HomeMy WebLinkAbout20053753.tiff T T T T T 2400 Trade Center Avenue, Ste. 201
Y K 1 K 1 Longmont, Colorado 80503
Renewable Energy, Inc. P: 303.485.0600 F: 303.485.0661
'tit\ www.prairierenew.com
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October 3, 2005
Weld County Planning Department
Weld County GREELEY OFFICE
Department of Planning and Building Inspection
918 10th Street OCT X 5 2005
Greeley, CO 80631 RECEIVED
ATTN: Mr. Kim Ogle
Subject: Proposed Pilot Composting Operation
Dear Mr. Ogle:
Enclosed with this letter of transmittal is our detailed formal proposal dated
September 16, 2005 to build and operate a pilot composting unit at Al Organics'
Rattler Ridge Organic Recycling Facility sited in Weld County. This proposed
pilot will utilize a single anaerobic digester employing Prairie's patented digester
technology.
This proposal is submitted in conjunction with Al Organics and it is our joint
understanding that such a pilot project is permissible under Weld County and
State of Colorado regulations. Neither Prairie nor Al proposes here to amend
the existing Certificate of Designation or Use by Special Review permit for Rattler
Ridge.
We are submitting our proposal to you, to Ms. Cindi Etcheverry of the Weld
County Department of Public Health and Environment and to Mr. Roger Doak of
the Hazardous Materials and Waste Management Division of the Colorado
Department of Public Health and Environment.
We would be pleased to have the opportunity to meet with you and others to
discuss our proposal and to address questions or concerns that you might have.
Since ely, 3ituza
George E. oward
President, rairie Renewable Energy
cc. Bob Yost-Al Organics
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•
• 2400 Trade Center Avenue, Ste. 201
• PRAIRIE Longmont,Colorado 80503
• Renewable Energy, Inc. P: 303.485.0600 F: 303.485.0661
• �'�� www.prairierenew.com
•
• September 16, 2005
•
• Proposed Pilot Anaerobic Composting Digester at the Rattler
• Ridge Organic Recycling Facility
• This submittal by Prairie Renewable Energy, Inc. (Prairie) of Longmont, CO in
• cooperation with Al Organics (Al), is to request authorization to build and
• operate a pilot compost facility using anaerobic digestion at Al's Rattler Ridge
• site located in Weld County on Section 36, R64W, T3N. Weld County has
• previously issued a Use by Special Review permit and Certificate of Designation
(CD) for the Rattler Ridge Organic Recycling Facility and in accord with the
• recommendation of the State of Colorado regarding the CD.
•
This submittal replaces the Prairie/A1 submittal on this subject dated June 21
• 2005 and has been prepared in response to issues raised by Weld County and
• CDPHE. This submittal follows the Colorado Regulations Pertaining to Solid
• Waste Sites and Facilities, 6 CCR '1007-2; it also includes three appendices.
• Appendix A is in Question/Answer format and provides detailed response to
reviewer points and questions. Appendix B provides background information of
• Prairie's digesters and process. Appendix C provides information regarding
• digester liners, including liner repair in case of leakage.
•
• 1. General Data
•
• Names, addresses and telephone numbers of responsible parties:
• Site Owner: Lambland Inc., dba Al Organics
• Address: 16350 Weld County Road 76, Eaton, CO 80615
• Tel 970-454-3492 Fax 970-453-3232
• Contacts: Chuck Wilson — President
Bob Yost—Vice President, New Business Development
•
• Regarding the anaerobic digestion system for the Rattler Ridge site:
• Owner/Operator: Prairie Weld, LLC**
• Address: 2400 Trade Center Avenue
• Longmont, CO 80503
• Tel 303-485-0600 Fax 303-485-0661
• Contact: Dr. George Howard, President— Prairie Renewable Energy
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• ** Prairie Weld, LLC is an affiliate of Prairie Renewable Energy, Inc. (PRI); PRI is
• the developer of the proposed project and holds a 20% interest in Prairie Weld,
LLC. It is requested that any letter from Weld County authorizing this pilot
• composting project to proceed be issued to Prairie Weld, LLC.
• Site maps and drawings
•
• Drawings and diagrams are provided below and in Appendix B to illustrate
• Prairie's process and plans for the pilot composting system at Rattler Ridge. The
• site drawings presented on the next two pages show the location at Rattler Ridge
that will be used for the pilot digester as well as the site layout for a possible build
• out at the location with approximately seventy more digesters. The artist
• rendering following the two site layout pages illustrates the anticipated
• appearance of the pilot composting operation.
•
•
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•
• The figures on the following five pages provide, respectively:
•
• • an elevation view of one digester;
• • a simplified cross sectional view of a single digester;
•
• • a simplified plan view of the Process Building and single digester to show
• the feedstock flow to the digester and the effluent return to the compost
• recovery equipment within the building;
• • a diagram illustrating the digester headworks and flow path;
•
• • a schematic showing how Feedstock Mixing/Heating tanks and other
vessels will be placed in either a bermed area or in a lined pit within the
• building such that spillage of up to 100% of the content of such vessels
• will be confined.
• •
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• 4
•
OVERALL LENGTH
166 FT
HEADWORKS DIGESTER SECTION TAILWORKS
10 FT 150 FT 6FT
DOUBLE MEMBRANE
AIR-SUPPORTED COVER
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SEE DIGESTER SEE DIGESTER TAILWORKS1
HEADWORKS DETAILS DETAILS
DIGESTER ELEVATION
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Weld County Renewable Energy
Digester Cross Section Prairie Renewable Energy
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4Feedstock from
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Process Building
Digester
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Effluent Return to
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Weld County Renewable Energy
Plan View - Piping Connections
A A
Prairie Renewable Energy
4 I 3 Ls 2 1
• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 4
DIGESTATE FEED PIPE
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A A
Weld County Renewable Energy
Berm Containment for Liquid Vessels
Prairie Renewable Energy
4 I 3 4' 2 1 1
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•
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•
• 2. Operations Data:
• Prairie's composting process is very similar to the aerobic composting operations
• currently underway at Rattler Ridge. The primary difference is that anaerobic
• (without air) digestion must be carried out in closed vessels to: (1) exclude
• oxygen which otherwise will kill the naturally occurring bacteria that process the
organics; and (2) capture the biogas (primarily, methane and carbon dioxide) that
• is excreted by the bacteria carrying out the digestion process. The process is
• illustrated in the following figure.
