116 C. Cls. Reporter's Statement of the Case However, we do not wish to waive our right to file a protest for the excessive cost of concrete clean-up prior to September 28, 1936, for reasons outlined in our letters of August 7th and September 25, 1936. Most of the questions raised in the latter letter were verbally_answered by you in the conference today with our Mr. T. J. Walsh and the writer. However, it will assist us in considering this matter if you will confirm by letter your answer on that portion of the letter of September 25th which deals with the formation of the pearl gray color, and the necessity for, and treatment to be used in removing same. Although this is no longer an active issue, we feel that you would clarify the situation by stating your position in the matter. 29. November 14, 1936, the construction engineer wrote plaintiffs a letter as follows: Receipt is acknowledged of your letter of November 9, 1936, with reference to your letter of September 25, 1936, protesting against our requirements in cleaning the horizontal construction joints, particularly with respect to the removal of the pearl gray deposit. This deposit first forms as calcium hydroxide, a product of the hydration of the cement, which is drawn to the surface of the concrete by capillary attraction. This material is readily soluble and is ordinarily removed by the cutting, rinsing, continuous sprinkling, and final washing, as provided in the specifications, leaving a satisfactory surface to which fresh concrete will readily bond. Equivalent results are obtained when the concrete is properly cut and rinsed and then covered with sand, providing that the sand is kept continuously moist and subsequently removed by washing and otherwise immediately preceding a fresh pour, this being the practice which is now being followed. Prior to the adoption of the moist sand method of curing, the construction joints were sprinkled only intermittently instead of continuously, as provided in the specifications, and this practice permitted objectionable quantities of the calcium hydroxide to accumulate on the surface of the concrete and, by coming in contact with the carbon dioxide in the air, to be converted into calcium carbonate, a relatively insoluble compound which is difficult to remove with a jet of air and water; but which requires sandblasting or brushing for effective removal. Reporter's Statement of the Case The sandblasting and brushing required to remove objectionable amounts of calcium carbonate, prior to the adoption of the wet sand method of curing, and to which you have objected, was necessitated by your election to cure the concrete by intermittent sprinkling rather than by continuous sprinkling, as provided in the following quotation from Paragraph 92 of the specifi cations: "The method of keeping concrete moist shall be by continuous sprinkling, spraying, or other methods approved by the contracting officer." As an alternative to the continuous sprinkling method of curing mentioned above, the wet sand method as practiced during the past month has the approval of this office. 30. September 8, 1937, plaintiffs wrote the construction engineer as follows: During last year we many times had occasion to protest your requirements in the cleaning of the horizontal contraction joints, particularly with respect to the removal of the pearl gray deposit. In your letter of November 14, 1936, you finally took the position that this matter could be corrected by a change in our methods of curing and that a wet sand method of curing would be satisfactory to you in this regard. We have attempted to use this method of curing since that time but, because of winter and other conditions, no conclusions could be reached in its regard until late this past spring. Since that time, it has become increasingly evident that the sand method of curing is not a satisfactory solution for this problem, inasmuch as your clean-up requirements are the same regardless of whether a block has been sand cured or not. Since the sand curing was an additional expense and since it did not eliminate any of the expense connected with your clean-up requirements, it became evident that this method was no longer justified and its use has, therefore, been discontinued. We will, of course, continue to use methods of curing acceptable to you and to clean up the horizontal joints to your satisfaction. However, since your clean-up requirements have always exceeded those of the specifications, we will expect to present a claim for reimbursement for such work as is not called for by them. On September 8, 1937, when the contractors discontinued the sand curing method, substantially 78 percent of the con Reporter's Statement of the Case 116 C. Cls. crete to be placed under their contract had been poured, and during the period when the sand curing method was in use, that is, from October 1936 to September 8, 1937, the contractors poured approximately 2,100,000 cubic yards of concrete, or more than 46 percent of all the concrete poured by them during the term of their contract. 31. September 15, 1937, the construction engineer wrote to plaintiffs a letter as follows: This will acknowledge receipt of your letter of September 8, in which you advise that you have discontinued the wet sand method of curing concrete placed in the dam, which has been used for some time past with our approval. The change in method of curing will be satisfactory provided the concrete be kept moist by continuous sprinkling and/or spraying as required by paragraph 92 of the specifications. 