rgeospatialpolygonspatialshapefile

R Convert a list of polygons into a shapefile, where each polygon is a feature of the shapefile

I'm trying to convert this list of polygons, named all_buffers, into a shapefile. I'd like each polygon to be its own feature in the shapefile. Everything I've tried has only exported one single polygon.

I'm not 100% sure what the polygons will look like, as I wrote a code to create them and need to plot them out to see if I have the correct output of polygons.

Here is one example of code that leads to a shapefile with a single polygon in the output:

# convert list to to sf object
all_buffers_df <- as.data.frame(all_buffers)
all_buffers_sf <- st_sf(all_buffers_df)

# Write the sf object to a shapefile
st_write(all_buffers_sf, output_shapefile)

Here is the output of dput(all_buffers[1:3])

list(structure(list(structure(list(structure(c(1643236.4086072, 
1643238.48985526, 1643240.90097465, 1643331.86535965, 1643332.12136799, 
1643491.9559765, 1643540.07354953, 1643541.07809514, 1643542.45620144, 
1643544.20359104, 1643546.31484036, 1643548.78339648, 1643551.60159745, 
1643841.6391826, 1643880.02768436, 1643862.74577757, 1643862.70783685, 
1643863.02018494, 1643863.68192662, 1643864.69116521, 1643866.04500806, 
1643903.30422821, 1643903.247472, 1643903.41383696, 1643903.91480187, 
1643904.74899362, 1643905.91412575, 1643907.4070047, 1643909.22353862, 
1643911.35874849, 1643913.80678186, 1643916.56092884, 1643919.61364051, 
1643922.95654959, 1643926.58049341, 1643930.47553897, 1643934.63101025, 
1643939.03551737, 1643943.67698789, 1643948.54269986, 1643953.6193167, 
1643958.89292377, 1643964.34906646, 1643969.97278987, 1643975.74867977, 
1643981.66090485, 1643987.69326009, 1643993.82921125, 1644000.0519401, 
1644006.34439058, 1644012.68931551, 1644019.0693239, 1644025.46692859, 
1644031.86459419, 1644038.24478514, 1644044.59001378, 1644050.88288829, 
1644057.10616033, 1644063.24277234, 1644069.27590429, 1644075.1890198, 
1644080.96591142, 1644086.5907451, 1644092.04810356, 1644097.32302855, 
1644102.40106187, 1644107.26828499, 1644111.91135719, 1644116.31755213, 
1644120.47479273, 1644124.37168429, 1644127.9975457, 1644131.34243872, 
1644134.39719524, 1644137.15344238, 1644139.60362545, 1644141.74102869, 
1644143.5597936, 1644145.05493509, 1644146.22235508, 1644147.05885374, 
1644147.5621383, 1644147.73082929, 1644147.79021236, 1644147.58002816, 
1644146.9475896, 1644145.89508505, 1644144.42615639, 1644107.63552073, 
1644124.73035412, 1644124.75473163, 1644124.36394607, 1644123.55932507, 
1644080.92227123, 1644079.85680313, 1644078.466711, 1644076.75575718, 
1644074.72857245, 1644072.39064348, 1644069.74829798, 1643780.32038485, 
1643732.54475991, 1643731.69910241, 1643730.5743334, 1643729.17305785, 
1643727.49852112, 1643725.55460144, 1643723.34580095, 1643556.57204004, 
1643468.31116325, 1643415.86842324, 1643413.83925947, 1643411.4952172, 
1643408.84272127, 1643405.88904199, 1643402.6422752, 1643399.11132005, 
1643395.30585465, 1643391.23630951, 1643386.91383897, 1643382.35029063, 
1643377.55817286, 1643372.55062051, 1643367.34135894, 1643361.94466637, 
1643356.37533476, 1643350.64862926, 1643344.78024638, 1643338.78627095, 
1643332.68313202, 1643326.48755789, 1643320.21653019, 1643313.88723738, 
1643307.51702759, 1643301.12336115, 1643294.72376263, 1643288.3357729, 
1643281.976901, 1643275.66457614, 1643269.41609997, 1643263.24859914, 
1643257.17897832, 1643251.22387394, 1643245.39960851, 1643239.72214595, 
1643234.20704778, 1643228.86943051, 1643223.72392417, 1643218.78463224, 
1643214.06509297, 1643209.57824229, 1643205.33637836, 1643201.35112782, 
1643197.63341396, 1643194.19342679, 1643191.04059507, 1643188.18356049, 
1643185.63015399, 1643183.38737427, 1643181.46136864, 1643179.85741614, 
1643178.5799131, 1643177.63236107, 1643177.01735721, 1643176.73658722, 
1643176.79082066, 1643177.17990888, 1643177.90278542, 1643178.95746893, 
1643180.34106858, 1643182.04979204, 1643236.4086072, 243269.326850644, 
243275.539407347, 243281.631529932, 243494.604529177, 243495.199546814, 
243863.994530239, 244262.430265543, 244269.166085889, 244275.835509451, 
244282.417835576, 244288.892633946, 244295.239807988, 244301.439657251, 
244895.030051468, 245162.946393988, 245693.383455872, 245699.92775685, 
245706.464709768, 245712.975578585, 245719.441702018, 245725.844547036, 
245881.364510288, 246193.575732921, 246199.97339852, 246206.353589471, 
246212.698818115, 246218.991692621, 246225.214964657, 246231.351576667, 
246237.384708624, 246243.297824133, 246249.074715755, 246254.699549432, 
246260.156907886, 246265.431832876, 246270.5098662, 246275.377089322, 
