On Monday, Governor Northam signed the Virginia Clean Economy Act which establishes a mandatory renewable portfolio standard to achieve 30% renewable energy by 2030, a mandatory energy efficiency resource standard, and creates the path to a carbon-free electric grid by 2045. This took place as California, a pioneer in large scale solar and wind farms is struggling to keep the power amid inadequate electricity supplies during their current heat wave.
Rolling blackouts across California should serve as a cautionary tale for Virginia as we look to move to a carbon free electric grid. Though solar and wind can generate power without contributing to climate change, they cannot generate power round the clock. Over the past weekend rolling blackouts have swept through California due to inadequate power availability. This shortfall is due in part to demand for power peaking in early evening just as the solar arrays began their evening declines.
Solar and wind supply about of a third of California’s power. Despite still having gas turbines that can supply power at peak demand, California was not able to meet the full demand even with conservation orders. In part this was because California relies heavily on its neighbors- it is a net importer of electricity and the nearby states were also experiencing higher than usual demand. Virginia, too, is a net electricity importer.
This should serve as a cautionary tale for Virginia who is planning to eliminate all fossil fuels from the power grid and use batteries to cover serge demand. The Virginia Clean Economy Act proposes 16,100 megawatts of solar and onshore wind, 5,200 megawatts of offshore wind, and 2,700 megawatts of energy storage and states that they are in the public interest. Large scale batteries have the potential to help during brief periods of power scarcity, but it remains to be seen if the Virginia electric grid can maintain reliability without also mainlining some gas fired power generation. My solar production falls significantly during rainy periods and ceases entirely in the snow.
At the signing Governor Northam said: “Together, these pieces of legislation put the Commonwealth in position to meet the urgency of the climate crisis, and lead the transition to renewable energy in a way that captures the economic, environmental, and health benefits for all Virginians.” Let’s hope so. I lived through the power shortages in California in 2001 (sitting around without heat or electricity in the winter) and do not wish to repeat the experience in my golden years.
The Virginia Clean Economy Act not only establishes energy efficiency standards and new investments in solar, onshore wind, offshore wind, and energy storage, but additional legislation advances shared solar and energy storage programs, and dramatically transforms the rooftop solar market, and increase the allowable size of residential net-metered projects to 25 kwatt. The Governor also signed legislation directing the State Corporation Commission to determine when electric utilities should retire coal-fired or natural gas-fired electric generation facilities, and how utility customers should pay for this transition. I look forward to reading their report.
Thursday, August 20, 2020
Monday, August 17, 2020
2020 PW Drinking Water Clinic is Happening!
Water samples will be tested for: iron, manganese, nitrate, lead, arsenic, fluoride, sulfate, pH, total dissolved solids, hardness, sodium, copper, total coliform bacteria and E. Coli bacteria.
Sample kits will be $65 this year, this is the cheapest way to get this testing done. There are a limited number of test kits and pre-paying online is the only way to purchase them this year. Test kits must be paid for by August 24th online. . Pre-pay online by going to this link.
https://tinyurl.com/PWVCE-2020VAHWQP
The Prince William Drinking Water Clinic has 4 parts:
1. Virtual Kick-Off Meeting. Watch Kick-Off Meeting PowerPoint presentation and How to Collect Water Sample using links below:https://www.wellwater.bse.vt.edu/files/DWC/2020-VAHWQPKickoffPresentation-COVID.ppt
https://www.youtube.com/watch?v=a2wqzuzvbK4:
2. Pick up your sample kit at the Extension office in Manassas with physical distancing measures. They will have a drive-through pick up on Saturday, August 29, 2020 from 9:00 am until noon at the Prince William County Extension Office parking lot located at 8033 Ashton Avenue, Manassas, VA 20109-8202.
4. Samples will be analyzed at Virginia Tech. You will receive your confidential results via email in October. The results will include an explanation of what the results mean, and information about addressing any problems.Results Interpretation Meeting will be held on Zoom on Monday, October 5th, 7:00pm-9:00pm, there will be a live Zoom interpretation meeting which will explain the report, include a discussion, and answer questions on dealing with water problems.
