Cultural Resources and Structural Rehabilitation

1. Cultural Resources and Structural Rehabilitation Your NRCS Responsibilities

2. Rehab and NRCS • NRCS has responded to the national need to rehabilitate dams to ensure public safety and extend the useful life of valuable public works. • NRCS must also take cultural resources into account. • A cultural resources specialist is available for oversight.

3. The structure itself may be an historic property Much of the area is disturbed Much of the APE (area of potential effect) is on disturbed ground PSA (posts settlement alluvium) is usually abundant The structure itself is not an historic property Often, most of the area has little disturbance Usually the APE has little disturbance. PSA is often less of a factor Rehab Differs from New Construction for Cultural Resources REHAB NEW CONSTRUCTION

4. Is the Structure More than 50 Years Old? • To be taken into account under Federal cultural resource law, the cultural resource usually must be more than 50 years of age. • Structures less than 50 years old, need not be considered (although there may be other cultural resources present that need to be considered). SCS designed CCC structure built in 1935

5. Only significant sites need to be taken into account Criteria of Signficance • Associated with important events • Associated with important people • Is distinctive in design or construction • Potentially contains important data

6. Is an old structure significant? • Common reasons old structures are significant involve associations with important events or the distinctiveness of design or construction. • For example, the first watershed in a conservation program, or an early example of employing a new technology. A structure built in the 1930's

7. The structure must have integrity to be significant • The structure must have integrity of location, setting, design, materials, workmanship, and feelings and association. This dam has been so choked with sediment that it lacks integrity

8. Common reasons old structures lack integrity • The setting may have radically changed, e.g. from rural to urban. • The structure may have been updated with repairs or new construction. • The structure may have been breached or filled with sediment. Structures that were once rural may now be urban housing areas

9. If the structure to be rehabilitated is a significant cultural resource: • And you do not have an effect on those attributes that make it significant, you do not have a cultural resource problem. • If you do have an effect, the agency will have to take it into account. This means weighing the cultural resource against other values of the undertaking and going through a consultation process.

10. Rehabilitation may have an effect on nearby cultural resources Common disturbance factors • New borrow areas • Dam enlargement • Constructing access roads • Altering auxiliary spillways • Removing existing houses • Disposal of sediment

11. Areas that don’t need surveying • Areas covered by post settlement alluvium (PSA) • Recently disturbed ground • Areas already archeologically surveyed • Steep areas

12. Post Settlement Alluvium (PSA) • PSA is recent over wash • PSA can accumulate rapidly • PSA fills in structures • The structure itself may have been built on PSA • PSA is normally excluded from cultural resource survey

13. Recently disturbed ground • At rehab sites, ground is present that was disturbed by previous construction • Under normal circumstances, any cultural resources that might have been present, have been destroyed in those areas. • Consequently, disturbed areas are of little or no cultural resource interest. Areas disturbed by the original construction do not need to be checked for cultural resources

14. Determine where disturbance occurred during construction • Check old plans. • Ask older members of the community who might know. • Check aerial photos. • Get a soil scientist to probe the area. The soil scientist can tell you where the soil has been truncated, and by observing chaotic bedding can tell where soil has been disturbed.

15. Areas already archeologically surveyed • Some areas have already been archeologically surveyed. • Don’t under ordinary circumstances resurvey areas that have a good survey already done. Archeologists at work

16. Steep Areas • Slopes 10% or greater are unlikely to have structures or campsites • except for special resource areas such as flint outcrops, springs, and rock shelters. • Some archeological sites on summits may have eroded down slope, but this would be an area of the site that would lack integrity. Steep valley walls adjacent to the dam may not need to be archeologically surveyed

17. Tips for borrow areas • There is no cultural resources problem if you use PSA (e.g. sediment that is filling up the structure). • Nor is there a problem if you use a commercial borrow area, or borrow from previously disturbed areas. A structure filled with PSA

18. Tips for dam enlargement • Enlarging (raising and lengthening) a dam usually causes ground disturbance. • You needn’t survey areas that are already disturbed. • Areas of existing disturbance include the dam itself, the original shaping of the valley walls, existing roads (especially if it is a road structure), and existing borrow pits and spill ways.

19. Tips for access roads • Heavy equipment needs to get to the project area, which in itself can damage cultural resources. • Use existing roads (including field roads) when possible and you avoid problems. • Use areas that have a history of being driven over by tractors. Tractors exert more pressure per square inch on the ground, than heavy construction equipment. • Bulldozing a road normally requires a survey. Tractors put more pressure per square inch on the ground than construction equipment

20. Tips for altering auxiliary spillways • When dams are raised during rehab, usually the auxiliary spillway is moved upslope. • You want to know whether the new position has been previously disturbed or whether it has a slope of 10% or greater. If either or both of these conditions apply, you have little or no cultural resources problems. Auxiliary spillway

21. Tips on removing existing housing • Houses may be moved or demolished during rehab. • If the house is over 50 years of age, its significance needs to be determined. • Even a non-significant house that is moved may damage a cultural resource when it is taken to its new site. Ensure that the new site will not damage a significant resource. • Remaining basements can be grubbed out by a backhoe, without damaging undisturbed deposits. This is because of the surrounding disturbed area that was needed for the concrete forms. • Basements can be filled with PSA (e.g. ditch clean out). House threatened by potential dam breach

22. Tips for disposal of sediment • Dredging or breaching of a dam can produce large amounts of sediment. • Burying significant cultural resources with its disposal can deny access to researchers. • When possible, sediment should be disposed over disturbed ground, PSA, or very thinly “topsoiled” over cultivated fields. • If used to fill side gullies, the gullies should be surveyed. Sediment filled pool