•
• Prairie Renewable Energy, Inc.
• Digester Process Flow}
• --:Green Wasfe,-- .
• -: Manure,Food
"'Wastes,MSW,etc:"-
• —--Y- ______-.-- _-- ______-
• Preprocess -----64 Mixing1Heating j—►•; Pump to =— Debris removed
Digesters
•
• Gas Clearing r Compress Gas 4--- Extract Gas — Fermentation
• (Digestion)
• —
• . De•Water PUmp out
-- Effluent
- i
•
Gas to � --- ----
Customer
• f.%
• — Water High Quality Soil
-------- Amendment
—
• J Recycle Water
• -----
0
• Prairie's high gas yields result from the design and operation of what may be
• thought of as a giant cow stomach, with conditions within the digester being
• carefully maintained at the optimum for biogas production.
• a) Feedstock - the pilot plant will process Types 1, 2 and 3 feed stocks
• that are already permitted for the Rattler Ridge Organic Recycling Facility.
• These feed stocks include but are not limited to: agricultural residues; manure;
. source separated yard, paper and green wastes; food wastes including all types
of brewer's wastes; biosolids; solid waste; sludge's, animal mortalities; and water
• treatment plant residuals.
•
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•
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• b) Bulking materials — no wood or other bulking materials will be needed
• for the pilot anaerobic composting operation.
• c) Anticipated volumes of materials processed and produced - the daily
• amount of Types 1, 2, and 3 feedstocks that will be processed will be
• approximately 18 tons/day (assuming 50% moisture) or not more than 40 cubic
yards per day. The anticipated volume of compost produced by the pilot is not
• more than 30 cubic yards per day.
•
• d) Detailed description of the pilot composting operation consists of the
• following specific procedures and activities:
• • bringing the organic feedstock to the site for the digesters by truck;
•
• • quickly conveying the feedstock into covered and heated mixing tanks
along with water to produce a slurry;
•
• • slow pumping of the slurry into the reinforced concrete head end of the
• digester(s);
• • the simultaneous slow pumping of a reduced-solids slurry out of the back
• end of the digester at a rate identical to the pumping in of feedstock at the
• digester's head end;
1 • processing of reduced-solids slurry to recover and dewater the solids for
• use as finished compost, with the recovered water returned to the process
• for subsequent use to form the feed slurry for the continuing process;
•
• automated control of the process by a computer-driven system
• (Supervisory Control and Data Acquisition "SCADA" system) and including
• instrumentation to maintain very stable environmental conditions
• throughout digester's volume;
• • operation of a circulating water heating subsystem, including a hot water
• heater, for delivering warm water via piping arranged along the side walls
• and bottom of the wedge-shaped digester cross section;
• • extraction of biogas, which is captured between the top of the slurry
• mixture and the lower surface of the inner dome of the digester cover;
•
• • flaring, in accordance with CDPHE air quality regulations and emissions
• permit, of less than 200 cubic feet/minute of biogas production to oxidize
the methane that will be in the biogas and the hydrogen sulfide that may
• be in the biogas, discharging carbon dioxide, water vapor and sulfur
• dioxide.
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gor
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• e) Access control — access to the Rattler Ridge site is via a private road off
• pf Weld County Road 59. This private road is used frequently by Al Organics.
Coors Energy and Waste Management to haul bulk materials. Prairie will install a
• gate to control access to its pilot location at Rattler Ridge and it will only be open
• when the location is manned. Likewise, the locked building for housing the
• control, mixing and other equipment will only be open when manned.
• f) Fire protection plan —fire protection will be provided by the Keenesburg
• volunteer fire department. In addition, Prairie will place pressure-operated fire
• extinguishers at various locations within the facility building that Prairie is
• proposing as part of the pilot composting project.
• g) Storm water run-on and run-off control features design to contain the
• 25-year, 24-hour storm event — the existing Al operation at Rattler Ridges does
• not require run-on, run-off water control features due to the nature of the
geography, soil type and average modest precipitation at the site. Prairie
• proposes to follow Al's approach; however, if needed, a diversion/containment
• berm and or ditches can be constructed around the digester and facility building.
• h) Record keeping — detailed operational records will be kept in the
• planned facility building adjacent to the digester. Prairie will comply with
• requirements for record keeping as outlined by Weld County and the State of
• Colorado in accordance with the requirements of the current Certificate of
• Designation for Rattler Ridge.
• i) Description of work pad — a work pad at the site will be constructed
• utilizing a combination of concrete, native soil and water or similar materials.
• j) Contingency plan addressing actions required in the event of
• unacceptable materials being discovered, contamination or discharge of waters
• from the site occurs, or nuisance conditions occur either on-site or off-site -
• generators of organic materials utilized at the site will be required to certify them
to be non-toxic and non-hazardous. Loads will be visually inspected and
• periodically sampled and tested in according with regulatory requirements.
• Should unacceptable materials be delivered to the site, they will be returned to
• Al for disposal at a properly permitted facility. Should the discharge of waters
from the site occur, the operators will notify the Weld County Health Department
• within five (5) days and consult with its staff on the proper remediation required
• base upon the nature of the event. Nuisance conditions will be dealt with in
• accordance with the most recent operational plan requirements contained in Al's
Certificate of Designation for the Rattler Ridge site.
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• 3. Environmental Issues
• Environmental issues are addressed by reference to the USR and CD issued c.-
• previously to Al Organics for the Rattle Ridge facility. Ick uoly
•
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4. Compost Standards and Quality
•
• Compost standards similar to those utilized now by Al Organics at Rattler Ridge
• will be used. Finished material that meets those standards will be marketed by
• Al as is done with the company's windrowed compost. If any material is
produced that does not meet those standards. Al Organics will consult with the
Weld County Health Department on proper use and disposal of that material.
•
• 5. Closure Plan
•
• If Prairie's pilot compost/digester project is not successful and Prairie does not
• submit for approval of a CD-permanent operation permit, then all feedstock and
post-digestion material will be removed to Al Organics' composting operation at
• Rattler Ridge. Any berms that were constructed will be leveled.
• All instrumentation and other process equipment in the facility building will be
• recovered and removed from the site. If required to do so, or if Al Organics has
no use for the building. Prairie will have the building dissembled and removed
• from the site. If required by Weld County or the State of Colorado, the internal
piping lining the digester, the inner digester liner and digester insulation will be
• removed from the site. The digester 'trench' will be filled with native soil to match
the immediately surrounding contour of the site and the site will be re-seeded per
• requirements of the Weld County agency having jurisdiction.