246280.020161521, 246284.426356458, 246288.583597061, 246292.480488621, 
246296.106350029, 246299.451243052, 246302.50599957, 246305.262246708, 
246307.712429784, 246309.849833017, 246311.668597932, 246313.163739422, 
246314.331159408, 246315.167658072, 246315.670942631, 246315.839633615, 
246315.673268656, 246315.172303746, 246314.338111998, 246313.172979871, 
246311.680100913, 246309.863567001, 246307.728357127, 246305.280323755, 
246302.526176772, 246299.473465105, 246296.130556024, 246292.506612211, 
246288.611566643, 246284.45609537, 246280.051588249, 246275.410117729, 
246270.544405758, 246265.467788913, 246260.194181849, 246254.738039157, 
246249.114315743, 246243.338425844, 246237.426200771, 246231.393845523, 
246225.257894366, 246219.035165516, 246212.74271504, 246206.397790107, 
246200.017781716, 246193.620177026, 245866.95875686, 245859.771141828, 
245852.608320546, 245845.495077866, 245838.456027088, 245684.891935232, 
245160.196754918, 245153.071697909, 245145.957323847, 245138.87780291, 
244841.310484664, 244835.04081447, 244828.835040508, 244822.709958987, 
244816.682147719, 244810.767921248, 244804.983286699, 244212.640646117, 
243817.036398995, 243811.214631001, 243805.440290011, 243799.726749426, 
243794.087241829, 243788.534828346, 243783.082368389, 243398.276305639, 
243191.632973258, 243019.945559645, 243013.87593883, 243007.920834446, 
243002.096569019, 242996.419106456, 242990.904008288, 242985.566391015, 
242980.420884675, 242975.481592744, 242970.762053477, 242966.275202803, 
242962.033338868, 242958.048088327, 242954.330374473, 242950.890387303, 
242947.737555582, 242944.880521003, 242942.327114498, 242940.084334778, 
242938.158329146, 242936.554376649, 242935.27687361, 242934.329321575, 
242933.71431772, 242933.433547727, 242933.487781166, 242933.876869388, 
242934.59974593, 242935.654429436, 242937.038029092, 242938.746752548, 
242940.775916313, 242943.119958588, 242945.772454517, 242948.726133793, 
242951.972900587, 242955.503855736, 242959.309321138, 242963.378866276, 
242967.701336811, 242972.26488515, 242977.057002926, 242982.064555276, 
242987.273816847, 242992.670509417, 242998.239841024, 243003.966546519, 
243009.8349294, 243015.828904838, 243021.932043761, 243028.127617892, 
243034.398645591, 243040.727938407, 243047.09814819, 243053.491814636, 
243059.891413151, 243066.27940288, 243072.638274786, 243078.950599645, 
243085.199075811, 243091.366576648, 243269.326850644), dim = c(172L, 
2L))), class = c("XY", "POLYGON", "sfg"))), n_empty = 0L, precision = 0, crs = structure(list(
    input = "NAD83(HARN) / Washington South (ftUS) + EGM96 height", 
    wkt = "COMPOUNDCRS[\"NAD83(HARN) / Washington South (ftUS) + EGM96 height\",\n    PROJCRS[\"NAD83(HARN) / Washington South (ftUS)\",\n        BASEGEOGCRS[\"NAD83(HARN)\",\n            DATUM[\"NAD83 (High Accuracy Reference Network)\",\n                ELLIPSOID[\"GRS 1980\",6378137,298.257222101,\n                    LENGTHUNIT[\"metre\",1]],\n                ID[\"EPSG\",6152]],\n            PRIMEM[\"Greenwich\",0,\n                ANGLEUNIT[\"Degree\",0.0174532925199433]]],\n        CONVERSION[\"unnamed\",\n            METHOD[\"Lambert Conic Conformal (2SP)\",\n                ID[\"EPSG\",9802]],\n            PARAMETER[\"Latitude of false origin\",45.3333333333333,\n                ANGLEUNIT[\"Degree\",0.0174532925199433],\n                ID[\"EPSG\",8821]],\n            PARAMETER[\"Longitude of false origin\",-120.5,\n                ANGLEUNIT[\"Degree\",0.0174532925199433],\n                ID[\"EPSG\",8822]],\n            PARAMETER[\"Latitude of 1st standard parallel\",45.8333333333333,\n                ANGLEUNIT[\"Degree\",0.0174532925199433],\n                ID[\"EPSG\",8823]],\n            PARAMETER[\"Latitude of 2nd standard parallel\",47.3333333333333,\n                ANGLEUNIT[\"Degree\",0.0174532925199433],\n                ID[\"EPSG\",8824]],\n            PARAMETER[\"Easting at false origin\",1640416.66666667,\n                LENGTHUNIT[\"US survey foot\",0.304800609601219],\n                ID[\"EPSG\",8826]],\n            PARAMETER[\"Northing at false origin\",0,\n                LENGTHUNIT[\"US survey foot\",0.304800609601219],\n                ID[\"EPSG\",8827]]],\n        CS[Cartesian,2],\n            AXIS[\"(E)\",east,\n                ORDER[1],\n                LENGTHUNIT[\"US survey foot\",0.304800609601219,\n                    ID[\"EPSG\",9003]]],\n            AXIS[\"(N)\",north,\n                ORDER[2],\n                LENGTHUNIT[\"US survey foot\",0.304800609601219,\n                    ID[\"EPSG\",9003]]]],\n    VERTCRS[\"EGM96 height\",\n        VDATUM[\"EGM96 geoid\"],\n        CS[vertical,1],\n            AXIS[\"gravity-related height (H)\",up,\n                LENGTHUNIT[\"metre\",1,\n                    ID[\"EPSG\",9001]]]]]"), class = "crs"), class = c("sfc_POLYGON", 
