the translation project will be only the first step towards including everyone!
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M Saucedo
GIS Analyst
Pets for Life
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