Underground Storage Tank Ordinance No. 4332

Attachment "A"

General Requirements for Underground Storage Construction Activity & Soil Investigation

EROSION CONTROL

One or more of the following options shall be utilized to control erosion and contaminant migration during underground tank closure activities (removal, installation, repair, and modification) and/or any soil investigation activities:

1. Excavated soils shall be placed on a paved area. Two rows of baled hay shall be positioned around the entire base of the spoils pile and be configured to provide filtration of any runoff escaping from the spoils pile.

2. Excavated soils shall be placed on a paved area and a non-woven filter fabric fence shall be placed around the base of the spoils pile. The fencing material shall be appropriately keyed in at the base such that any runoff from the spoils pile shall be adequately filtered.

3. Excavated soils shall be placed on a paved area and covered with visquine to prevent any precipitation from coming into contact with the spoils pile.

4. Excavated soil shall be placed on visquine with the edges of the visquine secured over the bales of hay to create a lined containment pool for temporary storage of the excavated soils.

5. The excavated soils shall be immediately loaded into a dump truck and transported to an approved disposal site or treatment facility.

SITE SAFETY

1. All open excavations shall be adequately fenced.
2. All open excavations shall be shored or sloped to prevent the accidental collapse of the excavation, as applicable, in accordance with Subpart P of 29 CFR Part 1928.
3. There shall be no smoking or other sources of ignition on the job site.
4. A minimum of one 20BC rated fire extinguisher shall be provided on the job site.
5. All employees involved with underground storage tank/hazardous waste activity are subject to the health and safety training requirements specified in 29 CFR 1910.120.

LICENSES

1. All contractors removing or installing underground storage tanks shall have a Hazardous Materials certificate and one of the following California State Licenses:

• General "A"
• Limited Specialty C-61 / D 40
• General Building "B" (Only if a structure is involved)

2. Technical reports/documents/plans which contain engineering, geology, and/or geophysical information must be prepared by or under the direction of individuals licensed by the State of California, pursuant to Sections 6735, 7835, and 7835.1 of the Business and Professions Code, as well as Section 19031 of Title 14 California Code of Regulations. One or more of the following California registrations are included:

• Registered Geologist
• Registered Geophysicist
• Certified Engineering Geologist
• Registered Civil Engineer
• Registered Environmental Assessor

LAKE TAHOE WINTER RESTRICTION

Permits for all types of underground storage tank construction (within the Lake Tahoe Basin only) shall not be issued during the period of time from October 16 through April 30 of any year, unless a site specific emergency condition is declared by the Tahoe Regional Planning Agency and the Lahontan Regional Water Quality Control Board.

(Revised 03-01-00)

Attachment "B"

General Requirements for Underground Storage Tank Closure
(Removal or Closure in Place)

INSPECTIONS

The El Dorado County Environmental Management Department must be present to witness the extraction of the tank or closure in place, and all associated sampling activities. All inspections to witness UST closure activities must be scheduled with this agency a minimum of three days in advance. 

PERMITS

Underground storage tanks shall not be closed until a valid permit is issued by this agency. The Lake Tahoe basin shall require approval from the Tahoe Regional Planning Agency, as well, prior to any site work.

PROCEDURES

1. Preparation-

Prior to commencing any site work, all utility lines shall be located and properly marked.
Evacuate all fuel from the product lines for proper disposal. Ensure the tank system is properly prepared and free of appurtenances for removal. Use only non-sparking tools for this work.

2.Tank Cleaning -

• Remove all product/waste from the bottom of the tank using an explosion proof pump that is properly grounded and bonded.
• Ensure the tank is triple rinsed with an inert substance to remove the remaining sludge and/or scale from the interior of the tank.
• The rinseate generated from the triple rinsing process must be handled in accordance with all applicable California hazardous waste disposal laws (i.e. disposed of at an authorized facility under proper manifest procedures by a transporter licensed in the State of California). The rinseate may be stored on site in an DOT approved 55 gallon drum for 7 days only.

