Section 784.14. Hydrologic information

(a) Sampling and analysis. All water quality analyses performed to meet the requirements of this section shall be conducted according to the methodology in the current edition of "Standard Methods for the Examination of Water and Wastewater," which is incorporated by reference, or the methodology in 40 CFR Parts 136 and 434. Water quality sampling performed to meet the requirements of this section shall be conducted according to either methodology listed above when feasible.

(b) Baseline information. The application shall include the following baseline hydrologic information, and any additional information required by the division.

(1) Groundwater information. The location and ownership for the permit and adjacent areas of existing wells, springs, and other groundwater resources, seasonal quality and quantity of groundwater, and usage. Water quality descriptions shall include, at a minimum, total dissolved solids or specific conductance corrected to 25°C, pH, total iron, and total manganese. Groundwater quantity descriptions shall include, at a minimum, approximate rates of discharge or usage and elevation of water in the coal seam, and each water-bearing stratum above and potentially impacted stratum below the coal seam.

(2) Surface water information. The name, location, ownership and description of all surface water bodies such as streams, lakes, and impoundments, the location of any discharge into any surface water body in the proposed permit and adjacent areas, and information on surface water quality and quantity sufficient to demonstrate seasonal variation and water usage. Water quality descriptions shall include, at a minimum, baseline information on total suspended solids, total dissolved solids or specific conductance corrected to 25°C, pH, total iron, and total manganese. Baseline acidity and alkalinity information shall be provided if there is a potential for acid drainage from the proposed mining operation. Water quantity descriptions shall include, at a minimum, baseline information on seasonal flow rates.

(3) Supplemental information. If the determination of the probable hydrologic consequences (PHC) required by subsection (e) of this section indicates that adverse impacts on or off the proposed permit area may occur to the hydrologic balance, or that acid-forming or toxic-forming material is present that may result in the contamination of groundwater or surface water supplies, then information supplemental to that required under subdivisions (b)(1) and (b)(2) of this section shall be provided to evaluate such probable hydrologic consequences and to plan remedial and reclamation activities. Such supplemental information may be based upon drilling, aquifer tests, hydrogeologic analysis of the water-bearing strata, flood flows, or analysis of other water quality or quantity characteristics.

(c) Baseline cumulative impact area information.

(1) Hydrologic and geologic information for the cumulative impact area necessary to assess the probable cumulative hydrologic impacts of the proposed operation and all anticipated mining on surface water and groundwater systems as required by subsection (f) of this section shall be provided to the division if available from appropriate federal or state agencies.

(2) If this information is not available from such agencies, then the applicant may gather and submit this information to the division as part of the permit application.

(3) The permit shall not be approved until the necessary hydrologic and geologic information is available to the division.

(d) Modeling. The use of modeling techniques, interpolation or statistical techniques may be included as part of the permit application, but actual surface water and groundwater information may be required by the division for each site even when such techniques are used.

(e) Probable hydrologic consequences determination.

(1) The application shall contain a determination of the probable hydrologic consequences (PHC) of the proposed operation upon the quality and quantity of surface and ground water under seasonal flow conditions for the proposed permit and adjacent areas.

(2) The PHC determination shall be based on baseline hydrologic, geologic and other information collected for the permit application and may include data statistically representative of the site.

(3) The PHC determination shall include findings on:

(i) Whether adverse impacts may occur to the hydrologic balance;

(ii) Whether acid-forming or toxic-forming materials are present that could result in the contamination of surface water or groundwater supplies; and

(iii) What impact the proposed operation will have on:

(A) Sediment yield from the disturbed area;

(B) Acidity, total suspended and dissolved solids, and other important water quality parameters of local impact;

(C) Flooding or streamflow alteration;

(D) Groundwater and surface water availability; and

(E) Other characteristics as required by the division.

(iv) Whether the underground mining activities conducted after October 24, 1992, may result in contamination, diminution or interruption of a well or spring in existence at the time the permit application is submitted and used for domestic, drinking, or residential purposes within the permit or adjacent areas.

