La. Admin. Code tit. 33 § VII-805

Current through Register Vol. 50, No. 6, June 20, 2024

Section VII-805 - Facility Groundwater Monitoring

A. Groundwater Monitoring System. The following facility groundwater monitoring standards are applicable to all Type I and Type II facilities.

1. At each facility, a groundwater-monitoring system shall be installed that consists of a sufficient number of wells, installed at appropriate locations and depths, in accordance with Paragraph A.2 of this Section, to yield groundwater samples from the uppermost aquifer, and from the uppermost water-bearing permeable zone(s), to yield sufficient quantities of water for sampling that:

a. represent the quality of the background groundwater that has not been affected by leakage from a unit; and

b. represent the quality of groundwater passing the relevant point of compliance. For the purposes of these regulations, the relevant point of compliance is the vertical surface that is located no more than 150 meters downgradient from the unit being monitored and extends down into the uppermost aquifer underlying the facility and any other permeable zones being monitored. The distance may be reduced by the administrative authority. The relevant point of compliance shall be on property owned or controlled by the permit holder and shall be selected based on at least the following factors:

i. hydrological characteristics of the facility and the surrounding land;

ii. volume and physical and chemical characteristics of the leachate;

iii. quantity, quality, and direction of flow of groundwater;

iv. proximity and withdrawal rate of the groundwater users;

v. availability of alternative drinking water supplies;

vi. existing quality of the groundwater, including other sources of contamination and their cumulative impacts on the groundwater, and whether the groundwater is currently used or reasonably expected to be used for drinking water; and

vii. public health, safety, and welfare effects.

2. Location of Wells

a. Enough monitoring wells shall be located hydraulically upgradient of the facility to yield samples that represent background groundwater quality as required in Paragraph A.1 of this Section.

b. A minimum of one upgradient well per zone monitored is required.

c. Monitoring wells other than upgradient of the facility may be sampled for background groundwater quality if:

i. hydrologic conditions do not allow the permit holder to determine which wells are hydraulically upgradient; or

ii. sampling at other wells will provide an indication of background groundwater quality that is more representative than sampling of upgradient wells.

d. Enough monitoring wells shall be located hydraulically downgradient from the facility to yield samples that are representative of the groundwater passing the relevant point of compliance. Downgradient monitoring well locations and screen intervals shall target the most likely contaminant pathways. At least two downgradient wells per zone monitored shall be provided. The downgradient wells shall be screened in the same zone as the upgradient wells. Spacing between downgradient wells shall not exceed 800 feet.

e. The number, spacing, and depths of monitoring wells shall be determined based upon site-specific technical information that shall include thorough characterization of:

i. aquifer thickness, groundwater flow rate, and groundwater flow direction including seasonal and temporal fluctuations in groundwater flow; and

ii. saturated and unsaturated geologic units and fill materials overlying the uppermost aquifer, materials comprising the uppermost aquifer, and materials comprising the confining unit defining the lower boundary of the uppermost aquifer, including, but not limited to, thickness, stratigraphy, lithology, hydraulic conductivities, porosities, and effective porosities.

f. The administrative authority will consider for approval multi-unit groundwater monitoring systems, provided these systems meet the requirements of Paragraph A.1 of this Section and will be as protective of human health and the environment as groundwater monitoring systems for individual units.

g. The administrative authority may modify the requirements of this Subsection for site-specific considerations in approving groundwater monitoring systems for ditches.

3. Well Construction

a. Well construction shall be in accordance with the Water Well Rules, Regulations, and Standards, as adopted by the Louisiana Department of Transportation and Development, Water Resources Section, in LAC 56, as well as the guidelines established in the latest version of the LDEQ's and LDOTD's Construction of Geotechnical Boreholes and Groundwater Monitoring Systems Handbook.

b. Construction of monitoring wells for facilities regulated by the department shall require approval of the administrative authority prior to construction.

c. In addition to the construction standards set forth in LDOTD's Water Well Rules, Regulations, and Standards, the following is required for monitoring wells.

i. All wells shall have protective casing with locking covers and a secure locking device in place.

ii. All wells shall have guard posts firmly anchored outside the well slab, but not in contact with the slab.

iii. The maximum allowable screen length shall not exceed 10 feet.

iv. A sign or plate shall be permanently affixed to the protective well casing and shall prominently display:

(a) the well identification number;

(b) identification of the well as upgradient or downgradient;

(c) the elevation of the top of the well casing in relation to NGVD;

(d) screen depth in relation to NGVD; and

(e) the date of well installation and any subsequent repairs.