"sfc"), bbox = structure(c(xmin = 1643176.73658722, ymin = 242933.433547727, 
xmax = 1644147.79021236, ymax = 246315.839633615), class = "bbox")), 
    structure(list(structure(list(structure(c(1643236.4086072, 
    1643238.48985526, 1643240.90097465, 1643331.86535965, 1643332.12136799, 
    1643491.9559765, 1643540.07354953, 1643541.07809514, 1643542.45620144, 
    1643544.20359104, 1643546.31484036, 1643548.78339648, 1643551.60159745, 
    1643841.6391826, 1643880.02768436, 1643862.74577757, 1643862.70783685, 
    1643863.02018494, 1643863.68192662, 1643864.69116521, 1643866.04500806, 
    1643903.30422821, 1643903.247472, 1643903.41383696, 1643903.91480187, 
    1643904.74899362, 1643905.91412575, 1643907.4070047, 1643909.22353862, 
    1643911.35874849, 1643913.80678186, 1643916.56092884, 1643919.61364051, 
    1643922.95654959, 1643926.58049341, 1643930.47553897, 1643934.63101025, 
    1643939.03551737, 1643943.67698789, 1643948.54269986, 1643953.6193167, 
    1643958.89292377, 1643964.34906646, 1643969.97278987, 1643975.74867977, 
    1643981.66090485, 1643987.69326009, 1643993.82921125, 1644000.0519401, 
    1644006.34439058, 1644012.68931551, 1644019.0693239, 1644025.46692859, 
    1644031.86459419, 1644038.24478514, 1644044.59001378, 1644050.88288829, 
    1644057.10616033, 1644063.24277234, 1644069.27590429, 1644075.1890198, 
    1644080.96591142, 1644086.5907451, 1644092.04810356, 1644097.32302855, 
    1644102.40106187, 1644107.26828499, 1644111.91135719, 1644116.31755213, 
    1644120.47479273, 1644124.37168429, 1644127.9975457, 1644131.34243872, 
    1644134.39719524, 1644137.15344238, 1644139.60362545, 1644141.74102869, 
    1644143.5597936, 1644145.05493509, 1644146.22235508, 1644147.05885374, 
    1644147.5621383, 1644147.73082929, 1644147.79021236, 1644147.58002816, 
    1644146.9475896, 1644145.89508505, 1644144.42615639, 1644107.63552073, 
    1644124.73035412, 1644124.75473163, 1644124.36394607, 1644123.55932507, 
    1644080.92227123, 1644079.85680313, 1644078.466711, 1644076.75575718, 
    1644074.72857245, 1644072.39064348, 1644069.74829798, 1643780.32038485, 
    1643732.54475991, 1643731.69910241, 1643730.5743334, 1643729.17305785, 
    1643727.49852112, 1643725.55460144, 1643723.34580095, 1643556.57204004, 
    1643468.31116325, 1643415.86842324, 1643413.83925947, 1643411.4952172, 
    1643408.84272127, 1643405.88904199, 1643402.6422752, 1643399.11132005, 
    1643395.30585465, 1643391.23630951, 1643386.91383897, 1643382.35029063, 
    1643377.55817286, 1643372.55062051, 1643367.34135894, 1643361.94466637, 
    1643356.37533476, 1643350.64862926, 1643344.78024638, 1643338.78627095, 
    1643332.68313202, 1643326.48755789, 1643320.21653019, 1643313.88723738, 
    1643307.51702759, 1643301.12336115, 1643294.72376263, 1643288.3357729, 
    1643281.976901, 1643275.66457614, 1643269.41609997, 1643263.24859914, 
    1643257.17897832, 1643251.22387394, 1643245.39960851, 1643239.72214595, 
    1643234.20704778, 1643228.86943051, 1643223.72392417, 1643218.78463224, 
    1643214.06509297, 1643209.57824229, 1643205.33637836, 1643201.35112782, 
    1643197.63341396, 1643194.19342679, 1643191.04059507, 1643188.18356049, 
    1643185.63015399, 1643183.38737427, 1643181.46136864, 1643179.85741614, 
    1643178.5799131, 1643177.63236107, 1643177.01735721, 1643176.73658722, 
    1643176.79082066, 1643177.17990888, 1643177.90278542, 1643178.95746893, 
    1643180.34106858, 1643182.04979204, 1643236.4086072, 243269.326850644, 
    243275.539407347, 243281.631529932, 243494.604529177, 243495.199546814, 
    243863.994530239, 244262.430265543, 244269.166085889, 244275.835509451, 
    244282.417835576, 244288.892633946, 244295.239807988, 244301.439657251, 
    244895.030051468, 245162.946393988, 245693.383455872, 245699.92775685, 
    245706.464709768, 245712.975578585, 245719.441702018, 245725.844547036, 
    245881.364510288, 246193.575732921, 246199.97339852, 246206.353589471, 
    246212.698818115, 246218.991692621, 246225.214964657, 246231.351576667, 
    246237.384708624, 246243.297824133, 246249.074715755, 246254.699549432, 
    246260.156907886, 246265.431832876, 246270.5098662, 246275.377089322, 
    246280.020161521, 246284.426356458, 246288.583597061, 246292.480488621, 
    246296.106350029, 246299.451243052, 246302.50599957, 246305.262246708, 
    246307.712429784, 246309.849833017, 246311.668597932, 246313.163739422, 
    246314.331159408, 246315.167658072, 246315.670942631, 246315.839633615, 
