POSTING NOTICE. Supplements to this title are numbered consecutively. Check the last transmittal received for this title to see that the above supplement number is in sequence. If not, order intervening supplement at once. Do not post this supplement until the missing one(s) is received and posted. After posting, retain this transmittal until the next supplement to this title is received. Place it at the front of the title.

Number of Sheets

Page Code Superseded New

2.22--1 -- 1

Digest: Adds guidance for determining that assist vehicles are needed on certain road grades.

TED STUBBLEFIELD

Forest Supervisor

December 10, 1991

2.22--1

2.22 - Location Marking

2. Location Notes. The maximum practical adverse grade for log hauling on gravel surfaced roads, without a means of positive assistance, is 16%. Log hauling on adverse grades under 12% on these roads usually does not require positive assistance. Region Six limits grades on Traffic Service Level D Roads to a maximum of 15% through switchbacks, steeper grades require positive assistance. At the present time Washington State Logging Safety Standards requires a positive means of assistance when grades exceed 20%.

Log trucks hauling on gravel surfaced roads that have adverse grades between 12% and 16% may need positive assistance. Log trucks hauling on favorable grades exceeding 16% may also need positive assistance. Some of the factors that would affect the need for positive assistance are: surfacing type and/or compaction; season of haul; insloping/outsloping; alignment, especially around switchbacks of less than 100' radius, or reverse curves; inadequate area to get trucks up to minimum sustained speed; logging equipment movement disturbing the compacted surface.

Construction of roads to the maximum limits of some construction tolerances might cause a need for positive assistance where it otherwise is unnecessary. In situations where this might occur the locator should advise the designer to specify a tolerance that will prevent this from happening, or recommend including positive assistance in the timber sale appraisal.

When the locater determines that positive assistance will be needed, or is likely to be needed, this information will be fully documented in the Field Location Report and also furnished to the timber sale appraiser. The Road Management Objectives Record will also be updated at this time to reflect the need for assist in the "other" block.