(4) An application for a permit revision shall be reviewed by the division to determine whether a new or updated PHC determination shall be required.

(f) Cumulative hydrologic impact assessment.

(1) The division shall provide an assessment of the probable cumulative hydrologic impacts CHIA) of the proposed operation and all anticipated mining upon surface water and groundwater systems in the cumulative impact area. The CHIA shall be sufficient to determine, for purposes of permit approval, whether the proposed operation has been designed to prevent material damage to the hydrologic balance outside the permit area. The division may allow the applicant to submit data and analyses relevant to the CHIA with the permit application.

(2) An application for a permit revision shall be reviewed by the division to determine whether a new or updated CHIA shall be required.

(g) Hydrologic reclamation plan. The application shall include a plan, with maps and descriptions, indicating how the relevant requirements of Part 817 of this chapter, including 4VAC25-130-817.41 through 4VAC25-130-817.43, will be met. The plan shall be specific to the local hydrologic conditions. It shall contain the steps to be taken during mining and reclamation through bond release to minimize disturbance to the hydrologic balance within the permit and adjacent areas; to prevent material damage outside the permit area; and to meet applicable federal and state water quality laws and regulations. The plan shall include the measures to be taken to: avoid acid or toxic drainage; prevent to the extent possible using the best technology currently available, additional contributions of suspended solids to streamflow; provide and maintain water treatment facilities when needed; control drainage; prevent the sudden release of accumulated water from the underground workings; and restore approximate premining recharge capacity. The plan shall specifically address any potential adverse hydrologic consequences identified in the PHC determination prepared under subsection (e) of this section and shall include preventive and remedial measures.

(h) Groundwater monitoring plan.

(1) The application shall include a groundwater monitoring plan based upon the PHC determination required under subsection (e) of this section and the analysis of all baseline hydrologic, geologic and other information in the permit application. The plan shall provide for the monitoring of parameters that relate to the suitability of the groundwater for current and approved postmining land uses, to support the objectives for protection of the hydrologic balance set forth in subsection (g) of this section, to determine the cause of diminution or contamination of usable ground waters, and to guard against off-site influences and provide representation of the effects of the proposed surface coal mining operation. It shall identify the quantity and quality parameters to be monitored, sampling frequency and site locations. It shall describe how the data may be used to determine the impacts of the operation upon the hydrologic balance. At a minimum, total dissolved solids or specific conductance corrected to 25°C, pH, total iron, total manganese, and water levels shall be monitored and data submitted quarterly or as otherwise specified by the division for each monitoring location.

(2) If an applicant can demonstrate by use of the PHC determination and other available information that a particular water-bearing stratum in the proposed permit and adjacent areas is not one which serves as an aquifer which significantly ensures the hydrologic balance within the cumulative impact area, then monitoring of that stratum may be waived by the division.

(3) The monitoring plan shall be designed in accordance with the following subparagraphs. The division may require additional monitoring and the analysis or measurement of other parameters on a site-specific basis. During the mining or postmining phase of activity, the division may require additional monitoring if it is determined that the established monitoring plan is ineffective.

(i) When pH or chemical analysis results indicate no immediate or potential acid-producing or toxic material within the proposed disturbed area, the applicant may submit a plan for representative monitoring. Appropriate monitoring which will indicate changes in subsurface water quality and quantity at sites which provide geological and hydrological representation of the entire proposed permit area shall be established.

(ii) When potential for adverse impacts to ground waters in use exists, then a representative monitoring plan utilizing wells or springs shall be provided.

(iii) When no potential to affect ground waters in use exists, then a plan utilizing piezometers or methods for representative monitoring in the unsaturated zone may be used.

(iv) When structural or stratigraphic variations are present within the proposed permit area, altering the ground water regime and indicating more than one representative area, the applicant shall include within the plan a minimum of one monitoring site for each representative area.