4. Post Construction. Within 90 days after construction of the wells, the permit holder or applicant shall submit to the Office of Environmental Services well completion details to verify that the wells were constructed according to the approved specifications and to document construction procedures. A permit modification fee will not be required. Well-completion details shall include, but are not limited to:

a. daily field notes documenting construction procedures and any unusual occurrences, such as grout loss, etc.;

b. a boring log for each well including surface elevation with respect to NGVD or comparable reference points; and

c. well-completion diagrams for each well showing all pertinent features, such as the elevation of the reference point for measuring groundwater levels, screen interval, and ground surface. If features change from the approved plans, then a permit-modification request shall be submitted in accordance with LAC 33:VII.517.

5. Plugging and Abandonment of Monitoring Wells and Geotechnical Borings

a. The Water Well Rules, Regulations, and Standards, as adopted by the Louisiana Department of Transportation and Development, Water Resources Section, in LAC 56, as well as the guidelines established in the latest version of the LDEQ's and LDOTD's Construction of Geotechnical Boreholes and Groundwater Monitoring Systems Handbook, shall apply to all plugging and abandonment of wells and holes including, but not limited to, observation wells, monitoring wells, piezometer wells, leak-detection wells, assessment wells, recovery wells, abandoned pilot holes, test holes, and geotechnical boreholes.

b. In addition to the standards in LDOTD's Water Well Rules, Regulations, and Standards and in the latest version of the LDEQ's and LDOTD's Construction of Geotechnical Boreholes and Groundwater Monitoring Systems Handbook, the following standards shall apply to plugging and abandonment.

i. For any well, the primary method of plugging and abandonment shall be removal of the well's casing and other components of the well, including, but not limited to, the screen, grout, bentonite seal, filter pack, concrete slab, protective casing, guard posts, and native soil in immediate contact with the grout, and subsequent installation of cement-bentonite grout, from the bottom of the resulting borehole to the ground surface using the tremie method.

ii. In areas where all or a part of the well's casing and other components of the well cannot be plugged and abandoned in accordance with the procedure stated in Clause A.5.b.i of this Section, the well shall be plugged and abandoned by installation of cement-bentonite grout inside the well's casing, from the bottom of the well to the ground surface, provided that the annular seal is demonstrated to be adequately sealed and the following items are submitted:

(a). supporting documentation, prior to plugging the well, that demonstrates that removal of all or part of the well's casing and other components of the well in accordance with the procedure stated in Paragraph A.5 of this Section will be detrimental to the environment; and/or

(b). certification and supporting documentation by a qualified professional well constructor that shows that removal of the well's casing was attempted and that continued attempts to remove all or a part of the well's casing and other components of the well, as stated in Paragraph A.5 of this Section, would have been detrimental to the environment.

iii. After plugging and abandoning a well, all surface features of the well, including, but not limited to, the concrete slab, guard posts, and protective casing, shall be dismantled and disposed of in an environmentally sound manner, and the surface shall be restored to its original condition.

iv. The permit holder shall notify the Office of Environmental Services of the plugging and abandonment of monitoring wells or geotechnical borings and keep records of such abandonments.

6. Monitoring wells, piezometers, and other measurement, sampling, and analytical devices shall be operated and maintained so that they perform to design specifications throughout the life of the monitoring program.

B. Groundwater Sampling and Analysis Requirements

1. A groundwater-monitoring program shall be implemented, at each facility, that includes consistent sampling and analysis procedures that ensure monitoring results are representative of groundwater quality at the background and downgradient well locations.

2. A groundwater sampling and analysis plan shall be prepared that meets the requirements of this Subsection, as well as the requirements of LAC 33:VII.3005.Appendix C, and that includes procedures and techniques for:

a. sample collection that ensures that collected samples are representative of the zones being monitored and that prevents cross-contamination of or tampering with samples;

b. sample preservation and shipment that ensure the integrity and reliability of the sample collected for analysis;

c. chain of custody control;

d. quality-assurance/quality-control, including detection limits, precision and accuracy of analyses, rinsate samples, field blanks, trip blanks, field duplicates, and matrix spikes/matrix spike duplicates; and

e. statistical evaluation of the groundwater monitoring data for each parameter or constituent sampled at each monitoring well.

3. The sampling and analysis plan shall provide the sampling frequency and include:

a. the selection of parameters or constituents to be sampled and analyzed during detection monitoring, and justification for the parameters or constituents, where applicable;

b. identification of the analytical procedures to be followed (reference source of analytical method); and

c. the practical quantitation limit (PQL) for each parameter or constituent.

4. The PQL for each groundwater monitoring parameter or constituent shall be:

a. the lowest concentration level that can be reliably achieved within specified limits of precision and accuracy during routine laboratory operating conditions that are available to the facility; and

b. equal to or lower than the groundwater protection standard for that parameter or constituent as set in accordance with LAC 33:I.Chapter 13, when applicable.

