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SOLID WASTE & HAZARDOUS MATERIALS
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Investigation/Remediation & Monitoring Wells
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Site Investigation, Site Remediation,
Monitoring Well and Soil Boring - Permit Requirements
Sites suspected of being contaminated
with hazardous materials/wastes must be investigated to determine
the lateral and vertical extent of any contamination. Sites found
to be contaminated must be remediated. Site investigations and
remediations typically include the collection of soil and water
samples for laboratory analysis. Subsurface water and soil samples
are collected via monitoring wells and soil borings.
El Dorado County Ordinance Code Section
8.38.040 states, "Any person who installs soil borings and/or
monitoring wells, conducts a site investigation, or performs off-site
or on-site remediation shall obtain and keep current a permit
from the Environmental Management Department." To obtain
a permit an applicant must submit an application, work plan, site
map and permit fees. For projects requiring staff time beyond
the hours covered by the permit, additional oversight fees will
accrue at the approved hourly rate.
Requirements for Monitoring Well Installation:
- A permit
application is required to install or abandon a monitoring
well, install soil borings, conduct a site investigation, or perform
on- or off-site remediation.
- All monitoring wells/soil boring/exploratory
boring installations shall conform with existing California Well
Standards for construction and construction materials .
- Prior to drilling, a line-locating service shall
be used to identify any potential drilling obstructions.
- All equipment, drill cuttings, and well development
water shall be temporarily contained in Department of Transportation
(DOT) approved drums on site until lab analysis is complete. Drums
shall be properly labeled and dated. Temporary storage time shall
not exceed 90 days.
- Monitoring wells must be completed at least 12"
above grade with a monument type protection cover. Flush type
vaults shall be used in traffic areas only.
- Each monitoring well must be locked and numbered.
- All equipment used in drilling and sampling activities
must be properly cleaned before and between each use. Chemicals,
glues and solvents shall not be used in the construction of monitoring
wells/soil borings.
- If the site is not ready for a scheduled inspection
appointment, then an additional hourly Department fee may be charged.
- An annual permit fee may be charged and an annual
inspection may be conducted to confirm the status of the monitoring
well.
- Other requirements may apply at the discretion of
this Department. Contact this Department at (530) 621-5300 in
Placerville or (530) 573-3450 in South Lake Tahoe for further
information.
- Contact this agency to schedule a final inspection
with a minimum of 48 hours advance notification.
Requirements for Groundwater Monitoring and
Sampling (M&S)
The El Dorado County Environmental Management Department
maintains oversight of groundwater sampling performed at contaminated
sites within the county. Please be advised that the El Dorado County
Environmental Management Department (EMD) now requires the following:
- At least one week notice of upcoming groundwater
sampling at contaminated sites prior to the date of the M&S
event.
- An SOP-type document included in your M&S reports
that specifically describes how your groundwater monitoring and
sampling activities will be (or were) performed at each site.
- Provide proof of completion of 40-hr HAZ-MAT and
Emergency Response training required and should be available for
inspection by county personnel (29 CFR 1910.120).
- A site-specific and activity-specific Health and
Safety Plan and kept in a prominent location at the site during
field activities. The Health and Safety Plan should be prepared
in accordance with California Code of Regulations Title 8, Section
5192, Part 4, Section (B).
- Please check back for additional site assessment
and remediation information, which will be posted as it becomes
available.
Requirements for Destroying Monitoring Wells and
Soil Borings:
A well is considered abandoned or permanently inactive if it has
been unused for more than one year. Abandoned or permanently inactive
wells must be destroyed in accordance with all relevant sections
of CA Water Code Division 7, Chapter 10, CA Health and Safety Code
Division 104 Part 9.5, and CA Water Well Standards Bulletins 74-81
and 74-90, including the following:
- Prior to destroying a well, it must be investigated
to determine the construction details, maintenance history and
current condition. A work plan including the investigation findings
and destruction method must accompany the permit application.
- Wells must be sounded immediately prior to destruction
to ensure they are free of obstructions. If any chemical contaminants
are observed, Environmental Management Department must be immediately
notified in writing. Wells shall be cleaned to remove and properly
dispose of all obstructions and contaminants.
- For wells constructed and maintained in accordance
with CA standards, casing that is more than 5 feet below ground
surface may be left in place. The casing must be filled with sealing
material up to 5 feet below ground surface. After sealing material
has set, a 5-foot deep hole shall be excavated around the casing
and the casing cut off at the bottom of the hole. The excavation
shall then be filled with clean native soil.
- For wells not constructed and maintained in accordance
with CA standards, all material within the original borehole (annular
seal, casing, screen, filter pack, etc.) must be removed. The
borehole must be completely filled with impervious sealing material.
- Acceptable sealing materials include neat cement,
sand-cement grout, or concrete.
- Sealing material shall be placed by “tremmie”
pipe or equivalent method in one continuous operation. Sealing
pressure must be maintained until sealing materials are properly
set.
- Sealing material may be placed by free fall method
only if the well is dry, less than 30 feet deep and does not result
in bridging or voids. Volume/fill calculation must be completed
to document successful destruction.
- Soil borings must be completely filled with
sealing material up to five (5) feet below grade. Sealing material
may be placed by free fall method only if the boring is dry, less
than 30 feet deep and does not result in bridging or voids. Volume/fill
calculation must be completed to document successful destruction.
Definitions:
Monitoring Well
= Monitoring wells are different in nature from other wells. They
are usually designed to have a shorter life span than other wells,
such as water wells. Monitoring wells are usually used in monitoring
potentially contaminated sites. These wells are almost always associated
with an investigation or clean up of a potentially hazardous material.
Soil Boring
= A soil boring is an uncased artificial excavation constructed
by any method for the purpose of obtaining information on subsurface
conditions or for the purpose of determining the presence or extent
of contamination in subsurface soils or groundwater and for seismic
information.
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