    246315.673268656, 246315.172303746, 246314.338111998, 246313.172979871, 
    246311.680100913, 246309.863567001, 246307.728357127, 246305.280323755, 
    246302.526176772, 246299.473465105, 246296.130556024, 246292.506612211, 
    246288.611566643, 246284.45609537, 246280.051588249, 246275.410117729, 
    246270.544405758, 246265.467788913, 246260.194181849, 246254.738039157, 
    246249.114315743, 246243.338425844, 246237.426200771, 246231.393845523, 
    246225.257894366, 246219.035165516, 246212.74271504, 246206.397790107, 
    246200.017781716, 246193.620177026, 245866.95875686, 245859.771141828, 
    245852.608320546, 245845.495077866, 245838.456027088, 245684.891935232, 
    245160.196754918, 245153.071697909, 245145.957323847, 245138.87780291, 
    244841.310484664, 244835.04081447, 244828.835040508, 244822.709958987, 
    244816.682147719, 244810.767921248, 244804.983286699, 244212.640646117, 
    243817.036398995, 243811.214631001, 243805.440290011, 243799.726749426, 
    243794.087241829, 243788.534828346, 243783.082368389, 243398.276305639, 
    243191.632973258, 243019.945559645, 243013.87593883, 243007.920834446, 
    243002.096569019, 242996.419106456, 242990.904008288, 242985.566391015, 
    242980.420884675, 242975.481592744, 242970.762053477, 242966.275202803, 
    242962.033338868, 242958.048088327, 242954.330374473, 242950.890387303, 
    242947.737555582, 242944.880521003, 242942.327114498, 242940.084334778, 
    242938.158329146, 242936.554376649, 242935.27687361, 242934.329321575, 
    242933.71431772, 242933.433547727, 242933.487781166, 242933.876869388, 
    242934.59974593, 242935.654429436, 242937.038029092, 242938.746752548, 
    242940.775916313, 242943.119958588, 242945.772454517, 242948.726133793, 
    242951.972900587, 242955.503855736, 242959.309321138, 242963.378866276, 
    242967.701336811, 242972.26488515, 242977.057002926, 242982.064555276, 
    242987.273816847, 242992.670509417, 242998.239841024, 243003.966546519, 
    243009.8349294, 243015.828904838, 243021.932043761, 243028.127617892, 
    243034.398645591, 243040.727938407, 243047.09814819, 243053.491814636, 
    243059.891413151, 243066.27940288, 243072.638274786, 243078.950599645, 
    243085.199075811, 243091.366576648, 243269.326850644), dim = c(172L, 
    2L))), class = c("XY", "POLYGON", "sfg"))), n_empty = 0L, precision = 0, crs = structure(list(
        input = "NAD83(HARN) / Washington South (ftUS) + EGM96 height", 
        wkt = "COMPOUNDCRS[\"NAD83(HARN) / Washington South (ftUS) + EGM96 height\",\n    PROJCRS[\"NAD83(HARN) / Washington South (ftUS)\",\n        BASEGEOGCRS[\"NAD83(HARN)\",\n            DATUM[\"NAD83 (High Accuracy Reference Network)\",\n                ELLIPSOID[\"GRS 1980\",6378137,298.257222101,\n                    LENGTHUNIT[\"metre\",1]],\n                ID[\"EPSG\",6152]],\n            PRIMEM[\"Greenwich\",0,\n                ANGLEUNIT[\"Degree\",0.0174532925199433]]],\n        CONVERSION[\"unnamed\",\n            METHOD[\"Lambert Conic Conformal (2SP)\",\n                ID[\"EPSG\",9802]],\n            PARAMETER[\"Latitude of false origin\",45.3333333333333,\n                ANGLEUNIT[\"Degree\",0.0174532925199433],\n                ID[\"EPSG\",8821]],\n            PARAMETER[\"Longitude of false origin\",-120.5,\n                ANGLEUNIT[\"Degree\",0.0174532925199433],\n                ID[\"EPSG\",8822]],\n            PARAMETER[\"Latitude of 1st standard parallel\",45.8333333333333,\n                ANGLEUNIT[\"Degree\",0.0174532925199433],\n                ID[\"EPSG\",8823]],\n            PARAMETER[\"Latitude of 2nd standard parallel\",47.3333333333333,\n                ANGLEUNIT[\"Degree\",0.0174532925199433],\n                ID[\"EPSG\",8824]],\n            PARAMETER[\"Easting at false origin\",1640416.66666667,\n                LENGTHUNIT[\"US survey foot\",0.304800609601219],\n                ID[\"EPSG\",8826]],\n            PARAMETER[\"Northing at false origin\",0,\n                LENGTHUNIT[\"US survey foot\",0.304800609601219],\n                ID[\"EPSG\",8827]]],\n        CS[Cartesian,2],\n            AXIS[\"(E)\",east,\n                ORDER[1],\n                LENGTHUNIT[\"US survey foot\",0.304800609601219,\n                    ID[\"EPSG\",9003]]],\n            AXIS[\"(N)\",north,\n                ORDER[2],\n                LENGTHUNIT[\"US survey foot\",0.304800609601219,\n                    ID[\"EPSG\",9003]]]],\n    VERTCRS[\"EGM96 height\",\n        VDATUM[\"EGM96 geoid\"],\n        CS[vertical,1],\n            AXIS[\"gravity-related height (H)\",up,\n                LENGTHUNIT[\"metre\",1,\n                    ID[\"EPSG\",9001]]]]]"), class = "crs"), class = c("sfc_POLYGON", 