5. Background groundwater quality shall be established for the facility in a hydraulically upgradient well, or other well as provided in Subparagraph A.2.c of this Section, for each groundwater parameter or constituent.

6. Statistical Methods

a. The number of samples collected to establish groundwater quality data shall be consistent with the appropriate statistical procedures used. A decision tree diagram is included in LAC 33:VII.3005.Appendix C, as a reference in the selection of an appropriate statistical procedure.

b. The statistical methods used in evaluating groundwater data shall be specified in the sampling and analysis plan for each parameter or constituent to be monitored. The statistical test chosen shall be conducted separately for each parameter or constituent in each well. One of the following statistical methods shall be used:

i. a parametric analysis of variance (ANOVA) followed by multiple comparisons procedures to identify statistically significant evidence of contamination. The method shall include estimation and testing of the contrasts between each compliance well's mean and the background mean levels for each parameter or constituent;

ii. an analysis of variance (ANOVA) based on ranks followed by multiple comparisons procedures to identify statistically significant evidence of contamination. The method shall include estimation and testing of the contrasts between each compliance well's median and the background median levels for each parameter or constituent;

iii. a tolerance or prediction interval procedure in which an interval for each parameter or constituent is established from the distribution of the background data, and the level of each parameter or constituent in each compliance well is compared to the upper tolerance or prediction limit;

iv. a control chart approach that gives control limits for each parameter or constituent; or

v. another statistical test method that meets the performance standards of Subparagraph B.6.c of this Section. The permit holder shall place a justification for this alternative in the operating record and notify the administrative authority of the use of this alternative test. The justification shall demonstrate that the alternative method meets the performance standards of Subparagraph B.6.c of this Section.

c. Any statistical method chosen under Subparagraph B.6.b of this Section shall comply with the following performance standards, as appropriate.

i. The statistical method used to evaluate groundwater monitoring data shall be appropriate for the distribution of the parameters or constituents. If the distribution of the chemical parameters or constituents or hazardous parameters or constituents is shown by the permit holder to be inappropriate for a normal theory test, then the data should be transformed or a distribution-free theory test should be used. If the distributions for the parameters or constituents differ, more than one statistical method may be needed.

ii. If an individual well comparison procedure is used to compare an individual compliance well parameter or constituent concentration with background parameters or constituent concentrations or a groundwater protection standard, the test shall be done at a Type I error level no less than 0.01 for each testing period. If a multiple comparisons procedure is used, the Type I experiment-wide error rate for each testing period shall be no less than 0.05; however, the Type I error of no less than 0.01 for individual well comparisons shall be maintained. This performance standard does not apply to tolerance intervals, prediction intervals, or control charts.

iii. If a control chart approach is used to evaluate groundwater monitoring data, the specific type of control chart and its associated parameter or constituent values shall be protective of human health and the environment. The parameters or constituents shall be determined after considering the number of samples in the background data base, the data distribution, and the range of the concentration values for each parameter or constituent of concern.

iv. If a tolerance interval or a predictional interval is used to evaluate groundwater monitoring data, the levels of confidence and, for tolerance intervals, the percentage of the population that the interval shall contain, shall be protective of human health and the environment. These parameters or constituents shall be determined after considering the number of samples in the background data base, the data distribution, and the range of the concentration values for each parameter or constituent of concern.

v. The statistical method shall account for data below the limit of detection with one or more statistical procedures that are protective of human health and the environment. Any practical quantitation limit (PQL) that is used in the statistical method shall be the lowest concentration level that can be reliably achieved within specified limits of precision and accuracy during routine laboratory operating conditions that are available to the facility.

vi. If necessary, the statistical method shall include procedures to control or correct for seasonal and spatial variability as well as temporal correlation in the data.

d. The permit holder shall determine whether or not there is a statistically significant increase over background values for each parameter or constituent required in the particular groundwater monitoring program that applies to the facility, as determined in Subsections C and D of this Section.

i. In determining whether a statistically significant increase has occurred, the permit holder shall compare the groundwater quality of each parameter or constituent at each monitoring well designated in accordance with Subparagraph A.1.b of this Section to the background value of that parameter or constituent, according to the statistical procedures and performance standards specified under Subparagraphs B.6.b and c of this Section.

ii. Within 90 days after the date of sampling, the permit holder shall determine whether there has been a statistically significant increase over background at each monitoring well.