• 6. Financial Assurance
•
Due to the pilot nature of Prairie's digester facility and the relatively low cost of
• reclamation of the site, Prairie plans to provide financial assurance via a f
reclamation bond or other method acceptable to Weld County. A cost estimate
• for reclamation from a qualified contractor will be obtained prior to issuance of
• the financial assurance.
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• Appendix A: Response to CDPHE and Weld County Questions and
• Points about Digester System Design
•
• This section provides the points raised and question asked (shown in italics)
• followed by Prairie's response.
• 1. Will there be seams in the liner (of the digester)? If so, how will the seams be
• joined together?
• The liners will either be factory-welded (heat fused) into one piece for each
• digester by the liner manufacturer in accord with its Quality Assurance Program
• or will be welded or otherwise assembled in the field by an experienced supplier
• with an established Quality Assurance Program that provides for weld inspection,
sampling and testing.
•
• Polyethylene liners from, for example, Poly-Flex, Inc. are used as basin liners to
• contain the waste stored in waste retention ponds and to prevent surface
precipitation from entering manure and sludge lagoons. Both HDPE (high density
• polyethylene) and LLDPE (linear low density polyethylene) carbon black
• stabilized polyethylene liners are well known for their excellent weather and U.V.
• light exposure resistance, factors that contribute to their reputation for long term
durability. PVC liners and LLDPE liners provide "natural"flexibility for conforming
• to soil profiles and are not as susceptible as HDPE liners to damage during
• installation. Since the liners for the digesters will be protected from the weather
• and sunlight, either PVC or LLDPE liners may also be used. Depending upon
• manufacturer or supplier recommendations, the LLDPE liners can be factory
fabricated (including welding) into a single large piece of sufficient size to
• completely line the digester.
•
One supplier of such "one piece digester liners" is Environmental Protection, Inc.
(http://www.geomembrane.com).
•
• 2. If the liner were to develop a leak, how would this be detected?
• The thermal characteristics of the digester require the space between the two
• liners to be dry. A perforated pipe will be laid at the low point between the liners
• of the pilot digester and be sloped to one end. This pipe will have a continuous
• monitoring system with audible and visual alarm.
• Prairie will also use a sloping layer of gravel under the pilot's outer digester liner
• to funnel any leakage penetrating both liners to one end of the digester. A
• capped small diameter pipe reaching from above the ground surface down into
• the gravel layer (which will rest on a separate length of liner material) will enable
extraction and testing of any liquid for indications of dual liner leakage. Such
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• extraction and testing would normally only be performed on a periodic basis if the
• alarm system showed that leakage had penetrated the first liner. If leakage
through both liners is indicated, Prairie would (1) notify the appropriate State and
• Weld County authorities with 24-hours of external leakage detection and (2)
shutdown the digester, remove its contents and then either repair or replace the
inner liner before digester restart.
• 3. Feedstock delivered by trucks will be unloaded on to Prairie's site. This
• unloading area should be lined and liquids that escape during transfer collected
• and directed to the digester.
• The area will be concrete and be sloped to a sump to assure that any liquids will
• be collected and sent to the mixing tank.
•
• 4. At what point in the (digestion) process is compost tested to ensure
concentrations of metals and pathogens meet the requirements of the solid
• waste regulations?
•
• The compost coming out the digester will be sampled and tested by Al Organics
in accord with Al's approved testing requirements and protocols. Al is also
• responsible for control of materials coming on site. Prairie will also periodically
• take samples of both incoming feedstocks and out going compost for third party
testing. If biosolids are used as feedstock, the resulting compost will treated to
. meet CDPHE's 503 requirements.
• 5. Describe the "desalting" process. Are there wastes generated during the
• process? Is so, how would the wastes be managed?
• Prairie will select commercially available equipment or service to provide for
• periodic removal of salts that may build up in the digester system's recycled
• water. Options include reverse osmosis equipment, absorbents (for example, a
. class of liquid polymer mixing in a tank with the recycled water) and distillation.
With distillation, the salts will be concentrated into a solid form for sanitary landfill
• disposal. With absorbent technology, the salt-loaded absorbent would go to a
• sanitary landfill. With reverse osmosis, the waste product would be a wastewater
• stream with high salt content that would then be treated by absorbents or
distillation or some other method. One supplier of this type of equipment is
Integrated Separation Solutions LLC (www.isepsol.com). US Filter is a supplier
of equipment as well as a service provider with trailer-mounted systems coming
• to customer sites for periodic water cleaning — see
http://www.usfi'ter.com/water/Business+Centers/Mobile_and_On-
• Site Services/Mobile_and_On-
• Site_Services/moss_services_membrane_separation_trailer.htm
•
•
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• 15
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• 6. If the volume of feedstock conveyed to the digester is not entirely used. where
• will the remaining feedstock be stored and how will nuisance conditions be
prevented.
•
• Prairie will only off-load from Al trucks the amount of digester feedstock that
• would go into the digester within a 36-hour period. Any remaining feedstock on
the supply truck would then be delivered to Al's composting operation on the
• Rattler Ridge site. If the off-loaded material was offensive, a cover could be
• placed on it to reduce odor release. If odor for the feedstock after unloading
• becomes a persistent problem, Prairie will construct a covered underground vault
. (or provide a similar solution) that would be opened only when a truck's load was
being delivered to Prairie. The occasional load of liquid/solid of high odor material
• will be pumped into the sealed mixing tank with a few hours.
•
• 7. The plan (an earlier draft) indicates feedstock material remains in the digester
for a period of 12 to 25 days. Is this range feedstock dependent? How is the
• feedstock time in the digester monitored?
•
• Yes, the range of retention times in the digester is feedstock dependent. More
volatile feedstocks, such as food wastes, yield up most of their available methane
• within 10-15 days. If beef feedlot manure is the feedstock, recovery of most of
• the available methane takes longer (about 24 days), based on operation of the
• pilot digester previously tested.
• One method of controlling gas production rates is by using a mixture of
• feedstocks such that there are only minor variations in materials going into the
• digester. This would require addition of several lined trench silos with covers at
• the digester site such that varying feedstocks could be mixed "to a recipe". Daily
monitoring of gas production inside of the digester would reveal accelerations or
• deceleration of gas production and guide changes in retention times, if any were
indicated.
