CA Health & Safety Code Section 25159.18


Any person who applies to the department for a hazardous waste facilities permit, or for the renewal or revision of a hazardous waste facilities permit, for the discharge of hazardous wastes into an injection well, including any proposed injection well, shall submit a hydrogeological assessment report to the department and to the appropriate regional board six months before making that application. A qualified person shall be responsible for the preparation of the report and shall certify its completeness and accuracy. The department shall not approve the report unless the department finds that the report is current, accurate, and complete, and that no hazardous waste constituents have migrated from the portion of the injection well located above the injection zone or have migrated from the injection zone. The report shall be accompanied by the fee established pursuant to Section 25159.19. The report shall contain, for each injection well, including any proposed injection well, any information required by the department, and all of the following information:

(a)

A description of the injection well, including all of the following:

(1)

Physical characteristics.

(2)

A log of construction activities, including dates and methods used.

(3)

A description of materials used in the injection well, including tubing, casing, packers, seals, and grout.

(4)

Design specifications and a drawing of the well as completed.

(5)

An analysis of the chemical and physical compatibility of the materials used with the wastes injected.

(6)

Annulus fluid composition, level, and pressure at the time of well completion through the present time.

(b)

A description of both of the following:

(1)

The volume, temperature, pH, and radiological characteristics, and composition of hazardous waste constituents placed in the well, based on a statistically significant representative chemical analysis of each specific hazardous waste type, so that any variations in hazardous waste constituents over time are documented.

(2)

The pressure and rate at which fluid is injected into the well.

(c)

A map showing the distances, within the facility, to the nearest surface water bodies and springs, and the distances, within three miles from the facility’s perimeter, to the nearest surface water bodies and springs.

(d)

Tabular data from each surface water body and spring shown on the map specified in subdivision (c), within one mile from the facility’s perimeter, which indicate its flow and a representative water analysis. The report shall include an evaluation and characterization of seasonal changes and, if substantive changes occur from season to season, the tabular data shall reflect these seasonal changes.

(e)

A map showing the location of all existing and abandoned wells, dry holes, mines, and quarries within the facility and within three miles of the facility’s perimeter. The report shall include, for each well shown on the map, a description of the present use of the well, a representative water analysis from any existing wells, any known physical characteristics, and a determination as to whether the well, if abandoned, has been closed in accordance with standards at least as stringent as those set forth in the Department of Water Resources Bulletin No. 74-81, or, if the well is an oil or gas well, in accordance with standards at least as stringent as the regulations of the Division of Oil and Gas. The report also shall include, when possible, the water well driller’s report or well log.

(f)

A map showing the structural geology and stratigraphy within three miles of the facility’s perimeter that can influence the direction of the groundwater flow or the movement of the discharged wastes. The report shall include a description of folds, domes, basins, faults, seismic activity, fractures, and joint patterns, and a geologic cross section and general description of the subsurface rock units, including stratigraphic position, lithology, thickness, and areal distribution.

(g)

An analysis for all of the following:

(1)

The vertical and lateral extent of any water-bearing strata that could be affected by leakage from the injection well.

(2)

The vertical and lateral extent of any strata through which the well is drilled.

(3)

The vertical and lateral limits of the confining beds above, below, and adjacent to, the injection well.

(h)

The analysis specified in subdivision (g) shall include all of the following:

(1)

A map and cross section of all hydrogeologic units.

(2)

Maps showing contours of equal elevation of the water surface for perched water, unconfined water, and confined groundwater required to be analyzed by this subdivision.

(3)

An estimate of the flow, and flow direction, of the water in all water-bearing formations shown on both the maps and the subsurface geologic cross sections.

(4)

An estimate of the transmissivity, permeability, porosity, and storage coefficient for each perched zone of water and water-bearing formations identified on the maps specified in paragraph (1).

(5)

A determination of the water quality of each zone of the water-bearing formations and perched water that is identified on the maps specified in paragraph (1) and is under, or above and adjacent to, the well. This determination shall be conducted by taking samples either upgradient of the injection well or from another location that has not been affected by leakage from the injection well.

(i)

A determination as to whether the groundwater is contiguous with regional bodies of groundwater and the depth measured from the injection zone and well casing to the groundwater, including the depth measured to perched water and water-bearing strata identified on the maps specified in subdivision (h).

(j)

All of the following information for the receiving formation:

(1)

A description of the chemical and physical properties of the receiving formation, including its lithology, thickness, composition, structure, porosity, storage capacity, permeability, compressibility, density, subsurface stress, vertical and lateral continuity and extent, fluid temperature, pressure, composition, and the measurement of the minimum pressure that would fracture the receiving formation.

(2)

The effect of the injection pressure on the receiving formation.

(3)

The geologic stability and long-term integrity of the receiving formation.