Join Zoom Meeting on October 5th 2020
https://virginiatech.zoom.us/j/99105205328
Meeting ID: 991 0520 5328
Or Join by Skype for Business
https://virginiatech.zoom.us/skype/9910520532
You are responsible for your household water quality. Join the clinic and make you’re your well water is safe to drink. According to the 2018 Annual Report for the Virginia Household Water Quality Program from Virginia Tech, there are 1.7 million Virginians or 22% of the state’s population get their household water from a private well. Municipal water supplies are regulated and regularly tested under the EPA’s Safe Drinking Water Act. Private wells are the responsibility of the well owner. Over 2,000 households have their water tested each year through the Virginia Household Water Quality Program.
The chart below shows what we found in the 101 private wells tested in the first round of testing we did in Prince William County in 2019.
Thursday, August 13, 2020
EPA will Rescind 2016 Methane Regulations
It was widely reported in the press that and anonymous administration official leaked that the U.S. EPA is preparing to release new rules that would rescind regulations from the 2016 New Source Performance Standards (NSPS) for the oil and natural gas industry. The regulations were adopted in 2016 under former President Obama amid the increasing concern for the expansion of the natural gas industry. These new regulations were expected after the U.S. EPA proposed several modifications and opened a comment period last year.
At the time EPA proposed two actions:
At that time EPA Administrator Andrew Wheeler said: “The Trump Administration recognizes that methane is valuable, and the industry has an incentive to minimize leaks and maximize its use. Since 1990, natural gas production in the United States has almost doubled while methane emissions across the natural gas industry have fallen by nearly 15%. Our regulations should not stifle this innovation and progress.”
According to the U.S. EPA, methane is the second most prevalent greenhouse gas and accounted for about 10% of all U.S. greenhouse gas emissions from human activities. Methane is emitted by natural sources such as wetlands and the breakdown of organic material, as well as from leakage from natural gas systems, growing rice, waste disposal and the raising of livestock. However, as you can see on the right, the oil-and-gas industry has long been the nation’s largest emitter of methane. We care about methane because climate scientists estimate that the gas is responsible for about one quarter of the global warming that has happened since industrialization.
Though no separate determination was made, there have been massive leaks from natural gas storage facilities. The most recent large release was the Aliso Canyon Natural Gas Facility leak from October 2015 through February 2016 when at least 109,000 metric tons of methane was released. The equipment was not adequately maintained, but the 2016 regulations would not have prevented that failure. Different regulations limiting the life of storage vessels are needed to address that.
At the time EPA proposed two actions:
- The agency would remove from the regulations sources of methane in the transmission and storage segment of the oil and gas industry. These sources include transmission compressor stations, pneumatic controllers, and underground storage vessels. The agency noted at the time that including these sources to the 2016 rule was not appropriate because that the agency did not make a separate finding to determine that the emissions from the transmission and storage segment of the industry causes or significantly contributes to air pollution that may endanger public health or welfare.
- The agency also would rescind emissions limits for methane, from the production and processing segments of the industry but would keep emissions limits for ozone-forming volatile organic compounds (VOCs). These sources include well completions, pneumatic pumps, pneumatic controllers, gathering and boosting compressors, natural gas processing plants and storage tanks. The controls to reduce VOCs emissions also reduce methane at the same time, so the EPA stated that separate methane limitations for that segment of the industry are redundant.
At that time EPA Administrator Andrew Wheeler said: “The Trump Administration recognizes that methane is valuable, and the industry has an incentive to minimize leaks and maximize its use. Since 1990, natural gas production in the United States has almost doubled while methane emissions across the natural gas industry have fallen by nearly 15%. Our regulations should not stifle this innovation and progress.”
According to the U.S. EPA, methane is the second most prevalent greenhouse gas and accounted for about 10% of all U.S. greenhouse gas emissions from human activities. Methane is emitted by natural sources such as wetlands and the breakdown of organic material, as well as from leakage from natural gas systems, growing rice, waste disposal and the raising of livestock. However, as you can see on the right, the oil-and-gas industry has long been the nation’s largest emitter of methane. We care about methane because climate scientists estimate that the gas is responsible for about one quarter of the global warming that has happened since industrialization.
Though no separate determination was made, there have been massive leaks from natural gas storage facilities. The most recent large release was the Aliso Canyon Natural Gas Facility leak from October 2015 through February 2016 when at least 109,000 metric tons of methane was released. The equipment was not adequately maintained, but the 2016 regulations would not have prevented that failure. Different regulations limiting the life of storage vessels are needed to address that.
