QA_02-27-2026.pdf

Project : ID FS NEZPR117 221(1), National Forest System Road 221 Rehabilitation

# General Technical Question Answer Date

1 X

Can you provide clarity on the control sheets D1 and D2? You are giving point numbers up to C25, but there is some confusion in how to find the control on the ground. Typically, plans will show the control points along the horizontal alignment.

Are you able to provide more detail on where they go or give a mile marker to their locations? For example, on Sheet G.1, the pipe is called out (MP 8.638 CP 25101).

Something like that and detailing location from centerline (15’ RT) would help as of right now it’s difficult to locate.

Bid as shown per the plans and specifications, the Government has provided the Northing/ Easting and

Lat/Long coordinates to establish the control locations.

2/12/26

2 X

Regarding the Micro surfacing bid item in the contract. The contract language refers to ISSA A-143 for specifications on a portion of the contract. ISSA A-143 are not specifications per se, but a guideline to develop contact specific specifications.

This project is specified with TYPE II aggregate. NF System Road 221 is a mountainous area with low traffic volumes. The type II gradation being specified is a smaller aggregate size typically used for residential, parking lots, bike lanes etc. creating a smoother surface. Type III aggregate is a coarse gradation, more aggressive for skid resistance, a higher application rate that will provide better life cycle costs and duration. Along the same lines, ISSA A-143 indicates an application rate for type II of

10-20 lbs. of aggregate per square yard. Since the micro surfacing is bid by the square yard and not the lbs. of aggregate, having a range of 10-20 lbs. incentives the contractor to bid the least amount of aggregate per square yard to obtain the lowest cost per square yard. 10 lbs. of type II aggregate per square yard in this environment will not have the life cycle costs of a type III aggregate at a higher application rate.

WFL currently has a MATOC entitled Western Region Pavement Preservation.

Specifications for type II or III aggregate is much higher and the range is much less based on lbs. per square yard. My suggestion for creating a micro surfacing product that will provide the best overall value for the taxpayer and US Forest Service is using a type III gradation with an application rate of 25-30 lbs. of dry aggregate. If the type

II is the preference, then the application rate should be 17-22 lbs. especially using the micro surfacing to cover the new chip seal application.

Provide Microsurfacing, Type II according to the solicitation. Submit proposed application rates according to Subsection

409.04(g).

2/27/26

Check General or Technical

3 X

Along the same lines of specifications. ISSA A-143 does not specify the use of on type of equipment application over another. However, this project is 28 miles in length.

The micro surfacing industry has two primary uses of equipment. A continuous application and individual mixers. The continuous application is similar to HMA paving and chip seal. Meaning the process from the start continuously moves forward applying the micro surfacing. As long as micro surfacing material is supplied to the continuous paver, the process continuously moves and produces micro surfacing. With the individual mixers, each time a individual mixing unit empties the materials, that unit has to stop, remove the spreader box and another unit that is fully loaded begins the process. This creates a transverse joint every 500-600 feet.

This would create approximately 500 transverse construction joints for the final riding surface. A continuous operation could pave for 1-3 miles without creating a transverse joint. Along with the advantages using a continuous paving operation, the continuous operation uses (1) one paving machine. Individual mixers would use 3-4 mixing units. Each unit whether using on or the other need to be calibrated prior to beginning construction. Like a batch plant on wheels, this process is critical to the mix design, and the job mix formula for the micro surfacing materials. It is very difficult to have each machine placing the exact same proportions of aggregate, emulsified asphalt, mineral filler, water and other additives the same. Using (1) paving machine eliminates this challenge. Industry standards require applications that are miles of continuous work to be completed with he continuous method and will not allow individual mixing machines. For the reasons mentioned, specifically requiring the continuous method will provide a much better overall project.

Use equipment that conforms to

Subsection 409.05.

2/27/26

4 X

ISSA A-143 guidelines suggest using a scalping screen prior to being loaded into the mixing unit. This eliminates any oversized aggregate that may be inadvertently loaded from the stockpiled aggregate on the job site. This could create drag marks in the final surface and contaminate aggregate on the surface. Best practice is to require screening the finished aggregate prior to loading into the paving unit.

Use equipment conforming to Subsection

409.05.

2/27/26

5 X Please clarify if the micro surfacing final cured product will require rolling prior to allowing traffic to drive unrestricted on the new micro surfacing.

See Subsection 409.10 for rolling, curing, and opening to traffic. Rolling the cured

Microsurfacing is not required.

2/27/26