• 8. The digester process flow diagram shows input of multiple feedstocks into the
• digester. How will the system monitor the composting process of varying
• feedstocks to ensure each is composted to reduce pathogens and meet Al's
• compost quality.
• The rate of gas production will provide one form of monitoring of the process
• progress in conversion of the feedstock into methane-rich gas and the "cooking"
• of the feedstock. With the daily discharge of the digester's effluent (which
contains about 6% solids in a water slurry), the solids will be captured by
• dewatering equipment and then delivered to Al's composting operation for
• testing and any additional processing by Al that might be needed to meet
• regulations and Al's quality standard. That additional processing could include,
• among other options, mixing the digester solids in with Al's windrowed materials
and thus raising the digester solids to the temperatures and durations needed to
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• satisfy standards. Alternatively, Prairie may post heat treat the compost before
• releasing it to Al. That heat treatment would utilize the substantial amount of
heat that will be rejected by the Prairie plant's biogas-fired engine-compressors.
• Al would then test the finished compost to verify that requirements were met.
• Please refer to point #18 of the following for clarification.
•
9. During the pilot, the biogas is proposed to be flared. The Air Pollution Control
• Division at the Colorado Dept. of Public Health must review and approve this
• system.
•
Prairie agrees, has started permitting discussions with the Air Pollution Control
• Division and will obtain the needed permit for the shrouded flare equipment.
•
• 10. The "typical digester"cross-section in the April 11, 2005 submittal is listed as
• proprietary information. In the amended May 16, 2005 submittal there is no
proprietary designation for this cross-section. Please clarify.
•
• The simplified cross-section drawing herein is no longer considered proprietary.
• Prairie will separately provide Weld County and CDPHE with a detailed cross
section drawing containing proprietary information. That drawing will be clearly
• marked as PROPRIETARY and Prairie requests that it be suitably protected from
• public disclosure by Weld County and CDPHE.
• 11. The anchor trench illustrated in the cross-section view has no dimensions;
• please provide this information. Also, please provide a drawing showing the
• length of the digester, piping layout to/from digester as well as some details
• about the head works at the feedstock (input) end of the digester as well as the
• effluent section at the other end of the digester.
• These drawings are shown in an earlier section of this report.
•
12. The digester process appears to require a large volume of water, especially
• at startup. Is there an adequate water source at the site?
•
• The pilot compost digester will require up to two acre-feet of water for site
• construction activities and initial charging with water. After that, little water will be
required for process make-up and related operations because the water leaving
• the digester after the digestion is recovered and recycled to the process. The
• required water for the pilot will be provided by Coors Energy from its existing,
• permitted well at its old mining operation located immediately north of the Rattler
Ridge site For the complete Prairie digester complex that is projected to be built
• later at Rattler Ridge, Prairie expects to have a well drilled on the Al site down
• into the Laramie-Fox Hills aquifer after finalizing a water lease agreement with
• Coors Energy, which owns the water rights under the Al site. Coors has agreed
• to obtain the necessary well permit and to provide such water. Negotiations over
a long-term water lease agreement are in progress.
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• 17
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• Approximately 100 acre-feet of water will be needed for full plant construction
and to fully charge the digester complex. After that point, the Prairie plant will
• normally only require make-up, process and sanitation water of perhaps 15 acre-
• feet per year because of recycling of water. Assuming that Prairie processes a
• significant volume of food wastes in the total complex, Prairie can, in fact, be a
• net water producer at Rattler Ridge because much of the high moisture content
in that feedstock can be extracted by the centrifuge separation process expected
• to be used for compost recovery from the dilute effluent stream from the
• digesters.
• 13. A Colorado professional engineer must review and seal all portions of the
• facility design. This would include all drawings submitted as port of the
• operations and design plan. Likewise, any as-built drawings require a Colorado
• PE stamp.
• Prairie is aware of this requirement and such review and approval from a
• Colorado professional engineer will be obtained. Such professional engineers
• compose part of Stantec's staff (Salt Lake City, Ft. Collins, etc.).
• 14. Is the SCADA (Supervisory Control and Data Acquisition system) monitored
• 24/7?
•
The purpose of the SCADA system is to provide continuous computer-based
• monitoring and control of the digester system. This system will be frequently
• queried remotely via modem link by to an offsite computer for any upset condition
• indications. The SCADA system will also provide for a pager signal to go out to
• whomever is on call for an upset event notification and a competent responder
can normally be on site within three hours.
•
• It should be noted that the digester system is quite sluggish in
• developing an upset event. This will allow ample time for a suitable
response to an upset, on the order of days, not minutes. As an
• example, if the hot water heater that provides heating for the
• digester's contents suddenly failed, it would take about 24 hours in
• severe winter weather for the digester's slurry feedstock to cool by
0.5 degrees Fahrenheit.
•
• 15. Page 10 of the May 16, 2005 submittal discusses utilizing the anaerobic
• digester to manage animals during a "biological emergency". The language used
implies that the infected animals could be safely disposed of with this treatment.
• Has this technology been proven to destroy biological infections such as anthrax,
• foot-in-mouth, mad cow?
•
To Prairie's knowledge, such digester destruction of these particular agents has
• not been proven and is considered most unlikely in the case of prions. The
•
•
• 18
•
a
•
10,
•
• digesters would allow for the conversion of macerated animal carcasses into
• methane-rich gas and digester residues. If tests indicated that these residues
were still hazardous, the residues could be further processed to meet regulatory
•
requirements.
•
• 16. and 17. These two points dealt with the organization of this proposal to Weld
• County and State of Colorado to facilitate review by permitting authorities as well
as by interested citizens, as stipulate in Section 14.8 of the solid waste
• regulations 6 CCR 1007-2.
•
• Prairie has prepared this proposal as stipulated in points 16 and 17.
• 18. Will Prairie provide for methane gas and hydrogen sulfide detection at the
• site? If a release were to occur, would we know? How much hydrogen sulfide is
• expected to be generated?
• Yes, continuous monitoring and audible, as well as visual, alarming equipment
• will be installed in the vicinity of the single digester and inside of the small facility
• structure where various handling equipment will be installed. Both Weld County
• and CDPHE authorities will be notified in case of an alarm.
• Since methane is lighter than air, the methane content in any biogas seeping out
• of the digester or other equipment outdoors will rise and pose little danger;
• outside sensors will detect and alarm upon detection of hydrogen sulfide. The
indoor (confined space) detection and alarm system will rely on multiple
• distributed sensors for both methane and hydrogen sulfide and the building will
• have a blower-driven (with explosion proof motor) exhaust system. Prairie will
• also have on-site portable, hand held detection equipment for identifying gas
leakage points requiring service.