C. Detection Monitoring Program

1. All Type I and II facilities shall conduct a detection monitoring program as described in this Subsection.

2. Initial Sampling

a. For a new facility, monitoring wells shall be sampled and the groundwater monitoring data for a sampling event shall be submitted to the Office of Environmental Services before waste is accepted.

b. For an existing facility with no wells in place at the time of the application submittal or at the time at which the facility becomes subject to these regulations, the groundwater monitoring data shall be submitted to the Office of Environmental Services within 90 days after installation of the monitoring wells.

c. A minimum of four independent samples from each well (upgradient and downgradient) shall be collected and analyzed during the initial sampling event for a facility. The initial sampling event shall consist of quarterly sampling over a 1-year period. Thereafter, at least one sample shall be collected and analyzed at each well for each sampling event.

3. After the initial 1-year sampling event, sampling and analysis of all wells shall be conducted every six months.

4. The groundwater monitoring program shall be conducted for the life of the facility and for the duration of the post-closure care period of the facility, which is specified in LAC 33:VII.721.E or 723.E. Groundwater monitoring may be extended beyond the period specified if deemed necessary by the administrative authority.

5. The permit holder or applicant shall submit three bound copies (8 1/2 by 11 inches) of a report of all groundwater sampling results to the Office of Environmental Services no later than 90 days after each sampling event.

a. The reports shall be submitted on forms provided by the administrative authority and shall include, at a minimum:

i. documentation of the chain of custody of all sampling and analyses;

ii. scaled potentiometric surface maps showing monitoring well and piezometer locations and groundwater elevations with respect to NGVD for each stratum monitored;

iii. plots by well showing concentration of parameters or constituents versus time. If the facility is conducting assessment or corrective action monitoring, then in addition to the plots by well of concentration versus time, an isopleth map shall be submitted for each zone monitored; and

iv. a statement of whether a statistically significant difference in concentration over background concentrations is detected.

b. The administrative authority may waive or require information to be included in each groundwater sampling report.

6. If a statistically significant increase over background concentrations is determined for one or more parameters or constituents required to be monitored, the permit holder shall:

a. submit to the Office of Environmental Services:

i. within 14 days after the determination is made, a report that identifies which parameters or constituents were determined to have shown statistically significant changes over background levels; and

ii. written notification at least 14 days prior to conducting any verification resampling event; and

b. within 90 days after the determination is made:

i. initiate an assessment monitoring program for the facility meeting the requirements of Subsection D of this Section; or

ii. submit a report to the Office of Environmental Services demonstrating that a source other than the facility being sampled caused the contamination or that the statistically significant increase resulted from an error in sampling, analysis, statistical evaluation, or natural variation in groundwater quality. If the administrative authority approves this demonstration, in writing, the permit holder may continue the detection monitoring program. If the administrative authority does not approve the demonstration, in writing, the permit holder shall establish an assessment monitoring program meeting the requirements of Subsection D of this Section within 90 days after the determination in this Paragraph is made.

7. Detection Monitoring Parameters or Constituents

a. During detection monitoring, Type I landfills and Type I surface impoundments (except Type I landfills that are also Type II landfills and Type I surface impoundments that are associated with such Type I landfills) shall monitor for at least 10 chemical parameters or constituents, both inorganic and organic, that are indicator parameters or constituents or reaction products of the waste and that provide a reliable indication of the presence of contaminants in the groundwater. The administrative authority may reduce the number of parameters, if appropriate, based on sitespecific and waste-specific consideration. Selection of these parameters or constituents is subject to the approval of the administrative authority and shall be based on the following factors:

i. types, quantities, and concentrations of constituents in the wastes disposed of at the facility;

ii. mobility, stability, and persistence of waste constituents or their reaction products in the unsaturated zone beneath the facility;

iii. detectability of indicator parameters, waste constituents, or their reaction products in the groundwater; and

iv. concentrations or values and coefficients of variation of the proposed monitoring parameters or constituents in the background groundwater at the facility.

b. During detection monitoring, Type II landfills, including Type II surface impoundments associated with Type II landfills, shall be monitored for all the parameters or constituents listed in LAC 33:VII.3005.Appendix C, Table 1.

c. During detection monitoring, Type I landfarms, including runoff and containment areas (ROCAs) or surface impoundments associated with Type I landfarms, shall be monitored for the same parameters or constituents as provided for Type II landfarms in Subparagraph C.7.d of this Section and also for at least six parameters or constituents, both organic and inorganic, that are intrinsic to the wastes being disposed at the facility. The intrinsic parameters or constituents shall be selected on the basis of the factors in Clauses C.7.a.i-iv of this Section and shall be subject to the approval of the administrative authority.

d. During detection monitoring, Type II landfarms, including runoff and containment areas (ROCAs) or surface impoundments associated with such landfarms, shall be monitored for 5-day biochemical oxygen demand (BOD5), fecal coliform, total dissolved solids (TDS), nitrate, total Kjeldahl nitrogen, and polychlorinated biphenyls (PCBs), if applicable.

e. Type II surface impoundments shall be monitored for the same parameters or constituents as provided for Type II landfarms in Subparagraph C.7.d of this Section.

f. The administrative authority may waive or require additional parameters or constituents, based on sitespecific or waste-specific information.