    "sfc"), bbox = structure(c(xmin = 1643176.73658722, ymin = 242933.433547727, 
    xmax = 1644147.79021236, ymax = 246315.839633615), class = "bbox")), 
    structure(list(structure(list(structure(c(1643236.4086072, 
    1643238.48985526, 1643240.90097465, 1643331.86535965, 1643332.12136799, 
    1643491.9559765, 1643540.07354953, 1643541.07809514, 1643542.45620144, 
    1643544.20359104, 1643546.31484036, 1643548.78339648, 1643551.60159745, 
    1643841.6391826, 1643880.02768436, 1643862.74577757, 1643862.70783685, 
    1643863.02018494, 1643863.68192662, 1643864.69116521, 1643866.04500806, 
    1643903.30422821, 1643903.247472, 1643903.41383696, 1643903.91480187, 
    1643904.74899362, 1643905.91412575, 1643907.4070047, 1643909.22353862, 
    1643911.35874849, 1643913.80678186, 1643916.56092884, 1643919.61364051, 
    1643922.95654959, 1643926.58049341, 1643930.47553897, 1643934.63101025, 
    1643939.03551737, 1643943.67698789, 1643948.54269986, 1643953.6193167, 
    1643958.89292377, 1643964.34906646, 1643969.97278987, 1643975.74867977, 
    1643981.66090485, 1643987.69326009, 1643993.82921125, 1644000.0519401, 
    1644006.34439058, 1644012.68931551, 1644019.0693239, 1644025.46692859, 
    1644031.86459419, 1644038.24478514, 1644044.59001378, 1644050.88288829, 
    1644057.10616033, 1644063.24277234, 1644069.27590429, 1644075.1890198, 
    1644080.96591142, 1644086.5907451, 1644092.04810356, 1644097.32302855, 
    1644102.40106187, 1644107.26828499, 1644111.91135719, 1644116.31755213, 
    1644120.47479273, 1644124.37168429, 1644127.9975457, 1644131.34243872, 
    1644134.39719524, 1644137.15344238, 1644139.60362545, 1644141.74102869, 
    1644143.5597936, 1644145.05493509, 1644146.22235508, 1644147.05885374, 
    1644147.5621383, 1644147.73082929, 1644147.79021236, 1644147.58002816, 
    1644146.9475896, 1644145.89508505, 1644144.42615639, 1644107.63552073, 
    1644124.73035412, 1644124.75473163, 1644124.36394607, 1644123.55932507, 
    1644080.92227123, 1644079.85680313, 1644078.466711, 1644076.75575718, 
    1644074.72857245, 1644072.39064348, 1644069.74829798, 1643780.32038485, 
    1643732.54475991, 1643731.69910241, 1643730.5743334, 1643729.17305785, 
    1643727.49852112, 1643725.55460144, 1643723.34580095, 1643556.57204004, 
    1643468.31116325, 1643415.86842324, 1643413.83925947, 1643411.4952172, 
    1643408.84272127, 1643405.88904199, 1643402.6422752, 1643399.11132005, 
    1643395.30585465, 1643391.23630951, 1643386.91383897, 1643382.35029063, 
    1643377.55817286, 1643372.55062051, 1643367.34135894, 1643361.94466637, 
    1643356.37533476, 1643350.64862926, 1643344.78024638, 1643338.78627095, 
    1643332.68313202, 1643326.48755789, 1643320.21653019, 1643313.88723738, 
    1643307.51702759, 1643301.12336115, 1643294.72376263, 1643288.3357729, 
    1643281.976901, 1643275.66457614, 1643269.41609997, 1643263.24859914, 
    1643257.17897832, 1643251.22387394, 1643245.39960851, 1643239.72214595, 
    1643234.20704778, 1643228.86943051, 1643223.72392417, 1643218.78463224, 
    1643214.06509297, 1643209.57824229, 1643205.33637836, 1643201.35112782, 
    1643197.63341396, 1643194.19342679, 1643191.04059507, 1643188.18356049, 
    1643185.63015399, 1643183.38737427, 1643181.46136864, 1643179.85741614, 
    1643178.5799131, 1643177.63236107, 1643177.01735721, 1643176.73658722, 
    1643176.79082066, 1643177.17990888, 1643177.90278542, 1643178.95746893, 
    1643180.34106858, 1643182.04979204, 1643236.4086072, 243269.326850644, 
    243275.539407347, 243281.631529932, 243494.604529177, 243495.199546814, 
    243863.994530239, 244262.430265543, 244269.166085889, 244275.835509451, 
    244282.417835576, 244288.892633946, 244295.239807988, 244301.439657251, 
    244895.030051468, 245162.946393988, 245693.383455872, 245699.92775685, 
    245706.464709768, 245712.975578585, 245719.441702018, 245725.844547036, 
    245881.364510288, 246193.575732921, 246199.97339852, 246206.353589471, 
    246212.698818115, 246218.991692621, 246225.214964657, 246231.351576667, 
    246237.384708624, 246243.297824133, 246249.074715755, 246254.699549432, 
    246260.156907886, 246265.431832876, 246270.5098662, 246275.377089322, 
    246280.020161521, 246284.426356458, 246288.583597061, 246292.480488621, 
    246296.106350029, 246299.451243052, 246302.50599957, 246305.262246708, 
    246307.712429784, 246309.849833017, 246311.668597932, 246313.163739422, 
    246314.331159408, 246315.167658072, 246315.670942631, 246315.839633615, 
    246315.673268656, 246315.172303746, 246314.338111998, 246313.172979871, 
    246311.680100913, 246309.863567001, 246307.728357127, 246305.280323755, 