(4)

An assessment of compatibility of waste, formation fluids, and formation lithology. This shall include a description of short-range and long-range changes anticipated in the physical and chemical state of the receiving formation in its fluids through chemical reaction and interaction with injection fluids.

(k)

All of the following information for the confining zone:

(1)

A description of its chemical and physical properties, including its age, composition, thickness, vertical and lateral continuity, unconformities, permeability, transmissivity, compressibility, porosity, density, and subsurface stress.

(2)

The minimum amount of pressure that would fracture the confining zone, calculated specifically for the particular confining zone, a description of the number and types of existing fractures, faults, and cavities, and an analysis as to whether fractures were created or enlarged by past injection of wastes.

(3)

The geologic stability and long-term integrity of the confining zone.

(4)

Anticipated short-range and long-range changes in the physical state of the confining zone through chemical reaction and interaction with injection fluids.

(5)

An estimate of the rate of migration of the hazardous waste constituents through the confining zone.

(l)

A geologic cross section and description of the composition of each stratum through which the injection well is drilled. This description shall include a physical, chemical, and hydrogeological characterization of both the consolidated and unconsolidated rock material, including lithology, mineralogy, texture, bedding, thickness, and permeability. It shall also include an analysis for pollutants, including those constituents discharged into the injection well. The report shall arrange all monitoring data in a tabular form so that the dates, the constituents, and the concentrations are readily discernible.

(m)

A description of surface facilities, including, but not limited to, pressure gauges, automatic shutoff devices, alarms, fencing, specifications for valves and pipe fittings, and operator training and requirements.

(n)

A description of contingency plans for well failures and shutdowns to prevent migration of contaminants from the well.

(o)

A description of the monitoring being conducted to detect migration of hazardous waste constituents, including the number and positioning of the monitoring wells, the monitoring wells’ distances from the injection well, the monitoring wells’ design data, the monitoring wells’ installation, the monitoring development procedures, the sampling and analytical methodologies, the sampling frequency, and the chemical constituents analyzed. The design data of the monitoring wells shall include the monitoring wells’ depth, the monitoring wells’ diameters, the monitoring wells’ casing materials, the perforated intervals within the well, the size of the perforations, the gradation of the filter pack, and the extent of the wells’ annular seals.

(p)

Documentation demonstrating that the monitoring system and methods used at the facility can detect any seepage, including any leaks, cracks, or malfunctions in the well or a breach of the confining zone, before the hazardous waste constituents migrate from the well above the injection zone or from the confining zone. This documentation shall include, but is not limited to, substantiation of all of the following:

(1)

The monitoring system is effective enough, and includes a sufficient number of monitoring wells in the major water-bearing zones, which are located close enough to the injection well casing and to the injection zone, to verify that no lateral and vertical migration of any constituents discharged into the well is occurring outside of the injection zone.

(2)

Monitoring wells are not located within the influence of any adjacent pumping wells that might impair their effectiveness.

(3)

Monitoring wells are only screened in the aquifer to be monitored and are monitored for both pressure and water quality.

(4)

The chosen casing material does not adversely react with the potential contaminants of major concern at the facility.

(5)

The casing diameter allows an adequate amount of water to be removed during sampling and allows full development of the monitor well.

(6)

Monitoring wells are constructed so as not to provide potential conduits for migration of pollution, and the wells’ construction features, including annular seals, prevent pollutants from migrating up or down the monitoring well.

(7)

The methods of water sample collection require that the samples are transported and handled in accordance with the United States Geological Survey’s “National Handbook of Recommended Methods for Water-Data Acquisition,” which provides guidelines for collection and analysis of groundwater samples for selected unstable constituents and any additional procedures specified by the department. For all monitoring wells, except those extending into the injection zone, the sample shall be collected after at least five well volumes have been removed from the well.

(8)

The hazardous waste constituents selected for analysis are specific to the facility, taking into account the chemical composition of hazardous wastes previously discharged into the injection well. The monitoring data shall be arranged in tabular form so that the date, the constituents, and the concentrations are readily discernible.

(9)

The frequency of monitoring is sufficient to give timely warning of migration of hazardous waste constituents so that remedial action can be taken prior to any adverse changes in the quality of the groundwater.

(10)

A written statement from the qualified person preparing the report indicating whether any constituents have migrated into the surface water bodies or any strata outside the injection zone, including water-bearing strata.

(11)

A written statement from the qualified person preparing the report indicating whether any migration of hazardous waste constituents into surface water bodies or any strata outside the injection zone, including water-bearing strata, is likely or not likely to occur within five years, and any evidence supporting that statement.

(q)

This section applies only to injection wells into which hazardous waste is discharged.
Last Updated

Aug. 19, 2023

§ 25159.18’s source at ca​.gov