The amount of methane in Earth’s atmosphere continues to rise. Concentrations of methane now exceed 1875 parts per billion, about 2.5 times as much as was in the atmosphere in the 1850s. This data is from the study liked above. The lead author of the study was R.B. (Rob) Jackson who is Stanford’s Michelle and Kevin Douglas Provostial Professor. He is also the chair of the Global Carbon Project (globalcarbonproject.org), which is working to measure and reduce greenhouse gas emissions. Dr. Jackson research projects include establishing a global network of methane tower measurements at more than 80 sites worldwide and measuring and reducing methane emissions from oil and gas wells, city streets, and homes and buildings. I sincerely hope that this regulatory change does not undermine these efforts.
Monday, August 10, 2020
Invasive Species threatens Progress in Bay Cleanup
![]() |
| New Water Chesnut species from USGS |
Once water chestnut shows up in a water body, it spreads to cover large areas chocking out all other life. If allowed to flower and reproduce, can spread far and wide carried by Canadian geese, other wild life and the flow of the rivers and streams. This plant forms dense floating mats that cover the water surface, blocking sunlight and killing aquatic grasses and vegetation. Dr. Nancy Rybicki formerly of the U.S. Geological Survey and now teaching at George Mason University has been trying to alert owners of ponds and other water bodies that have been impacted.
Across Northern Virginia, this invasive water chestnut has spread to dozens of locations. It can still be stopped before it takes hold, but we need to act soon, before the water chestnut spreads from the small ponds it has infested and spreads to the Potomac River. Last year this new species of water chestnut was confined to 12 locations in Fairfax and Prince William counties. Now , it has been sited in 54 locations in 5 counties. It is spreading quickly.
It is spreading in stormwater ponds, farm ponds, golf water hazards, and ponds in parks. Once it flowers with a pink flower it produces its 2 horned fruit with barbs that attach to wildlife, but are sharp enough to puncture a shoe. The water chestnut is an aquatic annual herb. The fruit though horned and barbed is edible and has medicinal qualities and was probably brought to Northern Virginia intentionally. It sprouts from seeds in spring and the plants die off in winter after a hard frost, but the seeds can lie dormant for several years and be washed from a spill way down river.
![]() |
| from USGS |
If this new water chestnut is allowed to establish itself in ponds around Virginia it could spread into the tidal waters, and we will face an epic control challenge that would both undo past decades of successful eradication of invasive species and undermine all our efforts under the Chesapeake Bay Total Maximum Daily Load (TMDL) and the resulting estuary water quality improvements- in restoration of the population of submersed aquatic vegetation. The Chesapeake Bay TMDL is a “pollution diet” mandated by the U.S.EPA to restore the health of the Bay and its local streams, creeks and rivers. The Chesapeake Bay TMDL—the largest such cleanup plan ever developed by the U.S. EPA—sets limits on nitrogen, phosphorus and sediment pollution necessary to meet water quality standards in the Bay and its tidal rivers.
Sparta NC Earthquake Could Impact Your Well
The August 9th, 2020 M 5.1 earthquake near Sparta, North Carolina, occurred at 8:07 am. This earthquake occurred in the interior of the North American plate. Such mid-plate earthquakes are known as intraplate earthquakes and are generally less common than interplate earthquakes that happen near tectonic plate boundaries. This earthquake was preceded by at least four small foreshocks ranging from M 2.1-2.6, beginning about 25 hours prior to the mainshock.
Large earthquakes are relatively uncommon in this region. Moderately damaging earthquakes strike the inland Carolinas every few decades, and smaller earthquakes are felt once every year or two. In the 20th century, one earthquake M5 and larger occurred within 100 km to this August 9th events, a M5.2 in the Great Smoky Mountains in 1916. The largest recent earthquake to impact the east coast was the M5.8 Mineral Virginia earthquake on August 23rd, 2011, roughly 300 km to the northeast of this August 9th earthquake. The Sparta earthquake was not as widely felt.
Private wells can be impacted by earthquakes. The most common type of observed ground-water response is an instantaneous water-level fall or rise and can occur near or far from the epicenter of the quake without significant change to the rock formation. Recovery to the pre-earthquake water level can be so rapid as to be almost unnoticeable, or it may take as long as several days or months. Water level changes can be large enough to make a well flow to the land surface, or render a well dry.