32. October 9, 1937, the construction engineer again wrote to plaintiffs a letter as follows: Receipt is acknowledged of your letter of September 8, 1937, relative to curing and clean-up requirements. Our letter of November 14, 1936, approved the wet sand method of curing the construction joints as an alternative to the continuous sprinkling method as provided in Paragraph 92 of the specifications. The results of intermittent sprinkling as generally practiced by you in lieu of continuous sprinkling as provided in the specifications, are fully set forth in our letter of November 14, 1936, and you will be expected to secure the quality of work provided for in the specifications without additional cost to the United States. 33. The removal of calcium carbonate did increase plaintiffs' costs. Plaintiffs have compiled an elaborate and complicated computation of the costs claimed by them as incurred in the removal of calcium carbonate. Plaintiffs' records do not show separately the cost of labor, material and machinery that were used in the removal of calcium carbonate. Their records show that the total clean-up costs were $1,612,768.72. The computations in the exhibit are based on allocating certain estimated percentages of the total clean-up costs to calcium carbonate. The estimated percentages were arrived at from limited observations, and 1 Reporter's Statement of the Case are too high. A fair estimate of the costs due to the removal of calcium carbonate is approximately 15% of the total clean-up costs, or $241,915.31. SECOND CAUSE OF ACTION THE REFUSAL OF THE CONTRACTING OFFICER TO PERMIT THE STRIPPING OF THE GLACIAL TILL FROM THE GRAVEL DEPOSITS 34. The Brett Gravel Pit from which the aggregates were obtained for the concrete mixes of the dam was located on a high hill 11⁄2 miles north of the dam site, on the east side of the Columbia River. The controversy in this cause of action is over the loss of profit and additional expense due to defendant's refusal to permit plaintiffs to strip and waste the so-called "glacial till" from the said pit. 35. Paragraph 34 of Specifications No. 570 provided as follows: Sand and gravel deposits.-Sand and gravel for concrete and sand for mortar, plaster, and grout shall be obtained by the contractor from the Brett gravel deposits located about 111⁄2 miles downstream from the dam site as shown on the drawings. The deposits will be acquired by the Government and will be turned over to the contractor for the purpose of furnishing the aggregates required by these specifications, as soon as they are needed by the contractor for this purpose. No charge will be made to the contractor for sand and gravel taken from these deposits for use in the work covered by these specifications. The fact that the Government is hereby designating the deposits from which the aggregates are to be obtained shall not be construed as constituting the approval of all materials taken from the deposits and the contractor will be held responsible for the specified quality of all such materials used in the work. The contractor shall carefully strip the site of the deposits or so much thereof as may be required, of top soil, vegetation, roots, brush, sod, loam, unsuitable sand and gravel, and other objectionable matter. Disposal of all materials wasted by stripping shall be subject to the approval of the contracting officer. Measurement for payment for stripping the gravel deposits will be made in excavation and will include only the stripping in locations and to the depths as directed by the contracting officer. Payment for stripping and 891357-504 Reporter's Statement of the Case 116 C. Cls. disposal of materials wasted by stripping as described in this paragraph will be made at the unit price per cubic yard bid under item 2 of the schedule. No payment will be made for any other material wasted from the gravel deposits, including excess material of any of the sizes into which the aggregates are required to be separated by the contractor and materials which have been discarded by reason of being below the minimum or above the maximum sizes specified for use. The contractor shall develop and maintain the deposits in a suitable condition for the excavation and removal of the required materials in a manner satisfactory to the contracting officer and so as to utilize at all times the greatest practicable yield of suitable materials in the portion of the deposits being worked. The screening and washing of the aggregates shall be done at the deposits or at an intermediate point, satisfactory to the contracting officer, between the deposits and the contractor's mixing plant. The location, time, sequence, and method of the washing operations shall be such as to insure that each of the various aggregates has a reasonably uniform and stable moisture content when delivered to the mixing plant. The water used for washing aggregates shall meet the requirements for water used for mixing concrete as provided in paragraph 86. The cost of all work required by this paragraph, except as provided for stripping under item 2 of the schedule, shall be included in the unit prices bid in the schedule for the items of work in which the materials obtained are used, which unit prices shall also include all expenses of the contractor in screening, washing, classifying, furnishing, hauling, storing, mixing, and other necessary operations on the aggregates. 36. The Brett gravel deposits were selected by defendant because they were the best source of concrete aggregates in sufficient quantity in the vicinity of the dam. Before the bids for the job were opened on June 18, 1934, the defendant had dug several test pits and trenches which revealed the strata and character of the deposits to be encountered. Test Pit No. 1 was completed on April 23, 1934, and was dug to a depth of 188 feet. This pit was 4 feet square and passed through glacial till. Defendant kept a log of this pit, as well as the other pits and trenches, which showed the type of material encountered. These logs prior to the date of |