3.Tank Inerting -

The inerting process replaces the oxygen and some of the flammable vapors within the tank with an inert gas, such as carbon dioxide, using the following procedure:

• "Dry ice" shall be placed into a clean tank at a minimum ration of 3 pounds per 100 gallons of tank volume. All dry ice shall be evenly distributed over the tank bottom.
• The goal of inerting is to reduce the level of oxygen in the tank to 10% or less. A meter reading of 6-7% oxygen is considered safe.
• All openings on the tank shall then be tightly sealed, except for a 1/8 inch vent hole in a bung cap to allow for temperature expansion.

CAUTION: The atmosphere within the tank may reach the explosive limit again after initially being inerted. Therefore, an approved and properly calibrated hydrocarbon detector with an oxygen meter shall be utilized on site.

Closure-In Place Tanks - At this stage the tank system may be Closed-In-Place by completely filling it with an inert material, such as sand or concrete. Prior to Closure-In-Place activities, you must demonstrate that the tank system has not had an unauthorized release. This is accomplished by providing evidence of clean soil/ groundwater samples from soil borings collected beneath the tank system. Reference Attachments C, D, and the soil/groundwater sampling procedures identified below. All soil/groundwater sampling must be approved by this agency.

4.Tank Extraction -

• Adequately remove the backfill from around the tank. All excavated materials suspected of any contamination, as detected by analysis, instrumentation, odor, or discoloration, shall be excavated and separately stockpiled on site in accordance with all erosion control guidelines identified in Attachment A.
• Utilizing adequate heavy equipment and safety precautions, the tank shall then be removed from the excavation to a secure inspection area. Tanks should not be dragged at any time. A representative of this agency shall examine the tanks for signs of leakage and structural integrity.

5. Tank Disposal -

The California Department of Toxic Substances Control considers excavated tanks which held a hazardous material to be hazardous waste. Therefore, the handling and treating of these tanks must be in accordance with all applicable hazardous waste regulations (e.g. storage, transportation, manifesting, and treatment).

6. Soil Sampling -

• All routine underground storage tank closures shall require analytical results of soil samples collected from the excavation in accordance with Attachment C.
• The number and location of samples shall be performed in accordance with Attachment D or otherwise, depending on site conditions.
• Samples are to be taken immediately after the removal of the tank using a clean stainless steel or brass cylinder that has been properly prepared by an approved party. The sampling cylinder must be at least three inches in length by one inch in diameter. If samples cannot be safely collected from within the excavation, a piece of heavy equipment may be utilized to obtain a segment from the native soil/backfill interface. About three inches of soil should be removed from the immediate surface area where the sample is to be taken. Thereafter, the cylinder shall be pounded into the soil with a wooden mallet. After sample collection is complete, each end of the cylinder shall be covered with teflon and then capped with a polyethylene lid, taped, and properly labeled. The cylinder containing the soil sample shall then be immediately placed into an ice chest containing ice and kept chilled until delivered to the laboratory for analysis.
• Samples shall be analyzed, under strict chain-of-custody, by a laboratory certified by the California Department of Health Services.

7.Groundwater Sampling -

• If groundwater is encountered in the excavation, both soil and groundwater samples shall be required. Groundwater samples shall be analyzed in accordance with Attachment C.
• The number and location of samples shall be performed in accordance with Attachment D or otherwise, depending on site conditions.
• The groundwater samples shall be collected in clean volatile organic analysis (VOA) vials. The liquid shall be completely filled to the top of the vial in such a manner that no air bubbles are entrapped. The VOA sample shall then be place into an ice chest containing ice and kept chilled until delivered to the laboratory for analysis.
• Samples shall be analyzed, under strict chain-of -custody, by a laboratory certified by the California Department of Health Services.

8.Analytical Results -

Upon completion of sample analysis, all test results shall be submitted to this agency within seven (7) days. Any person, owner of real property or authorized agent shall immediately report, upon discovery or receipt of notification, any release or threatened release of a hazardous material to this agency. A complete written report shall be submitted to this agency within five (5) working days of discovery or receiving knowledge of a release.