•
• It is difficult to predict the amount of hydrogen sulfide that will be produced
• because that depends in part upon the composition of the feedstocks and in part
upon the sulfate content of the well water used in the digestion process. For
• estimating purposes, Prairie has assumed a hydrogen sulfide content of the
• biogas of 300 ppm (parts per million); determining this content is one of the
• purposes of the pilot composting operation at Rattler Ridge. It is expected that
the hydrogen sulfide content of the biogas will be less than 100 ppm. Should
• hydrogen sulfur prove troublesome, Prairie will address the problem by one of
• several means, of which perhaps the simplest would be to pre-treat process well
• water to remove much of the sulfate content of that water.
• As an additional precaution, "NO SMOKING" and other safety signs will be
• prominently posted and no smoking will be permitted on Prairie's site.
•
• 19. What is the nature of the feedstock slurry being supplied to the digester?
•
•
• 19
•
ip
•
•
•
• The various feedstocks will be mixed and heated in a mix/heat tank with water
• added such that the slurry is, nominally, 12% solids by weight. The slurry is then
slowly pumped into the headwork at the input end of the digester. The slurry
• pumped out of the other end of the digester will be, nominally, 6% solid by
• weight. The wetter feedstocks can be mixed with dryer feedstocks to achieve the
• 12% solids slurry.
• 20. How is the mixing required accomplished?
•
• There are a number of common design approaches for providing such mixing.
• Prairie expects to accomplish the mixing by pumping the slurry around a loop of
several vessels (with heating jackets or other arrangement), with the material
• entering the top of each relatively tall vessel and then being pumped out at the
• bottom and going into the next vessel. An alternative is to place a motor driven
• impeller inside the vessels.
• 21. How will the solids pumped out of the digester be recovered as compost?
•
• Prairie will use commercially available solid/liquid separation equipment or
equipment that has completed development. Prairie's plan is to utilize high
• performance centrifuge-based separation equipment to be supplied by ERTH
• Technologies, Inc. (www.erthinc.com) because ERTH's process is substantially
• more effective at recovering solids than competing systems.
• The ERTH Centrifuge (please see figure on following page) separates mixed-
• waste slurry consisting of materials of different specific gravity (most commonly
• solids and liquid) into different flow streams. The ERTH Centrifuge uses two,
• balance-opposed arms that rotate around a center shaft to apply the necessary
G field for separation and can supply up to 2500 G's of acceleration. Flow is
• introduced to the hollow main shaft through a rotary joint, and flows to the two
• arms. As the mixed material flows into the G field in each arm, the more dense
• material is thrown to the end of the arm and is conveyed out through a tube
central to the arm. The less dense material takes a shorter route through the arm
• after the dense material has been separated from it and flows out of the machine.
• The ERTH Centrifuge is based on patented technology and its performance has
• been proven at three different wastewater treatment plants in Colorado.
• 22. Because of potential environmental concerns with fly ash, its use as a
• liner/pad material must be reviewed and approved prior to use.
• Prairie will not use fly ash in the liner/pad for the pilot composting facility. If for
any reason Prairie wishes to use fly ash for some other purpose, Prairie will
• apply to Weld County and CDPHE for appropriate approval.
•
•
•
•
• 20
•
a'
OP
•
•
`. - ,
:-) , '.\ ..-, •- Z-,>--
.ice
• ,% ;-
•
•
• ERTH Centrifuge
•
•
•
• 23. What actions will be taken when the leak detections monitor alarms? Will
• each digester have an alarm and small gravel sump?
• A perforated pipe will be laid at the low point between the liners of the pilot
• digester and be sloped to one end. This pipe will have a continuous monitoring
• system with alarm. Prairie will also use a sloping layer of gravel under the pilot's
• outer digester liner to funnel any leakage penetrating both liners to one end of
the digester. A capped small diameter pipe will extend from above the ground
• surface down into the gravel layer, which will rest on a separate length of liner
• material. This will enable extraction and testing of any liquid for indications of
• dual liner leakage. Such extraction and testing would normally only be performed
on a periodic basis if the alarm system showed that leakage had penetrated the
• first liner.
•• If leakage through both liners is indicated, Prairie would (1) notify the appropriate
State and Weld County authorities within five days and (2) shut down the
• digester, remove its contents and then either repair or replace the inner liner
• before digester restart.
• 24. It is unclear at which point in the process samples will be collected for
• regulatory analyses.
•
• The compost coming out of the digester will be sampled and tested by Al
• Organics in accord with its approved testing requirements and protocols. Al is
•
•
• 21
•
•
•
•
• also responsible for control of materials coming to the Prairie site. In addition,
• Prairie will periodically sample and test samples itself.
• 25. Please provide an abbreviated CQA plan for liner fabrication.
• Appendix C provides the requested information as it relates to factory assembly
and field repair of the liners; liner warranty information is also provided.
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
• 22
•
•
•
•
•
•
•
Appendix B: Prairie Process and Digester Information
•
• The advantages of anaerobic digestion, which necessarily takes place in a gas-
• tight vessel relative to open-air (aerobic) composting of organic waste streams,
are many, including:
•
• • sharp reductions in odor emissions — once the organic feedstock is in the
• digesters, there is no significant odor source;
• • a more rapid conversion of the organic feedstock into a stable and safe
• compost suitable for agricultural, landscaping, land reclamation,
• greenhouse, gardening, turf topping (golf courses, parks, athletic fields,
• etc.) and soil erosion prevention and mitigation control applications;
• • the potential capture of methane gas generated by the anaerobic
• digestion process, which could be delivered in large volumes from a
• multiple digester systems at Rattler Ridge; and,
• • to the extent that manure streams from Concentrated Animal Feeding
• Operations (CAFO's) are processed by the anaerobic digestion system,
• there can be a significant reduction in the release of Greenhouse Gases
• (e.g., methane or nitrous oxide) from this manure that otherwise
contributes to global warming.
•
• It should be noted that methane gas capture and delivery to a gas pipeline
• comprises a sustainable energy resource by supplying 'natural gas' to a US gas
infrastructure.The utilization of this resource is declining due to lower availability
• of gas for residential, commercial, industrial and electric power generation uses.
• Natural gas typically consists of 95% methane.
