Aztec Ruins Administrative History

1970-1980

It was apparent by 1970 that, despite frequent stabilization work at Aztec by dozens of the most experienced men in the business and the investment of large sums of money, the condition of the ruins was becoming worse. What initially were mere vestiges of a long-departed civilization were being further devastated. The Resources Management Plan of 1973 proposed a five-year major overhaul followed by annual preventive stabilization. [129] Additional intensive stabilization and refurbishment of earlier repair attempts were in order. These measures were to include chemical waterproofing of floors, fill, and wall bases, and chemical preservation of the masonry stone. The usual wall capping, resetting of loose stones, work on the drainage, and bracing of weakened roof beams should continue. An emergency appropriation for badly needed multiyear endeavors was solicited from the Regional Office.

Funds were made available for a three-to-four-year special preservation project. The severity of the problems so intensified as work progressed that it took six seasons and additional money to bring the Aztec Ruins to an acceptable state. Beginning in June 1973 and continuing for three or more months each summer through 1978, trained crews of five to a dozen workers, most of whom were Navajos, applied their expertise to Aztec Ruins. The first three seasons, George Chambers of the Ruins Stabilization Unit then headquartered at the Arizona Archeological Center in Tucson planned the work. Each season different trainees in ruins preservation techniques oversaw the field program. These were Peter Laudeman in 1973, Marianne Trussell in 1974, and Stephen Adams in 1975.

The team in 1973 rehabilitated 47 rooms and three kivas, principally in the West Ruin, using tinted cement and soil-cement mortars. Apparently soil-cement had returned to good standing. The workers repaired basal erosion of walls, recapped degenerate wall tops, and regrouted and replaced loose or missing stones in wall veneers. They spent a lot of time reworking Kiva N of the West Ruin and Kiva 2 in the Hubbard Mound, where hard rains during the previous winter caused considerable havoc. They replaced tile drains, whose outlets were flush with the exterior of the north wall of the West Ruin, by metal drains extending far enough beyond the wall to carry water away from its vertical face and beyond its foundation. [130]

The 1974 season of the program saw stabilization finished on 46 rooms and one kiva of the West Ruin. Again, workers carried out deep and shallow grouting, respalling, and recapping efforts with tinted cement and soil-cement mortar. They obtained stone to replace absent or decayed examples from a prehistoric quarry four miles from the monument. The same quarry was discovered to have been the source for the green stone the Anasazi used for some decorative banding. [131]

The use of tinted cement mortar, for which great promise was held when it was first introduced about 1956, began to be discontinued about this time. It developed several undesirable characteristics after being in place and exposed to the elements for several years. Its color often changed from the earth tones of recently laid mortar to an unpleasant purplish hue after it weathered. Furthermore, cement was harder than most sandstone and, when used for grouting or pointing walls, tended to outlast the construction material. A spider-web effect resulted as the harder cement in the interstices contrasted with the softer, disintegrating, coursed, sandstone blocks. The attempt at preservation was more obvious than the original substance.

The Great Kiva was reroofed in 1974 by a private constructor. The previous roof was on for 20 years and cost half as much. [132]

In 1975, Adams oversaw the rehabilitation project. It concentrated on the plaza sides of the North and East wings, by reveneering, regrouting, respalling, and recapping. Thirty-six rooms and four kivas brought the general six-year project to 83 percent completion. [133]

Although the Ruins Stabilization Unit at Tucson became an entity of the National Park Service Western Region following a 1971 realignment, for five years it continued to service Aztec Ruins, Chaco Canyon, and other areas in the Southwest Region. However, in 1976, the Southwest Region created its own stabilization team at the Navajo Lands Group in Farmington, New Mexico, an office then administering Aztec Ruins National Monument and five other National Park Service installations on or close to the Navajo Reservation. Concurrently, a research and supervisory group of preservationists, to become part of the Southwest Cultural Resources Center, was assembled in the Southwest Regional Office in Santa Fe.

During this interval, the primary repair work done at Aztec was by a commercial roofing company in Farmington. It was hired to repair seven of the roofs over the original museum rooms in the North Wing. Cement ceiling slabs laid in the 1920s were covered in 1953 by secondary roofs, which, in turn, were refurbished in 1965. The roofers stripped accumulated layers of tar, asphalt felt, and gravel down to the wooden decking and rebuilt the roofs. [134]

Stephen Adams, named ruins preservation specialist for the Navajo Lands Group, and a small crew of Navajo men from Chaco Canyon worked at rehabilitation tasks at Aztec from May to November 1977 of what comprised the fifth season of the master stabilization program. They undertook the usual relaying, recapping, and repointing repairs to 34 rooms, five clan kivas, and two axis surface rooms of the Great Kiva. Wherever possible, they knocked out loose tinted cement mortar that turned purple and replaced it with soil mortar strengthened with yet another in the roster of modern additives with which stabilizers experimented. This was Wilhold, brand name for a latex-based concrete adhesive. Workers also took down the wooden roof and sides of a late nineteenth-century root cellar at Mound F. [135]

Larry Nordby, of the Regional Office, tried to improve the drainage about Kivas N, O, V, and W, located at a featured viewpoint on the visitor trail (see Figure 12.4). Ground water soaking into walls of subterranean chambers caused stones to break down, leaving deposits of soluble salts on their surfaces. Nordby's crew implanted perforated drain pipes, bedded in gravel-filled trenches, to collect and transport water away from the ruin. These laborers relaid stones in the damaged sections of the walls and repainted them with fortified soil mortar. [136] Their work revealed that Kiva N was three nested units of different age and styles. [137]

