12FPC122R0004F Questions.pdf

12FPC122R0004F Questions

• Do you have any mapping showing the survey location?

Sheridian County Kansas 21-T10S-R26W

• Also, has there been any prior archaeological assessments or research on what kinds of archaeological features may be anticipated?

Map key: light blue line-project area; yellow-APE; Broken red line-terrace; purple-site location; hatched yellow-previous survey

Site To geophy survey 14SD00427

Site description: Extensive chipped stone artifact scatter located on the loess-mantled upland surface on the west side of Turner Draw. Site parallels scarp of upland edge overlooking draw. Range of early, middle and late stage reduction debitage, but almost no formal tools this suggests the site has been heavily impacted by local artifact collectors. Six small shovel tests indicate the site is confined to the surface soil, 0-30 cm below ground surface.

Artifacts observed but not collected: 100s of artifacts observed. Chipped stone: core, angular debris, flakes.

Artifacts collected: 100 chipped stone artifacts: 93 flakes; 2 angular debris; 4 flake tools; 1 biface.

• Is there any flexibility with the methods? For instance, is GPR required for the entire 20 acres?

Magnetometry is ok for the 20 acre survey

• What are the smallest size archeological features that should be found with this study (affects the question above)?

Unknown as that’s why we need a survey. Possibly postholes or small refuse pits o This will affect the expected survey frequency (i.e. how much coverage is expected with GPR for example – on a 10’ x 10’ grid? 5’ x 5’?)?

• The most efficient way to cover 20-acres would be using a trailer mounted geophysical instrument package towed by a UTV. Would a UTV vehicle be allowed in the survey area and is the site open and unobstructed (i.e. field) that a UTV could drive along parallel lines? Or must all geophysical surveying be done on foot and hand carrying the instrumentation?

Ped survey with instruments was planned for but UTV survey is possible if the contractor is equipped

• 2) Are there specific geophysical acquisition parameters that are preferred for each requested method, such as line spacing, sampling density, etc?

Standard spacing is fine

• What are the primary archeological targets of interest (i.e. burial sites, encampments, buried structures, etc.)?

Any intact subplow zone features, esp burial. We want to rule out and or define Possible NRHP eligible deposits.

• Is the full 20-acre site required to be surveyed using all the requested methods (Ground penetrating radar, Magnetics and Resistivity) or is it acceptable to propose one or two primary method(s) to cover the entire site, with the other method(s) used to perform detailed surveys in areas of interest defined in the primary survey?

Magnetics over the 20 ac would be great

• The effective application of ground penetrating radar (GPR) is very site-specific. The ground surface in the area to be surveyed must be relatively smooth to provide direct ground coupling of the GPR antenna. Additionally, the depth of investigation of GPR is directly related to the soil conductivity. In areas with relatively conductive soils, such as soils with high clay content, the effective depth of penetration of GPR can be severely limited. Can any information be provided in regard to ground surface conditions and soil type at the site?

Probably not good for GPR

• For resistivity surveying, there are different geophysical instruments that can be used to measure the electrical properties of the soils, using either direct current methods and electromagnetics (EM) methods. Direct-current methods such as electrical resistivity tomography require driving metal electrodes 6 inches into the ground at regular spacings to directly couple with the soil. While minimally invasive, this could potentially damage shallowly buried artefacts. The EM approach is preferred as it is totally non-invasive (inductively ground coupled) and is more efficient at covering large survey areas. EM measures soil conductivity, which is the inverse of resistivity.

Therefore, we would like to confirm that the EM method is acceptable for the requested resistivity survey?

EM is possible