• It is Prairie's high methane gas yields and sale of that gas that supports the more
• costly anaerobic processing of organic materials. Without the sale or other
• commercial use of that methane, the process is too costly to replace aerobic
• composting.
• Prairie's proposed pilot digester for the Rattler Ridge site consists essentially of a
• specially constructed sealed trench that is some 37 ft in width by about 17 ft deep
• by 150 to 200 ft. in length. The digester is necessarily covered by a double
• polymer dome to contain odors and the generated biogas, and to keep air out of
the digester system because it will impair the digestion process. The outer dome
• will be similar in construction, although lower in profile, to the air-supported
• domes placed commonly over tennis courts or swimming pools in cooler
• climates. Such air-supported structures are long lived and can withstand winds of
100 miles per hour or more.
•
•
• 23
•
•
•
•
•
The inner containment dome will float on the slightly pressurized digester gas
• that forms above the slurry. Warm air or engine exhaust can be fed into the
• space between the inner and outer digester covers to prevent significant heat
• losses to the atmosphere during winter months. The design of the pilot plant will
• include a provision for a small cooling tower in the system to supply cool water to
the digester heating pipes if operating experience shows that summer ambient
• temperatures at Rattler Ridges require such cooling.
•
• The digester is heavily insulated against thermal losses from the heated
feedstock slurry and is double lined with Linear Low Density Polyethylene
(LLDPE) or PVC or other polymer sheeting to ensure that no liquid escapes the
• trench. Prairie expects to construct the digester trench with native soil that has
• been mixed with Portland cement and water to provide strength and stability.
• The native soil will be removed and then replaced in layers ("lifts" in geotechnical
terms) after this mixing to build up the digester walls and the immediately
• surrounding material. This `enhanced soil' approach is a common method of
• earth construction.
• Polyethylene geomembranes from, for example Poly-Flex, Inc., are frequently
• used as basin liners to contain the waste stored in waste retention ponds. Both
• HDPE (high density polyethylene) and LLDPE (linear low density polyethylene)
• carbon black-stabilized liners are well known for their excellent weather and U.V.
light exposure resistance, factors that contribute to their reputation for long term
• durability. PVC liners and LLDPE liners provide excellent flexibility for
• conforming to subgrades, which makes installation easier and improves
• resistance to puncture by rock and other sharps.
• Since the liners for the digesters will be protected from the weather and sunlight
• except during the short construction period, PVC liners may be used in this case.
• Depending upon manufacturer or supplier recommendations, Prairie may elect to
• use PVC or LLDPE liners that are factory fabricated (including welding/joining)
into a single large piece of sufficient size to completely line the digester. One
• supplier of such one piece digester liners that are factory-fabricated in accord
• with the firms Quality Assurance Program is Environmental Protection, Inc.
• (http://www.aeomembrane.com).
• If field joining of liners should be required, only vendors or contractors with
• experience and acceptable joining/welding Construction Quality Assurance
• program will be allowed to perform such welding.
• Depending upon the composition of the feedstock, the feedstock would be fed to
• the digester systems at such a slow rate that some twelve to twenty-five days will
• be required for the feedstock to traverse the full length of the each digester.
•
•
• 24
•
•
•
• For the pilot digester, the resulting biogas delivery rates will be measured to
• verify energy yields and the methane-rich gas mixture will most likely be flared.
The required heat for the pilot digester will most likely be from propane
• combustion in a hot water heater although electric heating could be used. The
• propane is needed until the pilot has been producing biogas in sufficient volume
• that the biogas itself might be used to fire the hot water heater.
• For the multiple digester plant planned for the site to deliver clean methane to
• Duke Energy Field Services, Prairie expects to install biogas engine-driven
• compressors to avoid large consumption of electric power. The rejected heat
from these engine-driven compressors will be partially recovered as needed and
• used to provide the required hot water heating. Propane will be likely be used
• initially to provide the heat needed to 'kick start' the digestion process for the
• multiple units.
• A modest sized process building will be needed to protect operating staff and
• portions of the digester system, such as control system, electronics, some of the
• pumps and mixing vessels, etc., as well as digester residues dewatering
• equipment, from severe weather.
• Should Prairie build a multiple digester system at Rattler Ridge after obtaining
• the necessary permits, the clean methane gas will be delivered to Duke Energy's
• 20-inch pipeline via an existing enclosed 4-inch gas line that traverses the
distance between the Rattler Ridge site and the 20-inch pipeline. This 4-inch line
• with valves is the property of Duke Energy Field Services and is being made
• available for Prairie's use.
• End Products, Waste Products and Disposition
•
• For the pilot digester, the primary product is expected to be high quality compost
• or soil amendment that are the residues from the digestion process, and biogas.
The biogas yields will be measured and combusted in a small, shrouded
• industrial flare at a delivery rate of about 100 cubic feet per minute. The biogas
• will not be scrubbed for methane delivery because the gas volume from a single
• digester is too small for scrubbing to be practical.
• For the multiple digester system, there will be two primary end products, which
• are clean methane gas; and high quality compost. The methane will be sold
• under an existing gas supply contract. The compost from the digestion process
• will be transferred to Al for sales through Al's compost distribution network. The
waste products from the multiple digester system will be a mixture of carbon
• dioxide, a small amount of methane that slips through the biogas cleaning step,
• hydrogen sulfide and water vapor. This waste gas stream is expected to be
• combusted in accord with Colorado air emission regulations, releasing sulfur
dioxide, carbon dioxide and water vapor to the atmosphere.
•
•
•
• 25
•
•
•
•
• All water used in the digestion process will be recovered and returned to the
• process so that very little water should be required after full charging of the
digester(s) upon beginning of operations. From time to time, the recycled water
• may require a `desalting' step to concentrate salts and to then dispose of the
• salts in an approved sanitary landfill. The initial water supply may be pumped
• from the Laramie Fox Hills aquifer via a permitted well at or adjacent to the
• Rattler Ridge site.
•
• Pilot Digester System Energy Supply
• There is a large electrical power substation owned by Xcel Energy at the west
• edge of the Rattler Ridge site that will be tapped for a modest amount of electric
• power for the single pilot digester's operation. This power will be used primarily to
• operate electric motor-driven pumps, motorized valves, the Supervisory Control
and Data Acquisition system (SCADA) that provides automated sensing and
• control, and lighting. As mentioned above, some propane will be consumed
during startup of the pilot digester.