Well water can also become cloudy or take on a different color, smell and feel. The water can become contaminated with dirt, minerals and other solids, as well as bacteria due to damage to the casing and grouting. To see if your well has been impacted, you will have to empty your pressure tank and see what pumps out of the well. Turbidity could move through the system and pass in a short period or not depending on the specific geology, soil type and hydro geology. However, if there are any indications of impact the water should be tested to ensure it is still potable.
In 1998 there was an earthquake in northwestern Pennsylvania that caused about 120 local household drinking water wells to go dry within 3 months after the earthquake, they never recovered. Very large earthquakes even at great distances can also cause the water table to temporarily rise and fall when the seismic long waves pass through the state and this is the most common type of groundwater response. The USGS documented a 2-foot water-level rise in a well in Wisconsin, in 2002 after an earthquake in Alaska more than a thousand miles away.
Large earthquakes are relatively uncommon in this region. Moderately damaging earthquakes strike the inland Carolinas every few decades, and smaller earthquakes are felt once every year or two. In the 20th century, one earthquake M5 and larger occurred within 100 km to this August 9th events, a M5.2 in the Great Smoky Mountains in 1916. The largest recent earthquake to impact the east coast was the M5.8 Mineral Virginia earthquake on August 23rd, 2011, roughly 300 km to the northeast of this August 9th earthquake. The Sparta earthquake was not as widely felt.
Private wells can be impacted by earthquakes. The most common type of observed ground-water response is an instantaneous water-level fall or rise and can occur near or far from the epicenter of the quake without significant change to the rock formation. Recovery to the pre-earthquake water level can be so rapid as to be almost unnoticeable, or it may take as long as several days or months. Water level changes can be large enough to make a well flow to the land surface, or render a well dry.
Well water can also become cloudy or take on a different color, smell and feel. The water can become contaminated with dirt, minerals and other solids, as well as bacteria due to damage to the casing and grouting. To see if your well has been impacted, you will have to empty your pressure tank and see what pumps out of the well. Turbidity could move through the system and pass in a short period or not depending on the specific geology, soil type and hydro geology. However, if there are any indications of impact the water should be tested to ensure it is still potable.
In 1998 there was an earthquake in northwestern Pennsylvania that caused about 120 local household drinking water wells to go dry within 3 months after the earthquake, they never recovered. Very large earthquakes even at great distances can also cause the water table to temporarily rise and fall when the seismic long waves pass through the state and this is the most common type of groundwater response. The USGS documented a 2-foot water-level rise in a well in Wisconsin, in 2002 after an earthquake in Alaska more than a thousand miles away.
Thursday, August 6, 2020
New Study Narrows the Range Planet’s Future Temperature
![]() |
| NOAA graph. Data from NOAA and ETHZ. Our World in Data and the Global Carbon Project. |
Now, a new research paper conducted under the World Climate Reasearch Programme (WCRP) and funded in part by The Department of Energy Office of Science, Office of Biological and Environmental Research, was published two weeks ago in Reviews of Geophysics. Because of the public funding, Lawrence Livermore Laboratory makes the article available for free at this link.
The research was made possible by bringing together an international team of researchers from a wide range of climate disciplines. Using temperature records since the industrial revolution, paleoclimate records to estimate prehistoric temperatures, satellite observations and detailed models that examine the physics of interactions within the climate system, the team was able to narrow the likely temperature range to 4.7-7.0˚F. (This is equivalent to between a warming range of between 2.6°C and 3.9°C.)
Since 1800 when temperature records began, average surface temperatures have risen by almost 2 degrees Fahrenheit or 1.1 degrees Celsius. The planet has not been warming uniformly. The Pacific and Southern Oceans have acted as a heat sink for those portions of the planet. Eventually, those waters will warm and increase cloud cover above the oceans. Global CO2 emissions have continued to grow and scientists are forecasting that atmospheric CO2 concentrations will reach 560 ppm by 2060. Science Magazine published an excellent review and summary by Paul Voosen at this link.
Based on air bubbles trapped in mile-thick ice cores (and other paleoclimate evidence), scientists know that during the ice age cycles of the past million years or so, carbon dioxide never exceeded 300 ppm. Before the Industrial Revolution started in the mid-1700s, the global average amount of carbon dioxide was about 280 ppm.