D. Assessment Monitoring Program for Type I and Type II Facilities

1. An assessment monitoring program as described in this Subsection is required to be conducted at Type I and Type II facilities whenever a statistically significant increase over background concentrations is detected for one or more of the parameters or constituents sampled and analyzed during the detection monitoring program.

2. The assessment monitoring parameters for:

a. Type II landfills and associated Type II impoundments shall be the parameters listed in Table 2 of LAC 33:VII.3005.Appendix C; and

b. Type I and Type II facilities, other than Type II landfills and associated Type II impoundments, shall be the detection monitoring parameters or constituents listed in Table 1 of LAC 33:VII.3005.Appendix C, although the administrative authority may add additional parameters or constituents on a site-specific and waste-specific basis.

3. Within 90 days of triggering an assessment monitoring program, and annually thereafter, the permit holder shall sample and analyze the groundwater for the assessment monitoring parameters or constituents. A minimum of one sample from each downgradient well shall be collected and analyzed during each sampling event. For any parameter or constituent detected in the downgradient wells as a result of sampling for the assessment monitoring parameters or constituents, a minimum of four independent samples from each well (background and downgradient) shall be collected and analyzed to establish background for the parameters or constituents.

a. The administrative authority may specify an appropriate subset of the wells to be sampled and analyzed for assessment monitoring parameters or constituents during assessment monitoring.

b. The administrative authority may delete any of the assessment monitoring parameters or constituents for a facility if it can be shown that the omitted parameters or constituents are not reasonably expected to be in or derived from the waste contained in the unit.

4. No later than 90 days after the completion of the initial or subsequent sampling events for all assessment monitoring parameters or constituents required in Paragraph D.3 of this Section, the permit holder shall submit a report to the Office of Environmental Services, identifying the assessment monitoring parameters or constituents that have been detected. No later than 180 days after completion of the initial or subsequent sampling events for all assessment monitoring parameters or constituents required in Paragraph D.3 of this Section, the permit holder shall:

a. resample all wells and analyze for all detection monitoring parameters or constituents and for those assessment monitoring parameters or constituents that are detected in response to Paragraph D.3 of this Section. At least one sample shall be collected from each well (background and downgradient) during these sampling events. This sampling shall be repeated semiannually thereafter;

b. establish background groundwater concentrations for any parameter or constituent detected in accordance with Paragraph D.3 or 4 of this Section; and

c. establish groundwater protection standards for all parameters or constituents detected in accordance with Paragraph D.3 or 4 of this Section. The groundwater protection standards shall be established in accordance with Paragraph D.8 of this Section.

5. If the concentrations of all assessment monitoring parameters or constituents are shown to be at or below background values, using the statistical procedures in Paragraph B.6 of this Section or other EPA-approved methods for comparison to a fixed limit (such as an MCL), for two consecutive sampling events, the permit holder shall notify the Office of Environmental Services and, upon written approval of the administrative authority, may return to detection monitoring.

6. If the concentrations of any assessment monitoring parameters or constituents are above background values, but all concentrations are below the groundwater protection standard established under Paragraph D.8 of this Section, using the statistical procedures in Paragraph B.6 of this Section or other EPA-approved methods for comparison to a fixed limit (such as an MCL), the permit holder will be placed in assessment monitoring for the life of the facility or until the assessment monitoring parameters are below the established background values. As part of the corrective action development, the permit holder shall submit a work plan for approval to the Office of Environmental Services.

a. This work plan shall include:

i. proposal of additional groundwater wells outside the area of contamination in order to demonstrate that the facility has control of the plume and/or source of contamination;

ii. proposal of semiannual groundwater monitoring reports demonstrating that the concentrations of the constituents of concern is not increasing;

iii. a scaled figure depicting the location of the area of investigation, existing and proposed groundwater monitoring wells, and property boundaries;

iv. scaled potentiometric maps depicting water elevations of all existing and proposed monitoring wells. These maps shall be submitted as part of the semiannual groundwater monitoring reports; and

v. an isopleth map for each well of all parameters or constituents, or plots by well concentration of parameters or constituents verses time.

b. The Office of Environmental Services may request additional information based on the data submitted in the work plan.

