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Grimm's Fuel Company



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Health Impacts

“The exposure to organic dust at workplaces of composting facilities is associated with adverse acute and chronic respiratory health effects, including MMI, chronic bronchitis, and an accelerated decline of FVC%. The pattern of health effects differs from those at other workplaces with exposures to organic dust possibly due to high concentrations of thermo-tolerant/thermophilic actinomycetes and filamentous fungi at composting plants.”
(Bünger et al., 2007)

“Conjunctivitis was diagnosed significantly more often in compost workers. Forced vital capacity in percent of predicted (FVC%) of the non-smoking compost workers declined significantly (-5.4%) during the observation period compared to control subjects. The decline of FVC% in 16 compost workers exceeded 10% of initial values. A significant increase was observed in the number of compost workers suffering from chronic bronchitis (RR = 1.41; 95% CI = 1.28-1.55).”
(Bünger et al., 2007)


“This Community Engagement Plan provides information about Grimm’s Fuel Company’s plans to improve its facility and its commitment to maintaining open communication with the public about its operations.”
(Community Engagement Plan 1/15/2020)

“Specifically, we have developed a framework of commitments and actions to engage the local community and inform them of the operational changes with the composting process at Grimm's Fuel.”
(Jeff Grimm, Letter to Metro 1/15/2020)

When smelling for an odor over a long period of time, the nasal receptors tire or 'blind' to the smell and you become less sensitive. This odor blinding occurred during the turning event on several occasions.” (GMT Report Page 44)

“When smelling for an odor over a long period of time, the nasal receptors tire or 'blind' to the smell and you become less sensitive. This odor blinding occurred during the turning event on several occasions.” (GMT Report Page 44)

“Day 2 of pile sampling blinded the teams noses fairly quickly, making it difficult to determine any kind of reasonable detection limit, after being on the pile for 30 minutes or more.” (GMT Report Page 44)

“Metro is inviting proposals to perform an assessment of composting operations and make recommendations for practice improvements and malodor mitigation at Grimm’s Fuel Company located in Tualatin, Oregon.”
(Metro RFP Page 1)

“Metro is responsible for balancing the business and local community needs with the preservation of yard debris composting capacity in or near the region.”
(Metro RFP Page 1)

“ …the regulator is protecting neighbor comfort and enjoyment as is referenced in many nuisance odor laws. These qualities are simply difficult to define except in the extremes of zero odors or pervasive inundation.”
(GMT Report Page 5)

“ … For the “typical” (non-turning) conditions, substantial impacts (DT ≥ 30), extending out to almost 375 meters (0.25 miles) from the facility under calm conditions. For average wind conditions, dispersion is sufficient to keep DT under 30. These results indicate that the Grimm operations, as currently configured, are having a significant impact in the nearby community.”
(GMT Report Page 53)

“Results of the modeling and field measurements indicate that the Grimm’s facility is inflicting odors on the surrounding community, as far as over 2 miles away, especially under light wind conditions. The modeling indicates that considerable reduction of the pile DT (from over 1000 to down to 30) is needed to reduce the impacts to the nearby community.”
(GMT Report Page 50)

“Strong odors were experienced that were explained by the anaerobic nature of so much organic material. Consequently, the first goal of any compost technology applied to this facility is that it must provide adequate aeration to maintain aerobic conditions throughout at least the active compost phase.”
(GMT Report Page 57)

“Aerated Static Pile (ASP) composting methods use pressure blowers and distribution pipes under the pile to push or pull air through the compost at a rate which typically is based on providing oxygen and controlling the pile temperature. It usually takes five to ten times more air to cool a compost pile than is necessary to provide adequate oxygen to reduce odors and speed up the composting process. ASP systems generally have oxygen levels over 16% within the pile compared to 0 to 5% in static piles and windrows at a 4-foot or greater depth. Air contains 21% oxygen. This higher oxygen level and the removal of excess heat allow ASP systems to be fully aerobic and keep the piles at optimum temperatures (<145° F) if well designed and operated. To meet PFRP they must be insulated with a biocover (usually older compost and overs) and achieve more than 131° F for 3 days throughout the pile. More effective degradation can be achieved through reversing air directions and keeping a relatively consistent temperature within the pile profile.”
(GMT Report Page 13)