•
• Prairie Renewable Energy
•
• Prairie Renewable Energy, Inc. (Prairie), intends to design, own and operate
"green" energy plants in the USA that use proprietary and patented advanced
• anaerobic digester technology to convert biomass from animal manures, food
wastes, agricultural residues, residential garbage, etc. to biogas. The gas
• produced will be sold under long-term contracts to natural gas gathering,
• transporting and distribution firms and after cleaning of the biogas, it will be
delivered as natural gas to their pipelines.
•
• Prairie's biogas plants will yield significant environmental benefits including: the
• clean up of organic waste concentrations that can negatively impact air and
water quality; the generation of useful energy from renewable resources; and, the
• capture of methane and nitrous oxide that can otherwise slowly evolve to the
• atmosphere from wastes such as animal manures, thereby contributing to global
• warming (methane and nitrous oxide are greenhouse gases with, respectively,
over 20 times and 300 times the greenhouse gas impact of carbon dioxide).
•
• Both economic and regulatory pressures encourage the production of natural gas
• by Prairie's plants. First, the diminishing production of on-shore domestic natural
gas coupled with increased demand has caused an increase of almost 50% in
• natural gas prices over the past year, from approximately $4.80 to over $8.00 per
• MMBtu (million British thermal units) in November 2004 and more currently in
• early June2005 about $6.80. This price history illustrates the high demand in the
• USA for natural gas relative to gas supply. This supply is slowly decreasing and
gas pipelines are slowly going empty.
•
•
26
•
•
•
•
Second, the regulation of odor, as well as other air emissions and threats to
water supplies from animal manures associated with Concentrated Animal
• Feeding Operations (CAFO's) increase the value of Prairie plants. Limits on
• storage, disposal and land application of animal waste increase the
• handling/disposal fees that a Prairie plant can collect by turning the animal
• wastes into energy and organic soil amendment.
• Third, more than 25 states have instituted Renewable Energy Portfolio Standards
• mandating that electric utility companies generate increasing amounts of
• electricity from renewable energy sources, thus boosting the demand and prices
of energy which can be generated by the gas from Prairie's plants.
•
• An additional factor is the concern at county and state levels for a possible
• biological emergency striking CAFO's that will kill or require large numbers of
animals to be put down, such as has happened with anthrax, foot-in-mouth, and
• mad cow infections. The safe disposal of the animal carcasses can be a very
• large problem. Prairie's multiple digester plant planned for Weld County could
• handle as many as 90,000 beef mortalities per month, converting the carcasses
to biogas and then natural gas. Some of the biogas stream could be diverted to
• burn the digester residues to sterilize them if needed for landfill disposal.
•
• The technology at the core of Prairie plants improves existing technology by
• optimizing the conversion process to get increased energy yield from biomass,
thereby reducing capital costs. This allows smaller processing plants to produce
• more energy through novel feedstock preprocessing, as well as monitoring and
• tight control of the anaerobic digesting environment.
• An experienced team composed of members who are well qualified by both
• education and accomplishment has raised initial equity for Prairie, will raise the
• funds needed and is operating the company. Prairie's corporate counsel is
• Rothgerber Johnson & Lyons LLP (Denver, Colorado Springs, Cheyenne,
Casper), one of Denver's largest and oldest law firms. Outside counsel for certain
• investment matters is Bingham McCutchen, LLP of Boston, Washington, D. C.,
• and San Francisco. Prairie's consulting engineering and design firms are:
• Stantec, Inc., a $500 million/year engineering firm based in Edmonton, Alberta
with some forty offices and 4000 employees in North America; and, Selective
• Site Consultants of Overland Park, Kansas, a smaller firm with professional
• engineers registered in over thirty states.
•
•
•
•
•
•
•
• 27
•
S
•
•
Appendix C: Digester Liners
• The following three pages present Quality Assurance information regarding
• factory assembled digester liners, liner warranty information and liner repair
• quality assurance information, all submitted by Environmental Protection, Inc.
(EPI). EPI is the likely vendor for the digester liners.
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
28
•
MP
•
• •
• i Environmental Protection, Inc.
• - 9939 09131 South NE,P.Q.Box 333 Ph 231-587-9108.US 800-OK-LINER
• Mancelona,Michigan 49659-0333 �ax231-687 8020 www.geothembrane.com
THE LINER COMPANY
•
•
Pre-qualification Experience and Quality Control Summary
• Per your request I am submitting the following Information on EPI's Geamembrane liner
• experience and Quality Control information for your review.
• "Enhancing our environment by preserving water resources for future generations." That's the
• mission of Environmental Protection, Inc. For over 25 years that mission has manifested itself in quality
products, fair prices, and commitment to service. Originally created in 1980 to serve the oil industry in
• ritchigan, EPI has expanded into a fug service Geosynthetics suppler having fabricated over 500 million
• square feet of flexible membrane liners. EPI has shipped liners to all 50 states,8 Canadian Provinces,
Met, Chile, Kazakhstan, Bolivia, Morocco,and Saudi Arabia. Whatever the material, we at EPI are
• justifiably proud of our commitment to product quality. All PVC materials meet or exceed standards of
• the PVC Geomembrane Institute (PGI) 1104. 100% of our factory seams are impacted twice before
any liner leaves the factory.A continuous Statistical Process Control(SPC)quality control program and
• systematic analysis of on-site test ponds are two of the many other ways EPI goes to great lengths to
ensure that engineers, regulatory officials, and end-users can act with confidence when selecting EPI
• geomembranes. Be aura to See ourwebstie at www.Geomembrane.com
• EPI's computer network provides for Butted drawing, Inventory and accounting, email and Internet
• access, as well as SPC. EPI'% quality control program utilizes Watcher)testing for PVC, which has
enabled us to produce chemical fusion welds with a 99.97%confidence that all welds exceed minimum
• specifications.
• SPC is also utilized in the production of all other liner materlafe. When thermal welding all types of
• geomembranea,the process is as follows:
• 1. TS welds are made and tested at the beginning of each shift. For example, at the beginning of the
• day and before start-up after lunch.
• 2. A representative sample is made and tested at a rate of one per 3000 lineal feet of seaming
• completed.
• 3. AB scams are visually Inspected to ensure the integrity of the entire liner.
• Please call with any questions regarding EPI's Quality Control Program.