7. If one or more assessment monitoring parameters or constituents are detected at statistically significant levels above the groundwater protection standard established in Paragraph D.8 of this Section, in any sampling event, using the statistical procedures in Paragraph B.6 of this Section or other EPA-approved methods for comparison to a fixed limit (such as an MCL), the permit holder shall, within 14 days of the determination, notify all appropriate local government officials and submit a report to the Office of Environmental Services identifying the assessment monitoring parameters or constituents that have exceeded the groundwater protection standard. The permit holder shall comply with one of the following requirements.

a. The permit holder shall:

i. within 90 days after the determination is made, submit four bound copies (8 1/2 x 11 inches) of an assessment plan to the Office of Environmental Services, as well as any necessary permit modification, that provides for:

(a). characterization of the nature and extent of the release by installing and sampling additional monitoring wells as necessary;

(b). installation of at least one additional monitoring well at the facility boundary in the direction of the contaminant migration and sampling of this well in accordance with Subparagraph D.4.b of this Section; and

(c). a schedule for implementing the plan;

ii. notify all persons who own the land or reside on the land that directly overlies any part of the plume of contamination if contaminants have migrated off site as indicated by the sampling of the wells in accordance with Clause D.7.a.i of this Section;

iii. upon consultation with and approval of the administrative authority, implement any interim measures necessary to ensure the protection of human health and the environment. Interim measures shall, to the greatest extent practicable, be in accordance with LAC 33:I.Chapter 13 and be consistent with the objectives of and contribute to the performance of any remedy that may be required in accordance with Subsection F of this Section. The following factors shall be considered by a permit holder in determining whether interim measures are necessary:

(a). the time required to develop and implement a final remedy;

(b). actual or potential exposure of nearby populations or environmental receptors to hazardous parameters or constituents;

(c). actual or potential contamination of drinking water supplies or sensitive ecosystems;

(d). further degradation of the groundwater that may occur if remedial action is not initiated expeditiously;

(e). weather conditions that may cause hazardous parameters or constituents to migrate or be released;

(f). risk of fire or explosion, or potential for exposure to hazardous parameters or constituents as a result of an accident or failure of a container or handling system; and

(g). other situations that may pose threats to human health and the environment;

iv. initiate an assessment of corrective measures as required by Subsection E of this Section.

b. If the facility being sampled did not cause the contamination, the permit holder may submit a report to the Office of Environmental Services demonstrating that a source other than the facility being sampled caused the contamination, or the statistically significant increase resulted from error in sampling, analysis, statistical evaluation, or natural variation in groundwater quality. If the administrative authority approves this demonstration in writing, the permit holder shall continue assessment monitoring at the facility in accordance with this Subsection or may return to detection monitoring if the assessment monitoring parameters or constituents are below background as specified in Paragraph D.5 of this Section. Until such a written approval is given, the permit holder shall comply with Subparagraph D.7.a of this Section, including initiating an assessment of corrective action measures.

8. The permit holder shall establish a groundwater protection standard for each assessment monitoring parameter or constituent detected in the groundwater. The groundwater protection standard shall be in accordance with LAC 33:I.Chapter 13.

E. Assessment of Corrective Measures at Type I and Type II Facilities

1. Within 90 days of finding that any of the assessment monitoring parameters or constituents listed in Table 2 of LAC 33:VII.3005.Appendix C have been detected at a statistically significant level exceeding the groundwater protection standards defined in Paragraph D.8 of this Section, the permit holder shall initiate an assessment of corrective measures.

2. The permit holder shall continue to monitor in accordance with the assessment monitoring program throughout the period of corrective action, as specified in Subsection D of this Section.

3. The assessment shall include an analysis of the effectiveness of potential corrective measures in meeting all of the requirements and objectives of the remedy as described in Subsection F of this Section, addressing at least the following:

a. performance, reliability, ease of implementation, and potential impacts of appropriate potential remedies, including safety impacts, cross-media impacts, and control of exposure to any residual contamination;

b. the time required to begin and complete the remedy;

c. the costs of remedy implementation; and

d. institutional requirements such as state or local permit requirements or other environmental or public health requirements that may substantially affect implementation of the remedy.

4. For Type II landfills and associated surface impoundments, the results of the corrective measures assessment shall be discussed by the permit holder, in a public meeting prior to the selection of remedy, with interested and affected parties.

F. Selection of Remedy and Corrective Action Plan at Type II Landfills and Associated Surface Impoundments

1. Based on the results of the corrective measures assessment required in Subsection E of this Section, the permit holder shall select a remedy that, at a minimum, meets the standards of Paragraph F.2 of this Section. Within 180 days after initiation of the corrective measures assessment required in Subsection E of this Section, the permit holder shall submit four bound copies (8 1/2 by 11 inches) of a corrective action plan to the Office of Environmental Services describing the selected remedy, which will meet the requirements of Paragraphs F.2-4 of this Section and be in accordance with LAC 33:I.Chapter 13. The corrective action plan shall also provide for a corrective action groundwater monitoring program as described in Subparagraph G.1.a of this Section.