“Oxygen levels below the surface never exceeded 10% and commonly were found to be 0.0%”
(GMT Report Page 47)

“A drawback of not having a building is that water will come in contact with compost and under heavy rainfall generate leachate and wet piles. Leachate treatment and storage is not estimated in this cost estimate.”
(GMT Report Page 61)

“The primary goal of this project was to determine approaches to help relieve the burden of odors experienced by Grimm’s nearest neighborhoods.”
(GMT Report Page 62)

“All of the alternatives can and should be operated to maintain oxygen levels within the piles above 10% oxygen”
(GMT Report Page 63)

“Dilutions to Threshold (DT) can be measured using a field olfactometer that filters air from the environment in varying levels to the receptor which is the nose of the person monitoring. The Nasal Ranger manufactured by Saint Croix Sensory is the olfactometer used in this study. While it takes a bit of training and practice to obtain consistent and accurate readings, it can at least produce objective quantified odor intensity measurements, much more cost effectively. The instrument could be used by Metro inspectors either at the pile, or in the neighborhood and at the property line, to measure odor intensity. Nasal Ranger has two sets of cartridges that focus on high or low DT readings. The typical, low DT, measurements are desired for off-site monitoring. If it were determined to be preferable to monitor on top of the unimproved compost pile, the higher DT cartridge would be needed. The higher DTs would not be sufficiently sensitive to provide readings off-site.”
(GMT Report Page 72)

“The highly expanded pile resulting from Fall 2017, needed to be turned in February to be in accordance with Grimm’s normal processing. Grimm’s typically turns the piles only when the wind is from the east to minimize the impact on their closest neighbors to the north and east. The pile had not been turned since September, although much of the volume (including a very large glut of leaves) had been in place only since November. Grimm’s management watched the weather forecasts, and a high pressure system with east winds was predicted for the week of February 5th. Although the system had not fully materialized, the pressure was rising on the 5th, so Grimm’s went ahead and turned the pile, expecting that the winds would come up as predicted. The winds never developed, and the inversion held the entire week, trapping late night and early morning air near the ground surface which greatly concentrated odors experienced by neighbors and others within a larger than typical radius”
(GMT Report Page 23)

(City of Tualatin Resolution No. 3035-94) (CUP-94-11)

“WHEREAS based upon the foregoing Findings of Fact the Council finds that the applicants have provided sufficient evidence to demonstrate that all of the requirements of the Tualatin Developent Code relative to a conditional use have been satisfied and that granting the conditional use for a resource recovery facility is in the best interests of the residents and inhabitants of the City, the applicants, and the public generally.”
(City of Tualatin Resolution No. 3035-94) (CUP-94-11)

“2. The conditional use permit shall be for a resource recovery facility located on Tax Lots 1800 and 1900 of Washington County Assessor’s Map 2S121A. Any expansion of the resource recovery operation onto the properties know as Tax Lots 2100 and 2202 on Assessor Map 2S121A will require conditional use approval.”
(City of Tualatin Resolution No. 3035-94) (CUP-94-11)

“3. The applicant shall conduct the resource recovery operation in the manner that minimizes or prevents dust impacts on the residential areas located north of SW Pacific Drive and on properties in the MP District.”
(City of Tualatin Resolution No. 3035-94) (CUP-94-11)

“4. The applicant shall conduct the resource recovery operation in the manner that minimizes or prevents conditions that produce odor impacts on the residential areas located north of SW Pacific Drive and neighboring properties. These measures shall include procedures for quickly processing yard debris material brought onto the site and managing the size, location, and spacing of compost piles to facilitate mixing and aeration. Fire protection and dust conditions shall also be considered in managing the material piles.”
(City of Tualatin Resolution No. 3035-94) (CUP-94-11)

(City of Tualatin Resolution No. 3419-98) (CUP-97-03)