9.Soil Disposal / Treatment -

• All excavated material and soil suspected of contamination, as detected by analysis, instrumentation, odor, or discoloration, shall be excavated, separated, and stockpiles on the site in accordance with Attachment A.
• All contaminated material and soil must be transported to an approved storage, disposal, or treatment facility in accordance with all Federal, State, and local requirements.
• All contaminated material and soil containing a Total Petroleum Hydrocarbon (TPH) level equal to or greater than 1000 parts per million (ppm) shall be transported by a licensed hauler, under manifest, to an approved storage, disposal, or treatment facility in accordance with all Federal, State, and local requirements.

10.Soil / Groundwater Investigation -

A subsurface investigation to determine the vertical and lateral extent of possible petroleum contamination in the soil and/or groundwater at or in the vicinity of the site shall be required under the following conditions:

• A tank failure is evident (e.g. a hole in the tank and/or piping is noted or saturated soil/groundwater conditions are observed).
• Evidence of soil/groundwater contamination, verified by analytical results.

All interpretation of analytical results and protocol for soil/groundwater investigations will be conducted utilizing guidance documents issued by the State Water Resources Control Board, the Regional Water Quality Control Boards, and the California Department Toxic Substances Control.

(Revised 03-01-00)

Attachment "C"

Soil & Groundwater Analysis Protocol 

*OXYGENATE COMPOUNDS:

TBA(Tertiary Butyl Alcohol), MTBE (Methyl tertiary Butyl Ether), DIPE (Di-isopropyl Ether), ETBE (Ethyl Tertiary Butyl Ether), TAME (Tertiary Amyl Methyl Ether), and Ethanol. Testing for oxygenate constituents may be required for closure of any contaminated site. 

ANALYSIS PROTOCOL -

TETRAETHYL LEAD (TEL) may be analyzed as total lead. However, a confirmation soil sample must be completed from another borehole at the same depth of the original sample or from a groundwater sample from an up gradient well that is not contaminated with hydrocarbons.

CHLORINATED HYDROCARBONS (CL HC) AND BENZENE, TOLUENE, ETHYL BENZENE, AND XYLENE (BTEX) are analyzed in soil by EPA method 8021. EPA method 8260 is used to analyze water.

OIL & GREASE (O & G) may be analyzed by EPA method 418.1. 

NOTES: Fused capillary columns are preferred, as opposed to packed columns. A packed column may be used as a "first cut" with "dirty" samples or once the hydrocarbons have been characterized and proper QA/QC is followed.

For Drinking Water Sources, EPA recommends that the 500 series methods for volatile organics is used, as opposed to the 600 series. The detection limits are and the quality of QA/QC is better with the 500 series.

For all analysis identified on Attachment D, appropriate standards are to be implemented based on the material stored in the tank during the history of its use. Therefore, it is important to consider the different materials that have been stored in the tank and select the analytical methods accordingly.

Other methodologies may be used to complete analytical tests as they become approved by EPA or DHS. Verify proposed methods with this agency, prior to having analytical completed.                            
                                        

Attachment "D"

Sampling Protocol

The following information regarding sampling activities contains general guidelines. All sampling activities are subject to conditions identified during field activities.

WATER NOT PRESENT IN TANK EXCAVATION

1. Samples shall be taken one to two feet below the excavation at the worst-case locations.  
2. If areas of obvious contamination are observed, including any excavated material, they must be sampled and analyzed.

Water not present in tank excavation 

WATER PRESENT IN THE TANK EXCAVATION

1. The tank pit may be purged and allowed to refill before sampling. The purged water is to be disposed of properly at an approved facility.
2. The water sample is to be representative of water in the tank excavation.
3. If areas of obvious contamination are observed, including any excavated material, they must be sampled and analyzed.

Water present in the tank excavation