2. Remedies shall:

a. be protective of human health and the environment;

b. attain the groundwater protection standard as specified in accordance with Paragraph D.8 of this Section;

c. control the source of releases so as to reduce or eliminate, to the maximum extent practicable, further releases of assessment monitoring parameters or constituents into the environment that may pose a threat to human health or the environment; and

d. comply with standards for management of wastes as specified in Paragraph G.7 of this Section.

3. In selecting a remedy that meets the standards of Paragraph F.2 of this Section, the permit holder shall consider the following evaluation factors:

a. long-term and short-term effectiveness and protectiveness of the potential remedy, along with the degree of certainty that the remedy will prove successful based on consideration of the following:

i. the magnitude of reduction of existing risks;

ii. the magnitude of residual risks in terms of likelihood of further releases due to waste remaining following implementation of a remedy;

iii. the type and degree of long-term management required, including monitoring, operation, and maintenance;

iv. short-term risks that might be posed to the community, workers, or the environment during implementation of such a remedy, including potential threats to human health and the environment associated with excavation, transportation, and redisposal of containment;

v. the time until full protection is achieved;

vi. the potential for exposure of humans and environmental receptors to remaining wastes, considering the potential threat to human health and the environment associated with excavation, transportation, redisposal, or containment;

vii. the long-term reliability of the engineering and institutional controls; and

viii. the potential need for replacement of the remedy;

b. the effectiveness of the remedy in controlling the source to reduce further releases based on consideration of the following factors:

i. the extent to which containment practices will reduce further releases; and

ii. the extent to which treatment technologies may be used;

c. the ease or difficulty of implementing a potential remedy based on consideration of the following types of factors:

i. the degree of difficulty associated with constructing the technology;

ii. the expected operational reliability of the technologies;

iii. the need to coordinate with and obtain necessary approvals and permits from other agencies;

iv. the availability of necessary equipment and specialists; and

v. the available capacity and location of needed treatment, storage, and disposal services;

d. the practicable capability of the permit holder, including a consideration of the technical and economic capability; and

e. the degree to which community concerns are addressed by a potential remedy.

4. The permit holder shall specify, as part of the selected remedy, a schedule for initiating and completing remedial activities. Such a schedule shall require the initiation of remedial activities within a reasonable period of time. The permit holder shall consider the following factors in determining the schedule of remedial activities:

a. the extent and nature of the contamination;

b. the practical capabilities of remedial technologies in achieving compliance with groundwater protection standards established in Paragraph D.8 of this Section and other objectives of the remedy;

c. the availability of treatment or the disposal capacity for wastes managed during implementation of the remedy;

d. the desirability of utilizing technologies that are not currently available, but which may offer significant advantages over already available technologies in terms of effectiveness, reliability, safety, or ability to achieve remedial objectives;

e. potential risks to human health and the environment from exposure to contamination prior to completion of the remedy;

f. the resource value of the aquifer, including:

i. current and future uses;

ii. proximity and withdrawal rate of users;

iii. groundwater quantity and quality;

iv. potential damage to wildlife, crops, vegetation, and physical structures caused by exposure to parameters or constituents;

v. the hydrogeologic characteristic of the facility and surrounding land;

vi. groundwater removal and treatment costs;

vii. the cost and availability of alternative water supplies;

viii. the practicable capability of the permit holder; and

g. other relevant factors.

5. The administrative authority may determine that remediation of a release of an assessment monitoring parameter or constituent from a facility is not necessary if the permit holder demonstrates to the satisfaction of the administrative authority that:

a. the groundwater is additionally contaminated by substances that have originated from a source other than a facility, and those substances are present in such concentrations that cleanup of the release from the facility would provide no significant reduction in risk to actual or potential receptors;

b. a parameter or constituent is present in groundwater that is:

i. not currently or reasonably expected to be a source of drinking water; and

ii. not hydraulically connected with waters to which the parameters or constituents are migrating or are likely to migrate in a concentration that would exceed the groundwater protection standards established in Paragraph D.8 of this Section;

c. remediation of the release is technically impracticable; or

d. remediation results in unacceptable cross-media impacts.

6. A determination by the administrative authority in accordance with Paragraph F.5 of this Section shall not affect the authority of the administrative authority to require the permit holder to undertake source control measures or other measures that may be necessary to eliminate or minimize further releases to the groundwater, to prevent exposure to the groundwater, or to remediate the groundwater to concentrations that are technically practicable and that significantly reduce threats to human health or the environment.

