06-096DEPARTMENT OF ENVIRONMENTAL PROTECTION
alternative closure procedure of 38 MRSA. Section 1310-E(3) must continue as previously approved for the facility, unless an alternative program is established in the closing plan and post-closure care approval for the landfill. If the landfill does not have an approved monitoring program, one must be established during 1998 in accordance with the applicable requirements. The sampling frequency and parameters for closed landfills are expected to decrease throughout the post-closure period.
(i)If the results of detection monitoring indicate a possible deterioration in water quality at one or more ground water monitoring wells or surface water monitoring points, the owner/operator of the solid waste facility shall initiate an evaluation of the causes of the deterioration in water quality within 30 days of its receipt of the laboratory results. A report of the evaluation, prepared and sealed by a qualified professional, must be submitted to the Department for review and approval within 90 days of the date the evaluation is initiated. The report may be a part of the regular monitoring report or a separate document. The evaluation must include the following:
(i)a statistical analysis of the data from the monitoring program, performed in accordance with Section 3 .
(ii)an evaluation of sources other than the solid waste facility which may have caused or contributed to the possible deterioration in water quality, such as natural variation in water quality or another development.
(iii)an evaluation of possible errors, such as errors in sampling, analysis, or mathematical problems with the monitoring data. If resampling of monitoring points is performed, the samples must be independent of the previous sample; however, the sample must be collected within the same season as the original sample.
NOTE: Staff consider "possible deterioration" to mean a change in data values that appears significant after considering normal variations in the historical database and any acute events that might have triggered short-term water quality changes.
(j)Assessment monitoring must be initiated within 90 days of the date the report required by Section 2.C(2)(i), above, is submitted, unless the Department concurs that a source other than the solid waste facility is the likely source of the deterioration in water quality. Assessment monitoring must be conducted in accordance with a plan approved by the Department.
(3)Assessment monitoring. The purpose of assessment monitoring is to determine the nature and extent of a release of contaminants to ground or surface water.
(a)Proposed changes to the facility’s water quality monitoring plan, prepared in accordance with the applicable rules, must be submitted at least 15 days prior to the first scheduled assessment monitoring event.
(b)Assessment monitoring frequency must include three sampling events per year collected during spring (March/April), summer (July/August) and fall (October/November) at each sample point where it is documented by a statistically significant change in concentration of a parameter that deterioration of water quality has occurred, and at its upgradient or upstream counterpart(s).
(c)Samples taken during the first two rounds of assessment monitoring must be analyzed for the Column 3 parameters. After the submission of the results from the first two rounds of assessment
Chapter 405: Water Quality Monitoring, Leachate Monitoring, and Waste Characterization
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