    246302.526176772, 246299.473465105, 246296.130556024, 246292.506612211, 
    246288.611566643, 246284.45609537, 246280.051588249, 246275.410117729, 
    246270.544405758, 246265.467788913, 246260.194181849, 246254.738039157, 
    246249.114315743, 246243.338425844, 246237.426200771, 246231.393845523, 
    246225.257894366, 246219.035165516, 246212.74271504, 246206.397790107, 
    246200.017781716, 246193.620177026, 245866.95875686, 245859.771141828, 
    245852.608320546, 245845.495077866, 245838.456027088, 245684.891935232, 
    245160.196754918, 245153.071697909, 245145.957323847, 245138.87780291, 
    244841.310484664, 244835.04081447, 244828.835040508, 244822.709958987, 
    244816.682147719, 244810.767921248, 244804.983286699, 244212.640646117, 
    243817.036398995, 243811.214631001, 243805.440290011, 243799.726749426, 
    243794.087241829, 243788.534828346, 243783.082368389, 243398.276305639, 
    243191.632973258, 243019.945559645, 243013.87593883, 243007.920834446, 
    243002.096569019, 242996.419106456, 242990.904008288, 242985.566391015, 
    242980.420884675, 242975.481592744, 242970.762053477, 242966.275202803, 
    242962.033338868, 242958.048088327, 242954.330374473, 242950.890387303, 
    242947.737555582, 242944.880521003, 242942.327114498, 242940.084334778, 
    242938.158329146, 242936.554376649, 242935.27687361, 242934.329321575, 
    242933.71431772, 242933.433547727, 242933.487781166, 242933.876869388, 
    242934.59974593, 242935.654429436, 242937.038029092, 242938.746752548, 
    242940.775916313, 242943.119958588, 242945.772454517, 242948.726133793, 
    242951.972900587, 242955.503855736, 242959.309321138, 242963.378866276, 
    242967.701336811, 242972.26488515, 242977.057002926, 242982.064555276, 
    242987.273816847, 242992.670509417, 242998.239841024, 243003.966546519, 
    243009.8349294, 243015.828904838, 243021.932043761, 243028.127617892, 
    243034.398645591, 243040.727938407, 243047.09814819, 243053.491814636, 
    243059.891413151, 243066.27940288, 243072.638274786, 243078.950599645, 
    243085.199075811, 243091.366576648, 243269.326850644), dim = c(172L, 
    2L))), class = c("XY", "POLYGON", "sfg"))), n_empty = 0L, precision = 0, crs = structure(list(
        input = "NAD83(HARN) / Washington South (ftUS) + EGM96 height", 
        wkt = "COMPOUNDCRS[\"NAD83(HARN) / Washington South (ftUS) + EGM96 height\",\n    PROJCRS[\"NAD83(HARN) / Washington South (ftUS)\",\n        BASEGEOGCRS[\"NAD83(HARN)\",\n            DATUM[\"NAD83 (High Accuracy Reference Network)\",\n                ELLIPSOID[\"GRS 1980\",6378137,298.257222101,\n                    LENGTHUNIT[\"metre\",1]],\n                ID[\"EPSG\",6152]],\n            PRIMEM[\"Greenwich\",0,\n                ANGLEUNIT[\"Degree\",0.0174532925199433]]],\n        CONVERSION[\"unnamed\",\n            METHOD[\"Lambert Conic Conformal (2SP)\",\n                ID[\"EPSG\",9802]],\n            PARAMETER[\"Latitude of false origin\",45.3333333333333,\n                ANGLEUNIT[\"Degree\",0.0174532925199433],\n                ID[\"EPSG\",8821]],\n            PARAMETER[\"Longitude of false origin\",-120.5,\n                ANGLEUNIT[\"Degree\",0.0174532925199433],\n                ID[\"EPSG\",8822]],\n            PARAMETER[\"Latitude of 1st standard parallel\",45.8333333333333,\n                ANGLEUNIT[\"Degree\",0.0174532925199433],\n                ID[\"EPSG\",8823]],\n            PARAMETER[\"Latitude of 2nd standard parallel\",47.3333333333333,\n                ANGLEUNIT[\"Degree\",0.0174532925199433],\n                ID[\"EPSG\",8824]],\n            PARAMETER[\"Easting at false origin\",1640416.66666667,\n                LENGTHUNIT[\"US survey foot\",0.304800609601219],\n                ID[\"EPSG\",8826]],\n            PARAMETER[\"Northing at false origin\",0,\n                LENGTHUNIT[\"US survey foot\",0.304800609601219],\n                ID[\"EPSG\",8827]]],\n        CS[Cartesian,2],\n            AXIS[\"(E)\",east,\n                ORDER[1],\n                LENGTHUNIT[\"US survey foot\",0.304800609601219,\n                    ID[\"EPSG\",9003]]],\n            AXIS[\"(N)\",north,\n                ORDER[2],\n                LENGTHUNIT[\"US survey foot\",0.304800609601219,\n                    ID[\"EPSG\",9003]]]],\n    VERTCRS[\"EGM96 height\",\n        VDATUM[\"EGM96 geoid\"],\n        CS[vertical,1],\n            AXIS[\"gravity-related height (H)\",up,\n                LENGTHUNIT[\"metre\",1,\n                    ID[\"EPSG\",9001]]]]]"), class = "crs"), class = c("sfc_POLYGON", 
    "sfc"), bbox = structure(c(xmin = 1643176.73658722, ymin = 242933.433547727, 
    xmax = 1644147.79021236, ymax = 246315.839633615), class = "bbox")))
Solution

