Public Scoping – Infrastructure Improvement Projects

Date: February 23, 2009
Contact: Barbara West, 505-786-7014 ext. 230

Public Scoping - Infrastructure Improvement Projects & Environmental Assessment

Chaco Culture National Historical Park is currently developing an Environmental Assessment (EA) to examine the environmental impacts associated with eleven projects that are required to improve -- through rehabilitation, repair, removal and/or replacement -- the infrastructure of the Chaco Culture National Historical Park for employee and visitor safety (NPS Strategic Management Plan, 2007) and for sustainable and efficient park operations.

The purpose of this Environmental Assessment is to examine the impacts and the cumulative effects associated with implementing these proposed projects. This EA will be prepared in accordance with the National Environmental Policy Act (NEPA) of 1969, regulations of the Council on Environmental Quality (CEQ) (40 CFR 1500-1508), and the National Park Service (NPS) (DO-12, NPS, 2001b) (Conservation Planning, Environmental Impact Analysis, and Decision-Making), Director’s Order No. 80 (Asset Management), NPS-28 (Cultural Resource Management Guideline), NPS-77 (Natural Resources Management Guideline), and NPS Management Policies (2006).

We would like to invite the public to comment on these projects. If you would like to offer your comments for consideration, please complete the comment form, and return it by March 20, 2009 to:

Barbara West,
Superintendent
Chaco Culture NHP
PO Box 220
Nageezi, NM 87037

Projects:

Project 1: Emergency - Replace Failed Septic Field at Gallo Campground.

The park’s campground leach field system has failed completely according to a U.S. Public Health Service audit (October 2006) and a subsequent engineering inspection (November 2006). The apparent cause of the failure is that the soils of the leach fields are not suitable for proper leaching. They are located in the Gallo Wash floodplain which flooded 5 times in the summer of 2006.

The park, in consultation with state regulatory authorities, determined that the leach fields at the two Gallo campground restrooms need to be abandoned and that the waste water from the campground should be treated in the park’s existing wastewater treatment system. To accomplish this, the planned project will construct a small pressurized system to move sewage from both campground restrooms to the housing area lift station wet well located 1.2 miles from the campground. The sewage will then be pumped by the park’s primary lift station to the mesa top sewage lagoons. The lift station has more than adequate capacity to handle the addition of the campground sewage. Design and specifications will be developed by Santa Fe engineering staff, and all new construction will be contracted. To minimize the possibility of affecting cultural resources, the route for the utility corridor will follow the campground road to the park’s entrance road. The trench will follow the outside alignment of the entrance road in already disturbed soils. Finally, it will cross the road to access the existing well. Eventually the park will remove and decommission the abandoned septic tanks and leach fields, although those actions are not anticipated as part of this project. The proposed project will be sustainable and much easier to maintain than the existing system.  

Project 2: Repair and Rehabilitate Gallo Campground RV Dump Station. 

This project will replace two existing 500-gallon septic tanks with one 2,000-gallon septic tank for the campground RV Dump station. The project will excavate, remove and dispose of the current tanks and install the new, larger tank in the same location. In conjunction with Project 1 above, the tanks will be plumbed into the sewage handling system for the Gallo Campground so that the dump station sewage will be pumped to the lift station. The area disturbed by the trench will follow the campground access road to minimize potential effects to cultural and natural resources.

Project 3: Replace Water Line. 

This project will replace 6,000 linear feet of 30 to 50 year old PVC underground water lines to provide reliable non-potable water delivery to the visiting public for the campground. PVC pipe will replace the existing lines. The project will include trenching to replace the lines in trench away from known archeological sites under the existing park road. Approximately 200 feet of line will be relocated to eliminate a 90-degree turn in the line. This will prevent water hammer and future breakage. This project will be done in conjunction with project 1 so that the same trenching equipment and archeological monitoring can be used for both projects.

Project 4: Replace 75,000 Gallon Water Tank.

This project will remove and replace, in the same location, the existing deteriorated steel 75,000 gallon above ground non-potable water storage tank located on the mesa top adjacent to the park’s developed area. The tank stores water for fire emergency response through hydrants, for all flushable toilets/comfort stations throughout the park, and provides water pressure for the distribution system. The tank is located on the mesa top adjacent to the well head.

