Current through November 25, 2024
(1) APPLICABILITY.
This section is applicable to all new, expanded or modified land treatment
systems receiving liquid wastes, by-product solids and sludges from industrial
facilities for which a plan approval under s.
281.41, Stats.,
and ch. NR 108 or a WPDES discharge permit under ch. 283, Stats., is required.
It is also applicable to those existing dischargers which need to demonstrate
according to s.
NR 214.06(1) that their land treatment
system complies with groundwater protection requirements although the system
does not meet each specific design standard.
(2) PROFESSIONAL QUALIFICATIONS. The
department shall accept soil test pit evaluations, soil classifications and
soil boring logs performed by a qualified soil scientist, engineer or other
qualified individual. Qualifications shall include a degree from an accredited
institution of higher education or field experience in soil investigation,
interpretation and classification.
(3) TECHNICAL PROCEDURES. All technical
procedures used to investigate a wastewater disposal facility shall be the
current standard procedures as specified by the American society for testing
and materials, United States geologic survey, standard methods for the
examination of water and wastewater, or other equivalent or appropriate methods
approved by the department. Test procedures used shall be specified. Any
deviation from a standard method shall be explained in detail with reasons
provided.
(4) SOIL EVALUATIONS FOR
LANDSPREADING AND SLUDGE SPREADING SYSTEMS. The following soil related
information shall be submitted for sludge spreading systems or landspreading
systems for liquid waste or organic by-product solids:
(a) Individual treatment site locations
identified on topographic maps, plat maps or aerial photographs,
(b) Relevant, existing soil survey
information such as that assembled by the U.S. department of agriculture, soil
conservation service including the soil names, percent slope, relative
permeability, available water capacity, organic matter content and current land
use,
(c) A detailed soils map
displaying the location of the various soils on the site at a scale of not more
than 2,000 feet to the inch,
(d)
Laboratory determined or estimated soil cation exchange capacity,
(e) Agronomic soil nutrient testing results
for making fertilizer and liming recommendations for cover crop growth using
procedures such as those employed by the university of Wisconsin - cooperative
extension program,
(f) Additional
soil related information that may be required by the department on a
case-by-case basis.
(5)
TREATMENT SYSTEMS WHERE GROUNDWATER MONITORING WELLS ARE NOT REQUIRED. For
absorption pond, ridge and furrow, spray irrigation, overland flow and
subsurface absorption systems where groundwater monitoring wells are not
required, or for those sites which are being investigated for potential future
use as such systems, the soils evaluation shall contain the following
information and investigation, at a minimum:
(a) The location, soil survey, soil cation
exchange capacity and soil nutrient content information as specified for
landspreading systems in sub. (4).
(b) A sufficient number of soil test pits
shall be excavated to adequately define the soil conditions found on the site.
1. Prior to soil test pit construction, the
treatment site owner or operator and the department shall agree on the number
and location of test pits to be excavated dependent upon the size of the land
treatment site and uniformity of soils and geology.
2. The soil test pits shall be large enough
to allow visual inspection and documentation of soil layers and shall be
excavated to a depth of 5 feet below the final base grade of the system. The
U.S. occupational health and safety administration requires that test pits with
more than 5 feet of standing wall shall not be entered unless provision is made
to prevent caving of the walls.
3.
The department shall be notified at least 24 hours prior to excavation of the
soil test pits to allow inspection by department personnel.
(c) Soil samples from the test
pits shall be collected and analyzed at each significant change in soil
characteristics or lithology for the following:
1. Soil textural classification in accordance
with the unified soil classification system as specified in ASTM standard
D-2487-85.
2. Particle size
analysis performed in accordance with ASTM D422-72 to determine particle size
distribution. With department approval, soil samples may be composited, or the
particle size determined by a sieve analysis to reduce repetitive testing of
similar soil samples.
3. The soil
moisture holding capacity by direct measurement or as specified through
reference to literature values for different soil textures.
(d) Following soil sample
collection, the test pits shall be deepened to the extent practical with a
backhoe to check for bedrock, the water table or for soil layers that would
restrict the downward movement of water. This shall be visual check from the
land surface, unless the test pits are protected from caving in accordance with
U.S. occupational safety and health administration requirements. All soil test
pits shall be refilled with excavated material following deepening for the
bedrock, water table and impervious layer check.
(6) TREATMENT SYSTEMS WITH REQUIRED
GROUNDWATER MONITORING. For land treatment systems where groundwater monitoring
wells are required, the soils evaluation shall contain the following
information and investigation, at a minimum:
(a) A preliminary site investigation report
shall be assembled that contains the site location, soil survey, soil cation
exchange capacity and soil nutrient content information as specified for
landspreading systems in sub. (4). Also, a limited number of test pits may be
constructed to provide preliminary soils information, such as that specified in
sub. (5).
(b) The treatment system
owner or operator shall submit the results of the preliminary site
investigation and propose a full scale treatment site investigation
plan.
(c) The full scale treatment
site investigation shall consist of a combination of soil test pits and soil
borings to adequately define the soil, groundwater and bedrock conditions at
the site.
1. Prior to construction of test
pits and soil borings, the treatment site owner or operator and the department
shall agree on the number and location of soil borings and test pits dependent
upon the size of the site and uniformity of soils and geology.
2. The soil test pits shall be investigated
as specified in sub. (5).
3. The
soil sampling in borings shall be performed in accordance with ASTM D1586-84 or
ASTM D1587-83.
4. The soil borings
shall extend to the groundwater table, be terminated upon encountering bedrock,
or be drilled to a minimum depth agreed upon in the preliminary site
investigation plan. The department may require the borings to extend to a
minimum depth of 25 feet below the final base grade of the land treatment
system when groundwater or bedrock is not encountered first.
(d) Soil samples which are above
the normal groundwater level and are contained in the unsaturated zone shall be
collected from the test pits and soil borings and analyzed at each significant
change in soil characteristics or lithology as specified in sub. (5) (c).
Hydrogeologic testing requirements are specified in s.
NR 214.21(2)
(e).
(7) HIGH RATE ABSORPTION POND SYSTEMS. For
absorption pond systems having a design hydraulic application rate greater than
10,000 gpd/acre, the minimum soil, groundwater and bedrock related information
and requirements are those listed in sub. (6), with the following additional
requirements:
(a) At least 2 saturated
hydraulic conductivity tests shall be performed on the soils located at the
final base grade of the system using a field permeability test. In some cases,
the department may allow laboratory permeability tests on hydrated and
saturated samples compacted at the same approximate density as exists in the
in-field condition. These laboratory tests may be performed on molded or core
samples, and separate tests shall be performed using tap water, wastewater or
sludge extract. The permeability shall be based on stabilized inflow and
outflow rates during the test. All preparation work and information detailing
the test apparatus shall be submitted along with all results
obtained.
(8) DATA
PRESENTATION. The results from the subsurface investigation shall be presented
in accordance with ch. NR 108 as follows:
(a)
Existing site conditions and surrounding natural and man-made conditions shall
be presented on a baseline topographic map.
(b) Cross-sections shall be developed and
presented to illustrate subsurface geologic and geomorphic conditions. At least
one cross-section shall be developed parallel to groundwater flow. The
cross-sections shall present documented and inferred stratigraphic, soil,
groundwater and bedrock conditions of the site. Soil test pit and soil boring
information shall be correlated to each cross-section developed.