  • You can combine sfc objects into a single sfc with c(), as you have a whole list of those, you could do do.call(what = c, all_buffers).

    I don't know how you verified that (all?) your exports include just a single polygon, but it usually helps if you plot as you go. For example in this case you are dealing with a list of identical polygons that depending on how/what you were looking for, might appear as one. By visualizing early and more often you'd probably spot such anomalies soon after they sneak in.

    library(sf)
#> Linking to GEOS 3.13.1, GDAL 3.10.2, PROJ 9.5.1; sf_use_s2() is TRUE

# all_buffers <- list(structure( ... ))
# check buffers, identical bboxes and coordinates look suspicious ... 
str(all_buffers)
#> List of 3
#>  $ :sfc_POLYGON of length 1; first list element: List of 1
#>   ..$ : num [1:172, 1:2] 1643236 1643238 1643241 1643332 1643332 ...
#>   ..- attr(*, "class")= chr [1:3] "XY" "POLYGON" "sfg"
#>  $ :sfc_POLYGON of length 1; first list element: List of 1
#>   ..$ : num [1:172, 1:2] 1643236 1643238 1643241 1643332 1643332 ...
#>   ..- attr(*, "class")= chr [1:3] "XY" "POLYGON" "sfg"
#>  $ :sfc_POLYGON of length 1; first list element: List of 1
#>   ..$ : num [1:172, 1:2] 1643236 1643238 1643241 1643332 1643332 ...
#>   ..- attr(*, "class")= chr [1:3] "XY" "POLYGON" "sfg"

