Sign S32-1 “Litter Removal” as specified by the California Department of Transportation (Caltrans) for use with the <i><a href="https://en.wikipedia.org/wiki/California_Manual_on_Uniform_Traffic_Control_Devices" class="extiw" title="w:California Manual on Uniform Traffic Control Devices">California Manual on Uniform Traffic Control Devices</a></i> as part of Caltrans’ <a href="https://en.wikipedia.org/wiki/Adopt-a-Highway" class="extiw" title="w:Adopt-a-Highway">Adopt-A-Highway</a> program.
California Department of Transportation
<a rel="nofollow" class="external text" href="https://dot.ca.gov/-/media/dot-media/programs/safety-programs/documents/signs/s/s32-1-a11y.pdf">Litter Removal</a>, <a rel="nofollow" class="external text" href="http://adopt-a-highway.dot.ca.gov/Sponsor_FAQs_6-3-10.pdf">Adopt-A-Highway Sponsor FAQs</a>