By the time continuous observations began at Mauna Loa Volcanic Observatory in 1958, global atmospheric carbon dioxide was already 315 ppm. On May 9, 2013, the daily average carbon dioxide measured at Mauna Loa surpassed 400 ppm for the first time on record. Scientists once hoped that CO2 emissions could be held below the “tipping point,” now the plan is to quickly reach peak emissions and then reverse course reducing global net human-caused CO2 emissions by about 45 % from 2010 levels by 2030 and reaching ‘net zero’ emissions around 2050. (Forbes, 2019). The current strategy requires that fossil fuels are replaced by low or no-carbon technologies and we further decouple global GDP from CO2 emissions.
Monday, August 3, 2020
Our Future: Ubiquitous Plastic Waste
During my lifetime, the use of plastics has expanded exponentially. When I was young, shampoo bottles were glass, trash bags were wax coated paper, wax paper were used to wrap food and drinks from milk to soda came in glass bottles. Plastic is a wonder, but is also one of the most commonly littered items in the world.
Plastics that we use once and discard, or single-use plastics, are a growing problem of critical global proportion. Plastic is to be found littering beaches and landscapes and clogging our waste streams and landfills, the exponential growth of plastics is now threatening the survival of our planet.
Scientists studied the amount of plastics that have been manufactured since 1950’s and determined it’s fate and found that virtually all the plastic we ever made is non-degradable and is still with us. Much of the plastic ends up in landfills, or worn into smaller particles in the soil, in the ocean, or in our rivers, streams, lakes and estuaries, even in the air we breath.
The scientists estimated that more than 9,000 million metric tons of virgin plastics have been produced since the dawn of the age of plastics and found that around 9% of which had been recycled, 12% was incinerated, and 79% was accumulated in landfills or the natural environment. The amount of plastic waste keeps growing.
Plastic bottles cannot be recycled into new plastic bottles- the fibers cannot be used to make food quality plastic and have to be used for fleece, carpeting or other product. In addition, the one bin recycling which for a time was used everywhere in the U.S. became a mixed and dirty waste bin. When China adopted it National Sword policy in 2018 which essentially halted plastic and mixed waste imports that practice stopped. China once imported about half of the world’s recyclable waste. No more.
In May of last year the parties to the Basel Convention voted to amend the treaty to include waste plastic. Effective January 1, 2021 the export of import of plastic waste is prohibited by Basel parties. This will close all ports to U.S. plastic waste exports and we will have to address our problem. The Basel Convention regulates the movements around the globe of hazardous and other wastes including; toxic, poisonous, explosive, corrosive, flammable, ecologically toxic and infectious wastes. The goal of the Basel Convention is to ensure that wastes are managed and disposed of in an environmentally sound manner.
In the U.S. plastic manufacturing is regulated by the Environmental Protection Agency. However, plastic waste is mostly managed by the states under the Solid Waste Disposal Act. This is beginning to change with the U.S. EPA EPA’s the Microbead-Free Waters Act of 2015 and the EPA’s Trash Free Waters program. I have not generally, been in favor of regulations directed to change consumer behavior, but the ubiquity of plastic waste requires a coordinated action.
The most recent attempt is the Break Free From Plastic Pollution Act of 2020 which stalled out after introduction in the house. The bill makes producers of products (e.g., packaging, paper, single-use products, beverage containers, or food service products) fiscally responsible for collecting, managing, and recycling or composting the products after consumer use. In addition, the bill tries to increase the percentage of recycled content in beverage containers.
The need for some action is obvious when I’m standing in the grocery store and see shopper after shopper with carts full of single serving soda and water bottles many of the type I see again at our river cleanups. However, I do not see a way to make corporations responsible for what includes a large portion of consumer behavior. Even during the recent Covid-19 lockdown when we were all at home near the glasses we could fill with water from the sink (or our filter pitchers or refrigerator filters). Single serve, single use bottles continued to be cleared off the shelves. This is not good decision making. According to Consumer Reports (June 2020 CR.org) the U.S. our plastic recycling rates are pathetic (though better than the global averages) 76% of plastic garbage goes to landfills, 16% is incinerated, 1% is littered, and the rest recycled. This data is from a time when China was taking everything we put in the recycle bin. What we really need to do is eliminate the use of traditional plastic in many short life applications.