•
• Sincerely,
Brad eArment •
. Environmental Protection, Inc.
bradageomernbrane.com
• 800,655.4637
•
•
.29
•
• zie abed !1V6E:6 90-E-deS odou L85 ice `•Id3 :Au }ue
•
•
•
•
•
• Enviro Liner Adhesive for Patching and Repairing
•
• The Enviro Liner® two part adhesive provides high strength, durable seams for Enviro
Liner@(EL) repairs and modifications.
•
• _= ELsz��eS�«eas pa,f of an,�Ei Rep3! -Kt �vh�ch�2 lu�esone35 ml adhesiu ear[ndoe aria^plLcator — _
gun, mixing nozzles, 8 square feet of EL 30 mil geomembrane, andall required surface preparation
• materials. The kit also includes comprehensive instructions for seaming with EL Adhesive and all
relevant MSDS and product data information. Additional 35 ml adhesive cartridges are also
• available. One 35 ml cartridge of EL Adhesive will provide a seam 1/2"wide and 13 feet long.
• Surface Preparation
• Surface preparation for seaming with EL Adhesive starts with a clean dry surface. Slightly abrade the
surface with a 180 grit or finer abrasive. Sandpaper is included in EL Repair Kit.
•
Seaming with EL Adhesive
• The EL Adhesive tube snaps into place in the applicator gun, instructions for installing the tube are
• included with the applicator. EL Adhesive is a two-part acrylic-based adhesive,the two components
are dispensed from the cartridge in a 10 to 1 ratio, and are mixed in the mixing nozzle. Once the
• adhesive cartridge is in place in the applicator, remove the cap and dispense a small amount of
adhesive to ensure both components are flowing freely. If one of the components is not flowing the
• obstructed opening must be cleared using a needle. Once you are satisfied that both components are
• being dispensed, attach the mixing nozzle and begin seaming.
• The width of the adhesive seam can be varied by adjusting the opening size on the mixing nozzle.
The mixing nozzle as supplied will dispense a bead of adhesive sufficient for a 1/2"seam once the
• two surfaces are damped together. For a wider seam a larger mixing nozzle opening will have to be
• cut using a utility knife.
• Apply a bead of adhesive to one of the surfaces to be bonded and clamp the second surface in place.
The working life of the freshly mixed adhesive is 2.5 to 3 minutes. The two surfaces must be
• clamped together for a period of two hours. Laying a weight such as a sandbag or a metal bar on
• the adhesive seam is an adequate method of clamping.
• Curing
The adhesive will take 8 hours to cure to full strength at an ambient temperature of 73° F. In order
• to accomplish the full cure needed to achieve structural strength there is a low temperature
• restriction of 40° F for using EL Adhesive. Seams attempted below this temperature must include an
external heat source to heat the bond line. For any EL Adhesive seam, heating the bond line to 150°
• - 175° F for 30 minutes will speed the curing time.
• When properly prepared, EL Adhesive seams can attain the same strength specifications (for both
• peel and shear strength) as heat welded field seams.
• Chemical Resistance
The chemical resistance of EL Adhesive has been tested for a number of chemicals. EL Adhesive has
• satisfactory chemical resistance to combustible hydrocarbons such as diesel fuel. If you require
chemical resistance information for a specific chemical it is always advisable to conduct a laboratory
• test. For more information about chemical resistance,or any other information you require about
• the EL Adhesive, please feel free to contact us at 1-800-OK-Liner.
•
•
•
•
•
• 30
•
WSent By: EPI; 231 587 8020; .Sep-7-05 12:54P3; Page 1 /1
Ili. , , -
• The Liner Company
• 99291.15-131 South NE September 7, 2005
timncelona,Mt 49654
• 8f10.nN.LIN6R Mr. George Howard
• nate 231.587.8108 ? .
Prairie Renewable Energy
•-.._ ras �11ei avenue =
wwel.geomembranB.corn Longmonte, CO 80503
•
• Subject: Enviroliner Warranty
•
• Dear Mr. Howard,
•• Per our conversation, this letter is to clarify the warranty for our products.
The Enwiroliner Geomembrane that we have been speaking about for your 'A'
project has a 20 year warranty on it. This warranty covers the material
• against deterioration and normal weather aging for the period of the
• warranty.
• If you need anything more or there is anything more we can do for you,
• please let us know.
• Sincerely,
• P
• Daniel S. Rohe
• President
• c,
•
.1O
: .
rift ,
•
•
•
•
• protecting water resources for future generations
• 31
a
10/04/2002 08:54 7206859706 BOBYOST .� PAGE 02
•
October 4, 2002
�E�AI
P i2tr- .,mom
Pam SmithEnvironmental Solutions • Economic Sense
Weld County Health Department. •
Of Public Health and Environment
1555 N. 17th Ave. - +leis
Greeley, CO 80631
•
Re: Septic Permit#SP0100368,USR 1285 •
Dear Pam, •
Thank you very much for meeting with me and helping to finalize the referenced permit.
As you requested,Ism writing to clarify the permit modifications that were arrived at
during our meeting. They are as follows:
> Drinking water for the scale/office will be provided for via a bottled water source.
> The holding tank that we will install underground for freeze protection will be
used only for restroom use.
➢ There will be signs placed at the holding tank location identifying it and stating
that the water in it is non-potable and not for consumption
> There will also be signagc placed in the restroom regarding the non-potable use as
well-
> we will monitor the water levels in the holding tank manually each week and
keep records for review to insure that water for the restroom is always available.
> The system was engineered for S full time employees and the permit hai been
changed to reflect that fact.
I greatly appreciate the assistance and service you provided me with. Please let me know
if any additional information is required. We plan on having the holding tank installed
quickly so that we can have the restroom up and running before winter sets in.
Sincerel
Bob Yost , •
Vice President,
New Business Development
Cc: Torn Wilson
Chuck Wilson
Cindi Etcheverry,WCDPH&E
• Lunn Facility 16350 WCR 70 • Eaton,Colorado 80615 • Tel 970-4743492•800-7761644•Far 970.454-3232
Lost Antlers Facility 6569 Hwy 93 • Golden,Colorado 80403 • Tel 303-384-9232•Fu:303-384.9259
Raeder Ridge Facility 12002 WCR 39 • Ileetasburg,Colorado 80643
INNIMMr-
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INTEROFFICE MEMORANDUM
TO: JULIE CHESTER-WELD COUNTY PLANNING
FROM: BOB YOST
SUBJECT: MYLAR ON RATTLER RIDGE SITE
DATE: JULY 9, 2001
Julie, here is the final mylar. Please file accordingly. The filing fee has been paid.
Thanks
Bob Yost
Hello