Project 5: Emergency – Replace Propane Lines.

This emergency project will replace 3,600 linear feet of propane gas line. The existing galvanized steel pipe that delivers propane fails to meet state or federal codes. Leaks have been detected by gas monitors in confined spaces during water line repairs. Staff noticed, during those repairs, that the soils surrounding the 3/4-inch propane pipe are a deep black color indicating a prolonged propane exposure. The original 3/4-inch galvanized steel has corroded in Chaco’s alkaline soils and some seams leak despite the welded threaded joints. The existing galvanized steel lines will be replaced to code with polyethylene pipe and will be marked in compliance with ASTM D2513. The gas lines serve more than half the park’s assets including the visitor center and museum, two campground restrooms, the park’s water supply and well house, facilities shop, and sixteen park residences. The project will also replace the outdated (25+ years old and in some instances, malfunctioning) gas meters. New meters will be installed to detect potential leaks.

Project 6: Correct Critical Phone System Deficiencies.

This project will replace 3,400 feet of buried telephone cables. The existing telephone line system (over 15 years old) is not reliable and the system lacks the capacity to serve several buildings that by NPS policy should have phone connections -- the museum storage building which houses parts of the park’s collections and the hazmat building. There are currently no additional working telephone lines available to support those facilities. Approximately 30 months ago, a 25 pair telephone line serving the maintenance office and the residential area failed and the telephone company installed a temporary 6 pair telephone line on an emergency basis. The temporary line is not buried, lies wholly above ground and is subject to deterioration from weather and the harsh desert environment. As a consequence, callers to the park often hear an echo when they call the park. The emergency telephone lines will be replaced in-kind. Old telephone cables and junction boxes will be removed. Under paved sections of the road, the new cables will be installed in PVC pipe conduit and will be properly grounded. The conduit for the phone lines will be located in the same trench as the new propane lines, Project 5, when possible. This will obviate the need for two separate trenches in some areas and will further rationalize the park’s utility systems. All the telephone lines will be buried to reduce fire hazards, increase visitor and employee safety, and enhance visitor experience. Once the system is completed to industry standards, Frontier Communications will accept responsibility for maintaining the lines which should provide long-term savings to the park.

Project 7: Replace Potable Water System Valves and Meters.

The park will replace 18 potable water system valves and 18 water meters to the maintenance complex and housing area buildings including the shop, maintenance office, well house, apartments, houses, trailers, and VIP campground. The water valves have deteriorated such that a cyclic repair project will not significantly extend their service life. Further, the valves are underground, often malfunction and have broken valve stems.

Project 8: Cyclic Repair of Flood Control Features for Gallo Wash Campground.

This project will repair and maintain the flood and erosion control features-- specifically the masonry drop structures, dikes and gabions -- that provide flood control to the park’s only campground and primary entrance road. The features were constructed in the 1950’s and have not been routinely maintained. The long-term viability of two major assets -- park road and the campground -- depends on the proper functioning of these features.

Project 9: Cyclic Maintenance: Water Tank Road.

This project will clean out culverts, add and compact road base, and surface grade sections of the park’s Water Tank Road RT0402.

Project 10: Rehabilitate Visitor Center Area Drainage.

This project will correct the effects of some serious erosion and soil piping between the Visitor Center and main park loop road. An A&E contract will evaluate, engineer, and remediate the failed culvert drainage within the VC area. At the end of a 2ft diameter culvert, several rock gabions and filter fabric sections have failed and are undermined with soil piping (a type of fine sediment erosion). Water runoff spills from the VC area culvert and vertically drops 25 ft – further undermining the failed rock gabions and filter fabric sections. The drainage is beginning to undercut the main park loop road and VC area intersection. A construction firm will install a new 100ft section on the existing culvert, demolish and remove the failed erosion control features, and fill/compact at 4 inch lifts to meet the culvert drainage grade. 

Project 11: Cyclic Maintenance of Maintenance Area Sandstone Masonry Retaining Walls.

This project will provide cyclic maintenance on a 7 year cycle for 1200 LF of maintenance area retaining walls. Mortar may be replaced as well. The sandstone block walls have a mean height of 4ft and the project will repoint (or replace, as necessary) the mortar between the sandstone blocks. The tops of the walls, or caps, will be re-mortared by park staff.