COMPLIANCE INFO_PR0440063_1990-2019

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G on 6 MEMORANDUM 0 CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD - CENTRAL VALLEY REGION 3443 Routier Road, Suite A Phone: (916) 361-5600 Sacramento, CA 95827-3098 ATSS Phone: 8-495-5600 TO: WILLIAM J. MARSHALL FROM: ROBERT EVANS Senior Engineer Project Engineer Waste Discharge to Land Unit Waste Discharge to Land Unit DATE: 31 October 1991 SIGNATURE: SUBJECT: CONSTRUCTION QUALITY ASSURANCE REPORT FOR POND B, MUSCO OLIVE PRODUCTS, SAN JOAQUIN COUNTY (CASE# 2743) I have reviewed Specification and Drawings for Pond B (September 1990), Design Operations Report (February 1986), Addendum to Design Operations Report (March 1986), Preliminary Quality Assurance & Control Report (24 May 1991)and a 24 September 1991 Addendum No. 1 to the Construction Quality Assurance (CQA) report, received on 11 October 1991. The Addendum addressed many of our previous concerns. The CQA work on the Hypalon liner and the Leachate Collection and Recovery System (LCRS) was satisfactory and demonstrated that these two components were constructed to specifications and met the requirements of California Code of Regulations (CCR), Title 23, Division 3, Chapter 15 (Chapter 15). However, the Addendum did not demonstrate that the in-place permeability of the Pond B clay liner met the 1 x 10-6 cm/sec requirement. Reasons for this determination are as follows: 1. In-place permeability tests were not done on the clay liner after it was constructed. As early as 5 November 1990, we stated that the 1986 Design and Operations report was deficient due to the lack of field permeability tests. Kjeldsen-Sinnock Associates (KSA) stated that the Regional Board's staff recommendation to use the Sealed Double -Ring Infiltrometer method for determining the field permeability was not appropriate. KSA's reasons were 1) their geologist was unfamiliar with the test and they were not prepared to conduct the test; and 2) the method was not an accepted ASTM method and the repeatability of test results may not be possible. Furthermore, KSA stated that removing cores from the test pad and conducting laboratory permeability tests was an acceptable method. 2. The CQA Report relies heavily on the premise that soils which performed adequately five years ago in the construction of Pond A, should also perform adequately on Pond B. While this seems reasonable, it is also reasonable to assume that there are variations in soil characteristics within a certain soil type and variations in construction techniques from day to day. 3. Four 1986 laboratory permeability tests on Pond A, two laboratory permeability tests on the Pond B test pad and many nuclear gage tests on Pond B were used to demonstrate proper construction of the Pond B liner. No field permeability tests were conducted on either the test pads or the clay liner for Pond B. Additional information submitted in the September 1991 Addendum does not adequately demonstrate how the above information shows that the Pond B liner was constructed to meet minimum permeability requirements.