Slew and slough are often interchanged. FYI ... slew is the past tense of to slay. Slough is a swampy area. So north of the cache is a slough, but if you happen to see a knight defeating a dragon, please let me know and I'll change this to a slew.
Please note, these country roads are used and maintained by the Oil and Gas industry and the farmers. Please respect that and drive carefully.