(v) The applicant shall include a plan to source monitor near isolated acid-producing or toxic material using piezometers or equipment for monitoring the unsaturated zone.

(vi) When any portion of a surface mine operation is proposed within a stream floodplain, the applicant shall include a plan for monitoring using wells in alluvial material both upstream and downstream of the proposed area to be disturbed. The plan shall also include adjacent upgradient and adjacent downgradient monitoring wells for any slurry pond with water having a pH of less than 6.0, coal stockpiles, and acid-producing or toxic-producing material disposal site.

(vii) In cases where the alluvium monitored has been determined to be consistently or seasonally unsaturated, the division may require revision of the monitoring plan to include appropriate monitoring of the unsaturated zone.

(viii) Where potential exists for adverse impacts to the hydrologic regime from a surface mining operation situated in an area of colluvium, the division may require monitoring similar to that required in floodplain areas.

(ix) For each refuse or hollow fill without an underdrain, the applicant shall include a plan to monitor the fill using piezometers which are sufficient in number and design to permit a planar determination of a potential water table within the fill.

(x) When a refuse or hollow fill is designed to contain underdrains, then a plan for monitoring the underdrain may be used, provided that the underdrain discharge indicates changes in water quality resulting from the fill and not from other sources or outside influences. If the underdrain is not representative of the effects of the fill material, then piezometers shall be used.

(xi) The applicant may include a plan to use a spring in lieu of other monitoring methods if:

(A) The spring is located both stratigraphically and geographically so that data representing an area to be disturbed or an acid or toxic spoil isolation area will be obtained.

(B) The spring has been observed and documented satisfactorily to the division to be a permanent spring.

(xii) For the adjacent area, the applicant shall submit a plan to individually monitor each significant aquifer identified with wells, springs, mine discharges or any combination of these. The plan shall include flow measurements for each point under seasonal conditions. The division shall require quality analyses in addition to quantity measurements if it determines that such monitoring is necessary for protection of the hydrologic balance.

(i) Surface water monitoring plan.

(1) The application shall include a surface water monitoring plan based upon the PHC determination required under subsection (e) of this section and the analysis of all baseline hydrologic, geologic and other information in the permit application. The plan shall provide for the monitoring of parameters that relate to the suitability of the surface water for current and approved postmining land uses and to the objectives for protection of the hydrologic balance as set forth in subsection (g) of this section as well as the effluent limitations found at 40 CFR Part 434.

(2) The plan shall identify the surface water quantity and quality parameters to be monitored, sampling frequency and site locations. It shall describe how the data may be used to determine the impacts of the operation upon the hydrologic balance.

(i) At all monitoring locations in surface water bodies such as streams, lakes, and impoundments, that are potentially impacted or into which water will be discharged and at upstream monitoring locations, the total dissolved solids or specific conductance corrected to 25°C, total suspended solids, pH, total iron, total manganese, and flow shall be monitored.

(ii) For point-source discharges, monitoring shall be conducted in accordance with 40 CFR Parts 122, 123, and 434 and as required by the National Pollutant Discharge Elimination System permit.

(3) The monitoring reports shall be submitted to the division quarterly. The division may require additional monitoring.

Historical Notes

Derived from VR480-03-19 § 784.14, eff. December 15, 1981; amended, eff. June 28, 1982; October 28, 1982; December 14, 1982; October 11, 1983; December 27, 1983; May 8, 1984; June 22, 1984; August 2, 1984; October 16, 1985; January 7, 1987; July 22, 1987; November 25, 1987; October 12, 1988; December 26, 1990; July 1, 1991; July 17, 1991; November 20, 1991; July 7, 1992; May 5, 1993; October 19, 1994; Volume 13, Issue 11, eff. March 19, 1997; Volume 14, Issue 05, eff. December 24, 1997.

Statutory Authority

§§ 45.1-161.3 and 45.1-230 of the Code of Virginia.