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Permanent benchmarks were set along the dam axis, on the spillway bridge, on the trashrack structure, and on the valve house floor after all construction activities had ceased.

(b) Inspection Unit. --The inspection unit was under the supervision of a chief inspector and consisted of three civil engineers, five construction inspectors, and one engineering aid. During peak construction periods, additional personnel were furnished by the laboratory and survey units. Construction work was carried out generally in stages. The tunnel outlet works were constructed during the 1949 construction season, and embankment operations were performed during 1950 and 1951 in conjunction with the completion of drilling and grouting and intermittent concrete operations in the valve house, grout cap, and spillway bridge. For this reason, inspection could be shifted to the different phases of the work as they were performed.

Six inspectors were assigned for inspection of all outlet tunnel excavation, reinforcement steel, embedded metal, and concrete lining operations; sandblasting, painting, and installation of the 48-inch wye and the 56-inch discharge pipe; earth and rock excavation for the valve house; and diamond drilling and grouting of pattern holes and voids in the outlet tunnel.

After embankment operations were commenced, one inspector was placed in charge of inspection for the completion of concrete activities in the valve house, grout cap, and spillway bridge, and installation of miscellaneous metalwork. After completion of the outlet tunnel, one inspector, at times assisted by a second inspector, was placed in charge of inspection for diamond drilling and grouting of the dam foundation. This inspector, in addition to performing these duties, also checked excavation activities for the grout cap, spillway crest wall, and spillway bridge.

On embankment operations, a crew of three inspectors and one laboratory technician was assigned to each of the two 10-hour shifts, with one inspector in charge. Inspection consisted of checking borrow pits for depth of cut and material types, final cleanup of abutments in the dam foundation, and placing of embankment materials. The laboratory technician checked the moisture inspection duties as assigned.

Daily inspection tours were made in the reservoir clearing area by regularly assigned personnel.

(c) Laboratory Unit. --The laboratory unit consisted of two civil engineers, one engineering aid, and one laborer, and was headed by a materials engineer. As work requirements were increased during the peak period of embankment operations and by concrete operations paralleling earth embankment operations, additional control inspectors were obtained from the office engineering, survey, or inspection sections.

The laboratory unit was responsible for all control testing during embankment operations. This consisted primarily of taking field density tests as required in zones 1 and 2 for compaction and moisture control and percolation-settlement tests on record control samples. Further laboratory tests, mechanical analysis and specific gravity, were performed to provide necessary data for preparation of monthly embankment reports.

Two field control inspectors were assigned to each of two 10-hour shifts worked by the contractor to perform the above mentioned testing.

39. Government Wage-Hour Forces. - Force-account work consisted chiefly of (1) providing water, sewer, and electrical systems for Platoro Government camp; (2) erecting a garage and warehouse building, laundry building, generator building, and other minor buildings; (3) installing 24 house trailer units; (4) erecting four Dallas huts; and (5) operation and maintenance of the Government camp and vehicles.

Except for the mechanic, all wage board employees were under the supervision of the camp superintendent. At maximum strength, this organization consisted of two plumbers, three carpenters, one electrician, one bulldozer operator, two truck drivers, and 18 laborers. Wage rates ranged from $1. 20 per hour for laborers to $2.24 per hour for electricians and plumbers.

Because of a lack of housing and the isolated location, it was difficult at first to recruit sufficient personnel in the skilled trades to carry on the camp construction program. However, this situation greatly improved and at the end of the 1949 working season the organization was adequately staffed. The common labor supply was always adequate.

E. Contractor's Organization

40. Prime Contractor. - Operations of the Hinman Construction Company, prime contractor (specifications No. 2594), were directed by a general superintendent, an engineer, and an office manager. The following subcontractors were employed to perform the work indicated:

Subcontractor

M. J. Bowen

(September 1951)

G. Clark

(September-October 1950)

A. E. Cowan Company (June-July 1950)

Walter Farem Company (June-July 1950)

R. B. Millay

(July-August 1949)

Rocky Mountain Welding and
Engineering Co.
(July 1950)

Work performed

Cleaning and painting all metalwork in the gate chamber, horseshoe section of the tunnel, and valve house, and the pipe handrailing on the spillway bridge. Repairing paint on the outlet pipe and glazing metal sash.

Excavating and hauling material from gravel area 2 to zones 2 and 4 of the dam embankment.

Sandblasting metal trashracks and the 56-inch and 48-inch wye section of the outlet pipe; applying CA-50 coal-tar paint to the exterior and a prime coat to the interior of the outlet pipe.

Placing cold-applied coal-tar primer and hotapplied coal-tar enamel on the interior of all sections of the outlet pipe.

Producing concrete aggregates. 3, 300 cubic yards of aggregate were produced as follows: sand, 35 percent; 3/4-inch-maximum gravel, 32.5 percent; 1-1/2-inch-maximum gravel, 32.5 percent.

Installing and welding joints of the 56- and 48-inch wye section of the outlet pipe.

41. Minor Contractors. Welch Industries, Incorporated, (specifications No. R5-13) performed their reservoir clearing work under the direction of a superintendent. They employed the following subcontractors:

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42. Employment. - Data regarding the number of employees engaged by the contractors are as follows:

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The values shown in the above tabulation include employees of subcontractors.

The wage scale paid by both contractors ranged from $1.30 an hour for heavy construction laborers to $2.50 for enamelers.

43. Safety. During the early construction period proper emphasis was not placed upon safety. As a result of efforts on the part of Reclamation personnel, however, the condition was gradually rectified as the contractor's operations became stabilized.

After some delay an adequate ventilation system was supplied for the outlet tunnel and proper precautions were adopted for handling powder and caps after delivery to the point of use from the powder house.

Haul roads were kept in good operating condition. Cuts in slide and solid rock areas, plus normal loss of material from loaded trucks, required the services of from one to three men in addition to a motor grader to keep them cleared.

The Bureau did not have a full time inspector during the entire period of construction because procurement of personnel for work at the project was consistently difficult. The contractor designated a man as safety engineer, who cooperated fully with Government personnel.

Lost-time injuries and frequency and severity rates of the prime contractor's personnel are as follows:

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Safety practices were generally good in the reservoir clearing work performed under specifications No. R5-13. Lost-time injuries and frequency and severity rates were as follows:

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F. Access Roads and Bridge

44. General. No existing roads required replacement or relocation, and no new road around the reservoir was considered necessary. Roads for access to the site were constructed by the contractor as part of this general expense 20/. The contractor's construction roads are being utilized by the Government for operation and maintenance and any necessary improvements were constructed as extra work 21/, 22/. The bridge which provides access across the spillway channel was constructed under the same specifications as was the dam.

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