# combine list into a single sfc
( all_buffers_sfc <- do.call(what = c, all_buffers) )
#> Geometry set for 3 features 
#> Geometry type: POLYGON
#> Dimension:     XY
#> Bounding box:  xmin: 1643177 ymin: 242933.4 xmax: 1644148 ymax: 246315.8
#> Projected CRS: NAD83(HARN) / Washington South (ftUS) + EGM96 height
#> POLYGON ((1643236 243269.3, 1643238 243275.5, 1...
#> POLYGON ((1643236 243269.3, 1643238 243275.5, 1...
#> POLYGON ((1643236 243269.3, 1643238 243275.5, 1...

# visualize, looks like a set of identical overlapping polygons
mapview::mapview(st_sf(all_buffers_sfc))

    mapview screenshot

    # check if all polygons are indeed identical
st_equals_exact(all_buffers_sfc, par = 0, sparse = FALSE)
#>      [,1] [,2] [,3]
#> [1,] TRUE TRUE TRUE
#> [2,] TRUE TRUE TRUE
#> [3,] TRUE TRUE TRUE

# write as GeoPackage
st_write(all_buffers_sfc, "all_buffers.gpkg")
#> Writing layer `all_buffers' to data source `all_buffers.gpkg' using driver `GPKG'
#> Writing 3 features with 0 fields and geometry type Polygon.
fs::file_info("all_buffers.gpkg")[,1:5]
#> # A tibble: 1 × 5
#>   path             type         size permissions modification_time  
#>   <fs::path>       <fct> <fs::bytes> <fs::perms> <dttm>             
#> 1 all_buffers.gpkg file         108K rw-         2025-05-02 10:32:03