On solution is refillable water bottles. Another is biodegradable plastics. Chitin can be used as a substitute for plastics in food packaging or bottles and for foam products, microbeads and other application that have made plastics so ubiquitous. Found in the exoskeletons of arthropods (shrimp, crab, lobster, insects), chitin is the second most abundant organic polymer in nature, cellulose is the most abundant. The chitin and its derivative chitosan, offers many of plastic’s desirable properties and takes only weeks or months to biodegrade, rather than centuries that petroleum based polymers take to degrade.
Plastics that we use once and discard, or single-use plastics, are a growing problem of critical global proportion. Plastic is to be found littering beaches and landscapes and clogging our waste streams and landfills, the exponential growth of plastics is now threatening the survival of our planet.
Scientists studied the amount of plastics that have been manufactured since 1950’s and determined it’s fate and found that virtually all the plastic we ever made is non-degradable and is still with us. Much of the plastic ends up in landfills, or worn into smaller particles in the soil, in the ocean, or in our rivers, streams, lakes and estuaries, even in the air we breath.
The scientists estimated that more than 9,000 million metric tons of virgin plastics have been produced since the dawn of the age of plastics and found that around 9% of which had been recycled, 12% was incinerated, and 79% was accumulated in landfills or the natural environment. The amount of plastic waste keeps growing.
Plastic bottles cannot be recycled into new plastic bottles- the fibers cannot be used to make food quality plastic and have to be used for fleece, carpeting or other product. In addition, the one bin recycling which for a time was used everywhere in the U.S. became a mixed and dirty waste bin. When China adopted it National Sword policy in 2018 which essentially halted plastic and mixed waste imports that practice stopped. China once imported about half of the world’s recyclable waste. No more.
In May of last year the parties to the Basel Convention voted to amend the treaty to include waste plastic. Effective January 1, 2021 the export of import of plastic waste is prohibited by Basel parties. This will close all ports to U.S. plastic waste exports and we will have to address our problem. The Basel Convention regulates the movements around the globe of hazardous and other wastes including; toxic, poisonous, explosive, corrosive, flammable, ecologically toxic and infectious wastes. The goal of the Basel Convention is to ensure that wastes are managed and disposed of in an environmentally sound manner.
In the U.S. plastic manufacturing is regulated by the Environmental Protection Agency. However, plastic waste is mostly managed by the states under the Solid Waste Disposal Act. This is beginning to change with the U.S. EPA EPA’s the Microbead-Free Waters Act of 2015 and the EPA’s Trash Free Waters program. I have not generally, been in favor of regulations directed to change consumer behavior, but the ubiquity of plastic waste requires a coordinated action.
The most recent attempt is the Break Free From Plastic Pollution Act of 2020 which stalled out after introduction in the house. The bill makes producers of products (e.g., packaging, paper, single-use products, beverage containers, or food service products) fiscally responsible for collecting, managing, and recycling or composting the products after consumer use. In addition, the bill tries to increase the percentage of recycled content in beverage containers.
The need for some action is obvious when I’m standing in the grocery store and see shopper after shopper with carts full of single serving soda and water bottles many of the type I see again at our river cleanups. However, I do not see a way to make corporations responsible for what includes a large portion of consumer behavior. Even during the recent Covid-19 lockdown when we were all at home near the glasses we could fill with water from the sink (or our filter pitchers or refrigerator filters). Single serve, single use bottles continued to be cleared off the shelves. This is not good decision making. According to Consumer Reports (June 2020 CR.org) the U.S. our plastic recycling rates are pathetic (though better than the global averages) 76% of plastic garbage goes to landfills, 16% is incinerated, 1% is littered, and the rest recycled. This data is from a time when China was taking everything we put in the recycle bin. What we really need to do is eliminate the use of traditional plastic in many short life applications.
On solution is refillable water bottles. Another is biodegradable plastics. Chitin can be used as a substitute for plastics in food packaging or bottles and for foam products, microbeads and other application that have made plastics so ubiquitous. Found in the exoskeletons of arthropods (shrimp, crab, lobster, insects), chitin is the second most abundant organic polymer in nature, cellulose is the most abundant. The chitin and its derivative chitosan, offers many of plastic’s desirable properties and takes only weeks or months to biodegrade, rather than centuries that petroleum based polymers take to degrade.
Subscribe to:
Posts (Atom)