The number of units at Aztec Ruins receiving some attention in the final year (1978) of the special long-term stabilization program reached an impressive total of 76 rooms and five kivas. Work was directed by Adams, succeeded by William Schart, ranger at the monument, and continued the process of replacing tinted cement mortar with a soil and Wilhold mixture to combat basal and veneer erosion. [138]

Important measures were initiated to replace various kinds of roofs used over a half century to protect aboriginal ceilings with modern lightweight structures of composition materials that would be self-supporting, durable, well ventilated, and easily maintained. As of 1978, protective roofs of assorted types were over West Ruin North Wing Rooms 59, 61, 112, 113, 121, 140, 143, 191, 195, 196, 197, 198, 201, and a partial one over Room 117. West Wing Rooms 132, 134, 146, 156, 178, and 179 had similar protection. In the East Ruin protective roofs were installed over Rooms 1, 2, 4, 8, 9, 11, 12, 13, 14, and 24 (partial). This left Rooms 3, 5, 6, and 7 of the East Ruin with aboriginal ceilings but no modern covering.

Adams directed the job of putting new experimental roofs on four rooms. The new superstructures consisted of urethane board, polyethylene film, and epoxy grout covered by dirt, laid upon a wooden lattice decking anchored in walls rising above the Anasazi roof. Adams left a six-inch ventilated airspace between the ancient roof and the new protective covering and secured an eyebolt in the roof for lifting it out for repairs. [139]

Another phase of the project of 1978 tackled the eternal problem of water penetration. Basal sections and floors of seven rooms in the North Wing through which the visitor trail passed were being attacked. Because the surface level outside the north walls of these rooms now is almost four feet higher than the interior floor level of the rooms, subsurface moisture and water draining off the modern roofs moved laterally through the wall bases and over the floors. Salts were deposited on the interiors of the lower walls, floors were frequently wet, and moisture trapped in the walls was subject to freezing and thawing in winter. To correct this unfavorable situation, stabilizers laid a perforated tile drainage line at the bottom of a gravel-filled trench parallel to the north exterior wall outside the seven rooms (see Figure 12.4). In digging for this pipe, they hit stubs of Chaco-style core-and-veneer walls below the ground surface, one more clue to an earlier occupation of the locale. Water was collected by the drain and routed to an irrigation ditch west of the ruin. An earlier attempt to waterproof the walls by plastering their exteriors with bitumens was not successful. [140]

Walls of the Hubbard Mound, which had been plastered with tinted cement, continued to deteriorate. Beside being unrealistic and unattractive, the cement attracted moisture and held it until it soaked into the underlying soft sandstone walls. Many stones beneath the plaster became waterlogged and fell apart on touch. Workers took the damaged plaster and its reinforcing poultry wire off most of the walls. Then, they repaired wall defects with strengthened soil mortar. They backfilled a large part of the structure to protect its fragile walls. Backfilling was predicted by Vivian 25 years earlier. After being repaired once again, some rooms and the central kiva were left open for interpretation purposes. [141]

In 1978, workmen reopened the deep drainage line along the north boundary of the monument. Installed in 1946, it functioned only sporadically, frequently becoming choked by roots of vegetation that grew along the line or filled by silt that did not flush through the line. [142]

Schart's progress report at the end of the 1978 program states, "The six-year project is now complete and definite progress has been made. However, funding and staffing at Aztec Ruins National Monument remain insufficient to carry out a maintenance program in a ruin of this size." [143] This statement may have opened the way for future additions to the permanent monument staff.

In 1979, workmen carefully removed old wood-and-tar paper roofs from seven rooms in the West Ruin and replaced them with the high-technology protective roofs Adams began installing the year before. They rebraced ceilings of four rooms not open to visitors with two-by-four-inch and four-by-four-inch timbers. They performed emergency work on parts of walls of 15 rooms that had given way during the previous winter. [144]

Over the years, so much stabilization activity took place at Aztec Ruins that periodically it became necessary to pause long enough to get it recorded and to pass along suggestions for keeping the containment situation under control. A Ruins Stabilization Guide, written by Adams in 1979, was one result. This report proposed two types of programs to be followed by local crews. One was annual maintenance. This was to include inspection of each ruin at least once a year; to maintain drains and drainage systems by removal of weeds, trash, and sand; and to make minor structural repairs as needed. The second program was a more thorough cyclic ruins maintenance, including the activities listed above plus larger structural repairs to be carried out under the guidance of a ruins stabilization specialist. [145]

The unending water problem plaguing Aztec Ruins would not go away. In April 1982, Adams was called back to the monument to attempt yet another solution. A recent study by a National Park Service hydrologist claimed that the aquifer was below the clay level in which the 1946 dragline worked. Nevertheless, Adams decided to put a French drainage system along the north side of the West Ruin to intercept the subsurface water at what he felt was the higher aquifer level (see Figure 12.4). [146] An associated earthen berm by the north monument boundary diverted surface water to a pond on private land north of the East Ruin. The French-type drain consisted of a perforated 12-inch PVC pipe laid in the bottom of a gravel-filled trench dug just five feet deep. The earlier drain was more than 20 feet deep at its maximum. Clean-outs were spaced at frequent intervals along the 900-foot drain across the rear of the West Ruin and eastward, to connect with the lower half of the old system north of the East Ruin. There, the French interceptor line was cut into the deep drain by drilling a hole into the side of a concrete manhole and connecting the PVC pipe to the manhole. This work took four months. The line has operated for the past seven years. [147]

Also in 1982, crews backfilled five West Ruin rooms not seen by visitors to ease lateral structural stress caused by differential fill in adjacent rooms. They built up the southeast side of Hubbard pond to prevent overflow. [148]