“WHEREAS, upon the application of Grimm's Fuel Co., a public hearing was open on November 24, 1997, continued to January 12, 1998, and again to March 9, 1998, when the hearing was held to review compliance with the conditions of approval of a Conditional Use Permit (CUP-94-11) to allow a resource recovery facility in the General Manufacturing (MG) Planning District at 18850 SW Cipole Road (2S1 21A 1800 & 1900).”
(City of Tualatin Resolution No. 3419-98) (CUP-97-03)

“Grimm’s Fuel shall construct a permanent water quality facility that meets the SWM [storm water management] requirements and is adequate to serve the Cipole Road site. The facility shall be completed and operational by June 30, 1998.”
(City of Tualatin Resolution No. 3419-98) (CUP-97-03)

“Applicant shall prepare and submit an odor mitigation program that documents existing efforts and identifies how to mitigate future complaints about odor. If there are unresolved odor complaints as verified by City staff, then the City Council may hold a hearing to determine whether the CUP should be allowed to remain as is, be modified with additional conditions, or revoked.”
(City of Tualatin Resolution No. 5072-11) (CUP-11-03)

“Grimm’s has had a significant history of fires and related service calls. Since 2000, TVF&R has responded to the site 71 times. Additionally, as the pile size has grown in recent years the number of fires has grown respectively. 2016 and 2017 were record years for responses at the site … Grimm’s personnel have told us that they have fires on ‘almost on a daily basis’”
(TVF&R Pile Size Appeal Denied 6/20/2018)

“Metro evaluated the information provided by GMT, and in concert with additional feedback from Grimm’s and other local compost operators, released a draft of proposed license conditions for Grimm’s for a 30-day public comment period in October.”
(Metro Staff Report 12/21/2018 Page 3)

“The license must require that the facility operate in a manner that meets the following general performance goals: (1) Environment. It is designed and operated to avoid undue threats to the environment including, but not limited to, stormwater or groundwater contamination, air pollution, and improper acceptance and management of hazardous waste asbestos and other prohibited wastes. (2) Health and Safety. It is designed and operated to avoid conditions that may degrade public health and safety including, but not limited to, fires, vectors, pathogens and airborne debris. (3) Nuisances. It is designed and operated to avoid nuisance conditions including, but not limited to, litter, dust, odors, and noise.”
(Metro Code 5.01.090(c) License Contents)

“As our once rural corner of Washington County becomes urbanized, the composting methods that have served us so well over the last 40 years are no longer suitable.”
(Grimm's Letter to Metro 12/14/2018)

“We have identified 2 places in the receiving area to construct ASP pads in places not currently impacted by the stock pile as shown below. Grimm’s has agreed that they will begin to convert both those areas into functional ASP systems as soon as Metro permits are approved. This can provide 10,000 cubic yards of processing capacity to shorten the composting time to keep the storage requirements minimized.”
(GMT Letter 11/30/2018)

“The licensee must respond to all complaints in a timely manner (including, but not limited to, blowing debris, fugitive dust or odors, noise, traffic, and vectors), and keep a record of these complaints and any action taken to respond to the complaints, including actions to remedy the conditions that caused the complaint. 2. If the facility receives a complaint, the licensee must: (a) Attempt to respond to that complainant within one business day, or sooner as circumstances may require, and retain documentation of its attempts (whether successful or unsuccessful); and (b) Log all such complaints as provided by the operating plan. The licensee must retain each log entry for one year and it must be available for inspection by Metro.”
(Metro License Section 5.13)

“All complaints are recorded on the Complaint Documentation Form. This form documents all pertinent information including the nature of the complaint, date, weather conditions and the name, address and phone number of the complainant. The form also includes findings from the investigation of the complaint and actions taken. Attempts will be made to respond to that complainant within one business day, or sooner. Metro and DEQ will be notified when complaints are received from five different business and/or individuals for the same odor event within one week, or if an odor event lasts longer than 24 hours without resolution or mitigation. Once the cause has been identified, all possible measures are taken to rectify the problem. Completed forms and/or data will be maintained for a period of not less than five years.”
(Grimm's Operating Plan 1/15/2020 Page 7)