G. Implementation of the Corrective Action Programs at Type I and Type II Facilities

1. After the corrective action plan has been approved by the administrative authority and, based on the corrective action plan schedule established under Paragraph F.4 of this Section for initiation and completion of remedial activities, the permit holder shall:

a. implement a corrective action groundwater monitoring program as described in the approved corrective action plan that:

i. at a minimum, meets the requirements of an assessment monitoring program in Subsection D of this Section;

ii. indicates the effectiveness of the corrective action remedy; and

iii. demonstrates compliance with the groundwater protection standard in accordance with Paragraph D.8 of this Section; and

b. implement the corrective action plan established under Subsection F of this Section.

2. A permit holder may submit a report to the Office of Environmental Services demonstrating, based on information developed after implementation of the corrective action plan has begun or other information, that compliance with requirements of Paragraph F.2 of this Section are not being achieved through the remedy selected. A revised corrective action plan providing other methods or techniques that could practically achieve compliance with the requirements of Paragraph F.2 of this Section shall accompany the demonstration.

3. If the administrative authority approves, in writing, the demonstration and revised corrective action plan submitted in accordance with Paragraph G.2 of this Section, the permit holder shall implement the revised corrective action plan.

4. The permit holder may submit a report to the Office of Environmental Services demonstrating that compliance with the requirements of Paragraph F.2 of this Section cannot be achieved with any currently available methods.

5. If the administrative authority approves, in writing, the demonstration submitted in accordance with Paragraph G.4 of this Section, the permit holder shall, within 30 days of the approval, submit a plan to the Office of Environmental Services (which includes an implementation schedule) to implement alternate measures in accordance with LAC 33:I.Chapter 13:

a. to control exposure of humans and the environment to residual contamination as necessary to protect human health and the environment; and

b. for the control of the sources of contamination, or for the removal or decontamination of equipment, devices, or structures, that are technically practicable and consistent with the overall objective of the remedy.

6. If the administrative authority approves the plan for alternate measures submitted in accordance with Paragraph G.5 of this Section, the permit holder shall implement the plan.

7. All solid wastes that are managed in accordance with a remedy required in Subsection F of this Section, or an interim measure required in Clause D.7.a.iii of this Section, shall be managed in a manner:

a. that is protective of human health and the environment; and

b. that complies with applicable RCRA requirements.

8. Remedies selected in accordance with Subsection F of this Section shall be considered complete when:

a. the permit holder complies with the groundwater protection standards established in Paragraph D.8 of this Section at all points within the plume of contamination that lie beyond the groundwater monitoring well system established in Subsection A of this Section; and

b. compliance with the groundwater protection standards established in Paragraph D.8 of this Section has been achieved by demonstrating that concentrations of assessment monitoring parameters or constituents have not exceeded the groundwater protection standard for a period of three consecutive years using the statistical procedures and performance standards in Paragraph B.6 of this Section. The administrative authority may specify an alternative length of time during which the permit holder shall demonstrate that concentrations of the assessment monitoring parameters or constituents have not exceeded the groundwater protection standard, taking into consideration:

i. the extent and concentration of the release;

ii. behavior characteristics of the hazardous parameters or constituents in the groundwater;

iii. accuracy of monitoring or modeling techniques, including any seasonal, meteorological, or other environmental variabilities that may affect the accuracy; and

iv. the characteristics of the groundwater; and

c. all actions required to complete the remedy have been satisfied.

9. Upon completion of the remedy, the permit holder shall submit to the administrative authority, within 14 days, a certification that the remedy has been completed in compliance with the requirements of Paragraph G.8 of this Section. The certification shall be signed by the permit holder and approved by the administrative authority.

10. When, upon completion of the certification, the administrative authority determines that the corrective action remedy has been completed in accordance with the requirements of Paragraph G.8 of this Section, the permit holder shall be released from the requirements for financial assurance for corrective action in LAC 33:VII.1305.

La. Admin. Code tit. 33, § VII-805

Promulgated by the Department of Environmental Quality, Office of Solid and Hazardous Waste, Solid Waste Division, LR 19:187 (February 1993), amended by the Office of the Secretary, LR 24:2250 (December 1998), amended by the Office of Environmental Assessment, Environmental Planning Division, LR 26:2521 (November 2000), amended by the Office of the Secretary, Legal Affairs Division, LR 31:2490 (October 2005), LR 33:1077 (June 2007), LR 33:2152 (October 2007).

AUTHORITY NOTE: Promulgated in accordance with R.S. 30:2001 et seq., and in particular R.S. 30:2154.